fname stringlengths 63 176 | rel_fname stringclasses 706
values | line int64 -1 4.5k | name stringlengths 1 81 | kind stringclasses 2
values | category stringclasses 2
values | info stringlengths 0 77.9k ⌀ |
|---|---|---|---|---|---|---|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 995 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 996 | _metaclass_name | ref | class | |
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 999 | visit_assignattr | def | function | def visit_assignattr(self, node: nodes.AssignAttr) -> None:
if isinstance(node.assign_type(), nodes.AugAssign):
self.visit_attribute(node)
def visit_delattr(self, node: nodes.DelAttr) -> None:
self.visit_attribute(node)
@check_messages("no-member", "c-extension-no-member")
def visit_attribute(self, node: nodes.Attribute) -> None:
"""Check that the accessed attribute exists.
to avoid too much false positives for now, we'll consider the code as
correct if a single of the inferred nodes has the accessed attribute.
function/method, super call and metaclasses are ignored
"""
if any(
pattern.match(name)
for name in (node.attrname, node.as_string())
for pattern in self._compiled_generated_members
):
return
try:
inferred = list(node.expr.infer())
except astroid.InferenceError:
return
# list of (node, nodename) which are missing the attribute
missingattr = set()
non_opaque_inference_results = [
owner
for owner in inferred
if owner is not astroid.Uninferable and not isinstance(owner, nodes.Unknown)
]
if (
len(non_opaque_inference_results) != len(inferred)
and self.config.ignore_on_opaque_inference
):
# There is an ambiguity in the inference. Since we can't
# make sure that we won't emit a false positive, we just stop
# whenever the inference returns an opaque inference object.
return
for owner in non_opaque_inference_results:
name = getattr(owner, "name", None)
if _is_owner_ignored(
owner, name, self.config.ignored_classes, self.config.ignored_modules
):
continue
qualname = f"{owner.pytype()}.{node.attrname}"
if any(
pattern.match(qualname) for pattern in self._compiled_generated_members
):
return
try:
if not [
n
for n in owner.getattr(node.attrname)
if not isinstance(n.statement(future=_True), nodes.AugAssign)
]:
missingattr.add((owner, name))
continue
except astroid.exceptions.StatementMissing:
continue
except AttributeError:
continue
except astroid.DuplicateBasesError:
continue
except astroid.NotFoundError:
# This can't be moved before the actual .getattr call,
# because there can be more values inferred and we are
# stopping after the first one which has the attribute in question.
# The problem is that if the first one has the attribute,
# but we continue to the next values which doesn't have the
# attribute, then we'll have a false positive.
# So call this only after the call has been made.
if not _emit_no_member(
node,
owner,
name,
self._mixin_class_rgx,
ignored_mixins=self.config.ignore_mixin_members,
ignored_none=self.config.ignore_none,
):
continue
missingattr.add((owner, name))
continue
# stop on the first found
break
else:
# we have not found any node with the attributes, display the
# message for inferred nodes
done = set()
for owner, name in missingattr:
if isinstance(owner, astroid.Instance):
actual = owner._proxied
else:
actual = owner
if actual in done:
continue
done.add(actual)
msg, hint = self._get_nomember_msgid_hint(node, owner)
self.add_message(
msg,
node=node,
args=(owner.display_type(), name, node.attrname, hint),
confidence=INFERENCE,
)
def _get_nomember_msgid_hint(self, node, owner):
suggestions_are_possible = self._suggestion_mode and isinstance(
owner, nodes.Module
)
if suggestions_are_possible and _is_c_extension(owner):
msg = "c-extension-no-member"
hint = ""
else:
msg = "no-member"
if self.config.missing_member_hint:
hint = _missing_member_hint(
owner,
node.attrname,
self.config.missing_member_hint_distance,
self.config.missing_member_max_choices,
)
else:
hint = ""
return msg, hint
@check_messages(
"assignment-from-no-return",
"assignment-from-none",
"non-str-assignment-to-dunder-name",
)
def visit_assign(self, node: nodes.Assign) -> None:
"""Process assignments in the AST."""
self._check_assignment_from_function_call(node)
self._check_dundername_is_string(node)
def _check_assignment_from_function_call(self, node: nodes.Assign) -> None:
"""When assigning to a function call, check that the function returns a valid value."""
if not isinstance(node.value, nodes.Call):
return
function_node = safe_infer(node.value.func)
funcs = (nodes.FunctionDef, astroid.UnboundMethod, astroid.BoundMethod)
if not isinstance(function_node, funcs):
return
# Unwrap to get the actual function node object
if isinstance(function_node, astroid.BoundMethod) and isinstance(
function_node._proxied, astroid.UnboundMethod
):
function_node = function_node._proxied._proxied
# Make sure that it's a valid function that we can analyze.
# Ordered from less expensive to more expensive checks.
if (
not function_node.is_function
or function_node.decorators
or self._is_ignored_function(function_node)
):
return
# Fix a false-negative for list.sort(), see issue #5722
if self._is_list_sort_method(node.value):
self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
return
if not function_node.root().fully_defined():
return
return_nodes = list(
function_node.nodes_of_class(nodes.Return, skip_klass=nodes.FunctionDef)
)
if not return_nodes:
self.add_message("assignment-from-no-return", node=node)
else:
for ret_node in return_nodes:
if not (
isinstance(ret_node.value, nodes.Const)
and ret_node.value.value is None
or ret_node.value is None
):
break
else:
self.add_message("assignment-from-none", node=node)
@staticmethod
def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,000 | assign_type | ref | function | if isinstance(node.assign_type(), nodes.AugAssign):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,001 | visit_attribute | ref | function | self.visit_attribute(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,003 | visit_delattr | def | function | def visit_delattr(self, node: nodes.DelAttr) -> None:
self.visit_attribute(node)
@check_messages("no-member", "c-extension-no-member")
def visit_attribute(self, node: nodes.Attribute) -> None:
"""Check that the accessed attribute exists.
to avoid too much false positives for now, we'll consider the code as
correct if a single of the inferred nodes has the accessed attribute.
function/method, super call and metaclasses are ignored
"""
if any(
pattern.match(name)
for name in (node.attrname, node.as_string())
for pattern in self._compiled_generated_members
):
return
try:
inferred = list(node.expr.infer())
except astroid.InferenceError:
return
# list of (node, nodename) which are missing the attribute
missingattr = set()
non_opaque_inference_results = [
owner
for owner in inferred
if owner is not astroid.Uninferable and not isinstance(owner, nodes.Unknown)
]
if (
len(non_opaque_inference_results) != len(inferred)
and self.config.ignore_on_opaque_inference
):
# There is an ambiguity in the inference. Since we can't
# make sure that we won't emit a false positive, we just stop
# whenever the inference returns an opaque inference object.
return
for owner in non_opaque_inference_results:
name = getattr(owner, "name", None)
if _is_owner_ignored(
owner, name, self.config.ignored_classes, self.config.ignored_modules
):
continue
qualname = f"{owner.pytype()}.{node.attrname}"
if any(
pattern.match(qualname) for pattern in self._compiled_generated_members
):
return
try:
if not [
n
for n in owner.getattr(node.attrname)
if not isinstance(n.statement(future=_True), nodes.AugAssign)
]:
missingattr.add((owner, name))
continue
except astroid.exceptions.StatementMissing:
continue
except AttributeError:
continue
except astroid.DuplicateBasesError:
continue
except astroid.NotFoundError:
# This can't be moved before the actual .getattr call,
# because there can be more values inferred and we are
# stopping after the first one which has the attribute in question.
# The problem is that if the first one has the attribute,
# but we continue to the next values which doesn't have the
# attribute, then we'll have a false positive.
# So call this only after the call has been made.
if not _emit_no_member(
node,
owner,
name,
self._mixin_class_rgx,
ignored_mixins=self.config.ignore_mixin_members,
ignored_none=self.config.ignore_none,
):
continue
missingattr.add((owner, name))
continue
# stop on the first found
break
else:
# we have not found any node with the attributes, display the
# message for inferred nodes
done = set()
for owner, name in missingattr:
if isinstance(owner, astroid.Instance):
actual = owner._proxied
else:
actual = owner
if actual in done:
continue
done.add(actual)
msg, hint = self._get_nomember_msgid_hint(node, owner)
self.add_message(
msg,
node=node,
args=(owner.display_type(), name, node.attrname, hint),
confidence=INFERENCE,
)
def _get_nomember_msgid_hint(self, node, owner):
suggestions_are_possible = self._suggestion_mode and isinstance(
owner, nodes.Module
)
if suggestions_are_possible and _is_c_extension(owner):
msg = "c-extension-no-member"
hint = ""
else:
msg = "no-member"
if self.config.missing_member_hint:
hint = _missing_member_hint(
owner,
node.attrname,
self.config.missing_member_hint_distance,
self.config.missing_member_max_choices,
)
else:
hint = ""
return msg, hint
@check_messages(
"assignment-from-no-return",
"assignment-from-none",
"non-str-assignment-to-dunder-name",
)
def visit_assign(self, node: nodes.Assign) -> None:
"""Process assignments in the AST."""
self._check_assignment_from_function_call(node)
self._check_dundername_is_string(node)
def _check_assignment_from_function_call(self, node: nodes.Assign) -> None:
"""When assigning to a function call, check that the function returns a valid value."""
if not isinstance(node.value, nodes.Call):
return
function_node = safe_infer(node.value.func)
funcs = (nodes.FunctionDef, astroid.UnboundMethod, astroid.BoundMethod)
if not isinstance(function_node, funcs):
return
# Unwrap to get the actual function node object
if isinstance(function_node, astroid.BoundMethod) and isinstance(
function_node._proxied, astroid.UnboundMethod
):
function_node = function_node._proxied._proxied
# Make sure that it's a valid function that we can analyze.
# Ordered from less expensive to more expensive checks.
if (
not function_node.is_function
or function_node.decorators
or self._is_ignored_function(function_node)
):
return
# Fix a false-negative for list.sort(), see issue #5722
if self._is_list_sort_method(node.value):
self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
return
if not function_node.root().fully_defined():
return
return_nodes = list(
function_node.nodes_of_class(nodes.Return, skip_klass=nodes.FunctionDef)
)
if not return_nodes:
self.add_message("assignment-from-no-return", node=node)
else:
for ret_node in return_nodes:
if not (
isinstance(ret_node.value, nodes.Const)
and ret_node.value.value is None
or ret_node.value is None
):
break
else:
self.add_message("assignment-from-none", node=node)
@staticmethod
def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,004 | visit_attribute | ref | function | self.visit_attribute(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,006 | check_messages | ref | function | @check_messages("no-member", "c-extension-no-member")
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,007 | visit_attribute | def | function | def visit_attribute(self, node: nodes.Attribute) -> None:
"""Check that the accessed attribute exists.
to avoid too much false positives for now, we'll consider the code as
correct if a single of the inferred nodes has the accessed attribute.
function/method, super call and metaclasses are ignored
"""
if any(
pattern.match(name)
for name in (node.attrname, node.as_string())
for pattern in self._compiled_generated_members
):
return
try:
inferred = list(node.expr.infer())
except astroid.InferenceError:
return
# list of (node, nodename) which are missing the attribute
missingattr = set()
non_opaque_inference_results = [
owner
for owner in inferred
if owner is not astroid.Uninferable and not isinstance(owner, nodes.Unknown)
]
if (
len(non_opaque_inference_results) != len(inferred)
and self.config.ignore_on_opaque_inference
):
# There is an ambiguity in the inference. Since we can't
# make sure that we won't emit a false positive, we just stop
# whenever the inference returns an opaque inference object.
return
for owner in non_opaque_inference_results:
name = getattr(owner, "name", None)
if _is_owner_ignored(
owner, name, self.config.ignored_classes, self.config.ignored_modules
):
continue
qualname = f"{owner.pytype()}.{node.attrname}"
if any(
pattern.match(qualname) for pattern in self._compiled_generated_members
):
return
try:
if not [
n
for n in owner.getattr(node.attrname)
if not isinstance(n.statement(future=_True), nodes.AugAssign)
]:
missingattr.add((owner, name))
continue
except astroid.exceptions.StatementMissing:
continue
except AttributeError:
continue
except astroid.DuplicateBasesError:
continue
except astroid.NotFoundError:
# This can't be moved before the actual .getattr call,
# because there can be more values inferred and we are
# stopping after the first one which has the attribute in question.
# The problem is that if the first one has the attribute,
# but we continue to the next values which doesn't have the
# attribute, then we'll have a false positive.
# So call this only after the call has been made.
if not _emit_no_member(
node,
owner,
name,
self._mixin_class_rgx,
ignored_mixins=self.config.ignore_mixin_members,
ignored_none=self.config.ignore_none,
):
continue
missingattr.add((owner, name))
continue
# stop on the first found
break
else:
# we have not found any node with the attributes, display the
# message for inferred nodes
done = set()
for owner, name in missingattr:
if isinstance(owner, astroid.Instance):
actual = owner._proxied
else:
actual = owner
if actual in done:
continue
done.add(actual)
msg, hint = self._get_nomember_msgid_hint(node, owner)
self.add_message(
msg,
node=node,
args=(owner.display_type(), name, node.attrname, hint),
confidence=INFERENCE,
)
def _get_nomember_msgid_hint(self, node, owner):
suggestions_are_possible = self._suggestion_mode and isinstance(
owner, nodes.Module
)
if suggestions_are_possible and _is_c_extension(owner):
msg = "c-extension-no-member"
hint = ""
else:
msg = "no-member"
if self.config.missing_member_hint:
hint = _missing_member_hint(
owner,
node.attrname,
self.config.missing_member_hint_distance,
self.config.missing_member_max_choices,
)
else:
hint = ""
return msg, hint
@check_messages(
"assignment-from-no-return",
"assignment-from-none",
"non-str-assignment-to-dunder-name",
)
def visit_assign(self, node: nodes.Assign) -> None:
"""Process assignments in the AST."""
self._check_assignment_from_function_call(node)
self._check_dundername_is_string(node)
def _check_assignment_from_function_call(self, node: nodes.Assign) -> None:
"""When assigning to a function call, check that the function returns a valid value."""
if not isinstance(node.value, nodes.Call):
return
function_node = safe_infer(node.value.func)
funcs = (nodes.FunctionDef, astroid.UnboundMethod, astroid.BoundMethod)
if not isinstance(function_node, funcs):
return
# Unwrap to get the actual function node object
if isinstance(function_node, astroid.BoundMethod) and isinstance(
function_node._proxied, astroid.UnboundMethod
):
function_node = function_node._proxied._proxied
# Make sure that it's a valid function that we can analyze.
# Ordered from less expensive to more expensive checks.
if (
not function_node.is_function
or function_node.decorators
or self._is_ignored_function(function_node)
):
return
# Fix a false-negative for list.sort(), see issue #5722
if self._is_list_sort_method(node.value):
self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
return
if not function_node.root().fully_defined():
return
return_nodes = list(
function_node.nodes_of_class(nodes.Return, skip_klass=nodes.FunctionDef)
)
if not return_nodes:
self.add_message("assignment-from-no-return", node=node)
else:
for ret_node in return_nodes:
if not (
isinstance(ret_node.value, nodes.Const)
and ret_node.value.value is None
or ret_node.value is None
):
break
else:
self.add_message("assignment-from-none", node=node)
@staticmethod
def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,017 | as_string | ref | function | for name in (node.attrname, node.as_string())
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,023 | infer | ref | function | inferred = list(node.expr.infer())
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,045 | _is_owner_ignored | ref | function | if _is_owner_ignored(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,050 | pytype | ref | function | qualname = f"{owner.pytype()}.{node.attrname}"
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,060 | statement | ref | function | if not isinstance(n.statement(future=True), nodes.AugAssign)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,078 | _emit_no_member | ref | function | if not _emit_no_member(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,104 | _get_nomember_msgid_hint | ref | function | msg, hint = self._get_nomember_msgid_hint(node, owner)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,105 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,108 | display_type | ref | function | args=(owner.display_type(), name, node.attrname, hint),
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,112 | _get_nomember_msgid_hint | def | function | def _get_nomember_msgid_hint(self, node, owner):
suggestions_are_possible = self._suggestion_mode and isinstance(
owner, nodes.Module
)
if suggestions_are_possible and _is_c_extension(owner):
msg = "c-extension-no-member"
hint = ""
else:
msg = "no-member"
if self.config.missing_member_hint:
hint = _missing_member_hint(
owner,
node.attrname,
self.config.missing_member_hint_distance,
self.config.missing_member_max_choices,
)
else:
hint = ""
return msg, hint
@check_messages(
"assignment-from-no-return",
"assignment-from-none",
"non-str-assignment-to-dunder-name",
)
def visit_assign(self, node: nodes.Assign) -> None:
"""Process assignments in the AST."""
self._check_assignment_from_function_call(node)
self._check_dundername_is_string(node)
def _check_assignment_from_function_call(self, node: nodes.Assign) -> None:
"""When assigning to a function call, check that the function returns a valid value."""
if not isinstance(node.value, nodes.Call):
return
function_node = safe_infer(node.value.func)
funcs = (nodes.FunctionDef, astroid.UnboundMethod, astroid.BoundMethod)
if not isinstance(function_node, funcs):
return
# Unwrap to get the actual function node object
if isinstance(function_node, astroid.BoundMethod) and isinstance(
function_node._proxied, astroid.UnboundMethod
):
function_node = function_node._proxied._proxied
# Make sure that it's a valid function that we can analyze.
# Ordered from less expensive to more expensive checks.
if (
not function_node.is_function
or function_node.decorators
or self._is_ignored_function(function_node)
):
return
# Fix a false-negative for list.sort(), see issue #5722
if self._is_list_sort_method(node.value):
self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
return
if not function_node.root().fully_defined():
return
return_nodes = list(
function_node.nodes_of_class(nodes.Return, skip_klass=nodes.FunctionDef)
)
if not return_nodes:
self.add_message("assignment-from-no-return", node=node)
else:
for ret_node in return_nodes:
if not (
isinstance(ret_node.value, nodes.Const)
and ret_node.value.value is None
or ret_node.value is None
):
break
else:
self.add_message("assignment-from-none", node=node)
@staticmethod
def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,116 | _is_c_extension | ref | function | if suggestions_are_possible and _is_c_extension(owner):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,122 | _missing_member_hint | ref | function | hint = _missing_member_hint(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,132 | check_messages | ref | function | @check_messages(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,137 | visit_assign | def | function | def visit_assign(self, node: nodes.Assign) -> None:
"""Process assignments in the AST."""
self._check_assignment_from_function_call(node)
self._check_dundername_is_string(node)
def _check_assignment_from_function_call(self, node: nodes.Assign) -> None:
"""When assigning to a function call, check that the function returns a valid value."""
if not isinstance(node.value, nodes.Call):
return
function_node = safe_infer(node.value.func)
funcs = (nodes.FunctionDef, astroid.UnboundMethod, astroid.BoundMethod)
if not isinstance(function_node, funcs):
return
# Unwrap to get the actual function node object
if isinstance(function_node, astroid.BoundMethod) and isinstance(
function_node._proxied, astroid.UnboundMethod
):
function_node = function_node._proxied._proxied
# Make sure that it's a valid function that we can analyze.
# Ordered from less expensive to more expensive checks.
if (
not function_node.is_function
or function_node.decorators
or self._is_ignored_function(function_node)
):
return
# Fix a false-negative for list.sort(), see issue #5722
if self._is_list_sort_method(node.value):
self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
return
if not function_node.root().fully_defined():
return
return_nodes = list(
function_node.nodes_of_class(nodes.Return, skip_klass=nodes.FunctionDef)
)
if not return_nodes:
self.add_message("assignment-from-no-return", node=node)
else:
for ret_node in return_nodes:
if not (
isinstance(ret_node.value, nodes.Const)
and ret_node.value.value is None
or ret_node.value is None
):
break
else:
self.add_message("assignment-from-none", node=node)
@staticmethod
def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,140 | _check_assignment_from_function_call | ref | function | self._check_assignment_from_function_call(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,141 | _check_dundername_is_string | ref | function | self._check_dundername_is_string(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,143 | _check_assignment_from_function_call | def | function | def _check_assignment_from_function_call(self, node: nodes.Assign) -> None:
"""When assigning to a function call, check that the function returns a valid value."""
if not isinstance(node.value, nodes.Call):
return
function_node = safe_infer(node.value.func)
funcs = (nodes.FunctionDef, astroid.UnboundMethod, astroid.BoundMethod)
if not isinstance(function_node, funcs):
return
# Unwrap to get the actual function node object
if isinstance(function_node, astroid.BoundMethod) and isinstance(
function_node._proxied, astroid.UnboundMethod
):
function_node = function_node._proxied._proxied
# Make sure that it's a valid function that we can analyze.
# Ordered from less expensive to more expensive checks.
if (
not function_node.is_function
or function_node.decorators
or self._is_ignored_function(function_node)
):
return
# Fix a false-negative for list.sort(), see issue #5722
if self._is_list_sort_method(node.value):
self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
return
if not function_node.root().fully_defined():
return
return_nodes = list(
function_node.nodes_of_class(nodes.Return, skip_klass=nodes.FunctionDef)
)
if not return_nodes:
self.add_message("assignment-from-no-return", node=node)
else:
for ret_node in return_nodes:
if not (
isinstance(ret_node.value, nodes.Const)
and ret_node.value.value is None
or ret_node.value is None
):
break
else:
self.add_message("assignment-from-none", node=node)
@staticmethod
def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,148 | safe_infer | ref | function | function_node = safe_infer(node.value.func)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,164 | _is_ignored_function | ref | function | or self._is_ignored_function(function_node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,169 | _is_list_sort_method | ref | function | if self._is_list_sort_method(node.value):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,170 | add_message | ref | function | self.add_message("assignment-from-none", node=node, confidence=INFERENCE)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,173 | root | ref | function | if not function_node.root().fully_defined():
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,173 | fully_defined | ref | function | if not function_node.root().fully_defined():
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,177 | nodes_of_class | ref | class | |
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,180 | add_message | ref | function | self.add_message("assignment-from-no-return", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,190 | add_message | ref | function | self.add_message("assignment-from-none", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,193 | _is_ignored_function | def | function | def _is_ignored_function(
function_node: Union[nodes.FunctionDef, bases.UnboundMethod]
) -> bool:
return (
isinstance(function_node, nodes.AsyncFunctionDef)
or utils.is_error(function_node)
or function_node.is_generator()
or function_node.is_abstract(pass_is_abstract=_False)
)
@staticmethod
def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,198 | is_error | ref | function | or utils.is_error(function_node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,199 | is_generator | ref | function | or function_node.is_generator()
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,200 | is_abstract | ref | function | or function_node.is_abstract(pass_is_abstract=False)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,204 | _is_list_sort_method | def | function | def _is_list_sort_method(node: nodes.Call) -> bool:
return (
isinstance(node.func, nodes.Attribute)
and node.func.attrname == "sort"
and isinstance(utils.safe_infer(node.func.expr), nodes.List)
)
def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,208 | safe_infer | ref | function | and isinstance(utils.safe_infer(node.func.expr), nodes.List)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,211 | _check_dundername_is_string | def | function | def _check_dundername_is_string(self, node) -> None:
"""Check a string is assigned to self.__name__."""
# Check the left-hand side of the assignment is <something>.__name__
lhs = node.targets[0]
if not isinstance(lhs, nodes.AssignAttr):
return
if not lhs.attrname == "__name__":
return
# If the right-hand side is not a string
rhs = node.value
if isinstance(rhs, nodes.Const) and isinstance(rhs.value, str):
return
inferred = utils.safe_infer(rhs)
if not inferred:
return
if not (isinstance(inferred, nodes.Const) and isinstance(inferred.value, str)):
# Add the message
self.add_message("non-str-assignment-to-dunder-name", node=node)
def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,225 | safe_infer | ref | function | inferred = utils.safe_infer(rhs)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,230 | add_message | ref | function | self.add_message("non-str-assignment-to-dunder-name", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,232 | _check_uninferable_call | def | function | def _check_uninferable_call(self, node):
"""Check that the given uninferable Call node does not
call an actual function.
"""
if not isinstance(node.func, nodes.Attribute):
return
# Look for properties. First, obtain
# the lhs of the Attribute node and search the attribute
# there. If that attribute is a property or a subclass of properties,
# then most likely it's not callable.
expr = node.func.expr
klass = safe_infer(expr)
if (
klass is None
or klass is astroid.Uninferable
or not isinstance(klass, astroid.Instance)
):
return
try:
attrs = klass._proxied.getattr(node.func.attrname)
except astroid.NotFoundError:
return
for attr in attrs:
if attr is astroid.Uninferable:
continue
if not isinstance(attr, nodes.FunctionDef):
continue
# Decorated, see if it is decorated with a property.
# Also, check the returns and see if they are callable.
if decorated_with_property(attr):
try:
all_returns_are_callable = all(
return_node.callable() or return_node is astroid.Uninferable
for return_node in attr.infer_call_result(node)
)
except astroid.InferenceError:
continue
if not all_returns_are_callable:
self.add_message(
"not-callable", node=node, args=node.func.as_string()
)
break
def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,245 | safe_infer | ref | function | klass = safe_infer(expr)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,266 | decorated_with_property | ref | function | if decorated_with_property(attr):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,271 | infer_call_result | ref | function | for return_node in attr.infer_call_result(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,277 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,278 | as_string | ref | function | "not-callable", node=node, args=node.func.as_string()
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,282 | _check_argument_order | def | function | def _check_argument_order(self, node, call_site, called, called_param_names):
"""Match the supplied argument names against the function parameters.
Warn if some argument names are not in the same order as they are in
the function signature.
"""
# Check for called function being an object instance function
# If so, ignore the initial 'self' argument in the signature
try:
is_classdef = isinstance(called.parent, nodes.ClassDef)
if is_classdef and called_param_names[0] == "self":
called_param_names = called_param_names[1:]
except IndexError:
return
try:
# extract argument names, if they have names
calling_parg_names = [p.name for p in call_site.positional_arguments]
# Additionally, get names of keyword arguments to use in a full match
# against parameters
calling_kwarg_names = [
arg.name for arg in call_site.keyword_arguments.values()
]
except AttributeError:
# the type of arg does not provide a `.name`. In this case we
# stop checking for out-of-order arguments because it is only relevant
# for named variables.
return
# Don't check for ordering if there is an unmatched arg or param
arg_set = set(calling_parg_names) | set(calling_kwarg_names)
param_set = set(called_param_names)
if arg_set != param_set:
return
# Warn based on the equality of argument ordering
if calling_parg_names != called_param_names[: len(calling_parg_names)]:
self.add_message("arguments-out-of-order", node=node, args=())
def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,319 | add_message | ref | function | self.add_message("arguments-out-of-order", node=node, args=())
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,321 | _check_isinstance_args | def | function | def _check_isinstance_args(self, node):
if len(node.args) != 2:
# isinstance called with wrong number of args
return
second_arg = node.args[1]
if _is_invalid_isinstance_type(second_arg):
self.add_message("isinstance-second-argument-not-valid-type", node=node)
# pylint: disable=too-many-branches,too-many-locals
@check_messages(*(list(MSGS.keys())))
def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,327 | _is_invalid_isinstance_type | ref | function | if _is_invalid_isinstance_type(second_arg):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,328 | add_message | ref | function | self.add_message("isinstance-second-argument-not-valid-type", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,331 | check_messages | ref | function | @check_messages(*(list(MSGS.keys())))
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,332 | visit_call | def | function | def visit_call(self, node: nodes.Call) -> None:
"""Check that called functions/methods are inferred to callable objects,
and that the arguments passed to the function match the parameters in
the inferred function's definition
"""
called = safe_infer(node.func)
self._check_not_callable(node, called)
try:
called, implicit_args, callable_name = _determine_callable(called)
except ValueError:
# Any error occurred during determining the function type, most of
# those errors are handled by different warnings.
return
if called.args.args is None:
if called.name == "isinstance":
# Verify whether second argument of isinstance is a valid type
self._check_isinstance_args(node)
# Built-in functions have no argument information.
return
if len(called.argnames()) != len(set(called.argnames())):
# Duplicate parameter name (see duplicate-argument). We can't really
# make sense of the function call in this case, so just return.
return
# Build the set of keyword arguments, checking for duplicate keywords,
# and count the positional arguments.
call_site = astroid.arguments.CallSite.from_call(node)
# Warn about duplicated keyword arguments, such as `f=24, **{'f': 24}`
for keyword in call_site.duplicated_keywords:
self.add_message("repeated-keyword", node=node, args=(keyword,))
if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
# Can't make sense of this.
return
# Has the function signature changed in ways we cannot reliably detect?
if hasattr(called, "decorators") and decorated_with(
called, self.config.signature_mutators
):
return
num_positional_args = len(call_site.positional_arguments)
keyword_args = list(call_site.keyword_arguments.keys())
overload_function = is_overload_stub(called)
# Determine if we don't have a context for our call and we use variadics.
node_scope = node.scope()
if isinstance(node_scope, (nodes.Lambda, nodes.FunctionDef)):
has_no_context_positional_variadic = _no_context_variadic_positional(
node, node_scope
)
has_no_context_keywords_variadic = _no_context_variadic_keywords(
node, node_scope
)
else:
has_no_context_positional_variadic = (
has_no_context_keywords_variadic
) = _False
# These are coming from the functools.partial implementation in astroid
already_filled_positionals = getattr(called, "filled_positionals", 0)
already_filled_keywords = getattr(called, "filled_keywords", {})
keyword_args += list(already_filled_keywords)
num_positional_args += implicit_args + already_filled_positionals
# Analyze the list of formal parameters.
args = list(itertools.chain(called.args.posonlyargs or (), called.args.args))
num_mandatory_parameters = len(args) - len(called.args.defaults)
parameters: List[List[Any]] = []
parameter_name_to_index = {}
for i, arg in enumerate(args):
if isinstance(arg, nodes.Tuple):
name = None
# Don't store any parameter names within the tuple, since those
# are not assignable from keyword arguments.
else:
assert isinstance(arg, nodes.AssignName)
# This occurs with:
# def f( (a), (b) ): pass
name = arg.name
parameter_name_to_index[name] = i
if i >= num_mandatory_parameters:
defval = called.args.defaults[i - num_mandatory_parameters]
else:
defval = None
parameters.append([(name, defval), _False])
kwparams = {}
for i, arg in enumerate(called.args.kwonlyargs):
if isinstance(arg, nodes.Keyword):
name = arg.arg
else:
assert isinstance(arg, nodes.AssignName)
name = arg.name
kwparams[name] = [called.args.kw_defaults[i], _False]
self._check_argument_order(
node, call_site, called, [p[0][0] for p in parameters]
)
# 1. Match the positional arguments.
for i in range(num_positional_args):
if i < len(parameters):
parameters[i][1] = _True
elif called.args.vararg is not None:
# The remaining positional arguments get assigned to the *args
# parameter.
break
elif not overload_function:
# Too many positional arguments.
self.add_message(
"too-many-function-args", node=node, args=(callable_name,)
)
break
# 2. Match the keyword arguments.
for keyword in keyword_args:
if keyword in parameter_name_to_index:
i = parameter_name_to_index[keyword]
if parameters[i][1]:
# Duplicate definition of function parameter.
# Might be too hardcoded, but this can actually
# happen when using str.format and `self` is passed
# by keyword argument, as in `.format(self=self)`.
# It's perfectly valid to so, so we're just skipping
# it if that's the case.
if not (keyword == "self" and called.qname() in STR_FORMAT):
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
parameters[i][1] = _True
elif keyword in kwparams:
if kwparams[keyword][1]:
# Duplicate definition of function parameter.
self.add_message(
"redundant-keyword-arg",
node=node,
args=(keyword, callable_name),
)
else:
kwparams[keyword][1] = _True
elif called.args.kwarg is not None:
# The keyword argument gets assigned to the **kwargs parameter.
pass
elif isinstance(
called, nodes.FunctionDef
) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
pass
elif not overload_function:
# Unexpected keyword argument.
self.add_message(
"unexpected-keyword-arg", node=node, args=(keyword, callable_name)
)
# 3. Match the **kwargs, if any.
if node.kwargs:
for i, [(name, defval), assigned] in enumerate(parameters):
# Assume that *kwargs provides values for all remaining
# unassigned named parameters.
if name is not None:
parameters[i][1] = _True
else:
# **kwargs can't assign to tuples.
pass
# Check that any parameters without a default have been assigned
# values.
for [(name, defval), assigned] in parameters:
if (defval is None) and not assigned:
display_name = "<tuple>" if name is None else repr(name)
if not has_no_context_positional_variadic and not overload_function:
self.add_message(
"no-value-for-parameter",
node=node,
args=(display_name, callable_name),
)
for name, val in kwparams.items():
defval, assigned = val
if (
defval is None
and not assigned
and not has_no_context_keywords_variadic
and not overload_function
):
self.add_message("missing-kwoa", node=node, args=(name, callable_name))
@staticmethod
def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,337 | safe_infer | ref | function | called = safe_infer(node.func)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,339 | _check_not_callable | ref | function | self._check_not_callable(node, called)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,342 | _determine_callable | ref | function | called, implicit_args, callable_name = _determine_callable(called)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,351 | _check_isinstance_args | ref | function | self._check_isinstance_args(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,355 | argnames | ref | function | if len(called.argnames()) != len(set(called.argnames())):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,355 | argnames | ref | function | if len(called.argnames()) != len(set(called.argnames())):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,362 | from_call | ref | function | call_site = astroid.arguments.CallSite.from_call(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,366 | add_message | ref | function | self.add_message("repeated-keyword", node=node, args=(keyword,))
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,368 | has_invalid_arguments | ref | function | if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,368 | has_invalid_keywords | ref | function | if call_site.has_invalid_arguments() or call_site.has_invalid_keywords():
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,373 | decorated_with | ref | function | if hasattr(called, "decorators") and decorated_with(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,380 | is_overload_stub | ref | function | overload_function = is_overload_stub(called)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,383 | scope | ref | function | node_scope = node.scope()
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,385 | _no_context_variadic_positional | ref | function | has_no_context_positional_variadic = _no_context_variadic_positional(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,388 | _no_context_variadic_keywords | ref | function | has_no_context_keywords_variadic = _no_context_variadic_keywords(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,434 | _check_argument_order | ref | function | self._check_argument_order(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,448 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,465 | qname | ref | function | if not (keyword == "self" and called.qname() in STR_FORMAT):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,466 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,476 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,488 | _keyword_argument_is_in_all_decorator_returns | ref | function | ) and self._keyword_argument_is_in_all_decorator_returns(called, keyword):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,492 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,513 | add_message | ref | function | self.add_message(
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,527 | add_message | ref | function | self.add_message("missing-kwoa", node=node, args=(name, callable_name))
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,530 | _keyword_argument_is_in_all_decorator_returns | def | function | def _keyword_argument_is_in_all_decorator_returns(
func: nodes.FunctionDef, keyword: str
) -> bool:
"""Check if the keyword argument exists in all signatures of the
return values of all decorators of the function.
"""
if not func.decorators:
return _False
for decorator in func.decorators.nodes:
inferred = safe_infer(decorator)
# If we can't infer the decorator we assume it satisfies consumes
# the keyword, so we don't raise false positives
if not inferred:
return _True
# We only check arguments of function decorators
if not isinstance(inferred, nodes.FunctionDef):
return _False
for return_value in inferred.infer_call_result():
# infer_call_result() returns nodes.Const.None for None return values
# so this also catches non-returning decorators
if not isinstance(return_value, nodes.FunctionDef):
return _False
# If the return value uses a kwarg the keyword will be consumed
if return_value.args.kwarg:
continue
# Check if the keyword is another type of argument
if return_value.args.is_argument(keyword):
continue
return _False
return _True
def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,540 | safe_infer | ref | function | inferred = safe_infer(decorator)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,551 | infer_call_result | ref | function | for return_value in inferred.infer_call_result():
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,562 | is_argument | ref | function | if return_value.args.is_argument(keyword):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,569 | _check_invalid_sequence_index | def | function | def _check_invalid_sequence_index(self, subscript: nodes.Subscript):
# Look for index operations where the parent is a sequence type.
# If the types can be determined, only allow indices to be int,
# slice or instances with __index__.
parent_type = safe_infer(subscript.value)
if not isinstance(
parent_type, (nodes.ClassDef, astroid.Instance)
) or not has_known_bases(parent_type):
return None
# Determine what method on the parent this index will use
# The parent of this node will be a Subscript, and the parent of that
# node determines if the Subscript is a get, set, or delete operation.
if subscript.ctx is astroid.Store:
methodname = "__setitem__"
elif subscript.ctx is astroid.Del:
methodname = "__delitem__"
else:
methodname = "__getitem__"
# Check if this instance's __getitem__, __setitem__, or __delitem__, as
# appropriate to the statement, is implemented in a builtin sequence
# type. This way we catch subclasses of sequence types but skip classes
# that override __getitem__ and which may allow non-integer indices.
try:
methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
if methods is astroid.Uninferable:
return None
itemmethod = methods[0]
except (
astroid.AttributeInferenceError,
IndexError,
):
return None
if (
not isinstance(itemmethod, nodes.FunctionDef)
or itemmethod.root().name != "builtins"
or not itemmethod.parent
or itemmethod.parent.frame().name not in SEQUENCE_TYPES
):
return None
# For ExtSlice objects coming from visit_extslice, no further
# inference is necessary, since if we got this far the ExtSlice
# is an error.
if isinstance(subscript.value, nodes.ExtSlice):
index_type = subscript.value
else:
index_type = safe_infer(subscript.slice)
if index_type is None or index_type is astroid.Uninferable:
return None
# Constants must be of type int
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, int):
return None
# Instance values must be int, slice, or have an __index__ method
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.slice"}:
return None
try:
index_type.getattr("__index__")
return None
except astroid.NotFoundError:
pass
elif isinstance(index_type, nodes.Slice):
# A slice can be present
# here after inferring the index node, which could
# be a `slice(...)` call for instance.
return self._check_invalid_slice_index(index_type)
# Anything else is an error
self.add_message("invalid-sequence-index", node=subscript)
return None
def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,573 | safe_infer | ref | function | parent_type = safe_infer(subscript.value)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,576 | has_known_bases | ref | function | ) or not has_known_bases(parent_type):
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,594 | lookup | ref | function | methods = astroid.interpreter.dunder_lookup.lookup(parent_type, methodname)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,605 | root | ref | function | or itemmethod.root().name != "builtins"
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,607 | frame | ref | function | or itemmethod.parent.frame().name not in SEQUENCE_TYPES
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,617 | safe_infer | ref | function | index_type = safe_infer(subscript.slice)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,626 | pytype | ref | function | if index_type.pytype() in {"builtins.int", "builtins.slice"}:
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,637 | _check_invalid_slice_index | ref | function | return self._check_invalid_slice_index(index_type)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,640 | add_message | ref | function | self.add_message("invalid-sequence-index", node=subscript)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,643 | _check_not_callable | def | function | def _check_not_callable(
self, node: nodes.Call, inferred_call: Optional[nodes.NodeNG]
) -> None:
"""Checks to see if the not-callable message should be emitted.
Only functions, generators and objects defining __call__ are "callable"
We ignore instances of descriptors since astroid cannot properly handle them yet
"""
# Handle uninferable calls
if not inferred_call or inferred_call.callable():
self._check_uninferable_call(node)
return
if not isinstance(inferred_call, astroid.Instance):
self.add_message("not-callable", node=node, args=node.func.as_string())
return
# Don't emit if we can't make sure this object is callable.
if not has_known_bases(inferred_call):
return
if inferred_call.parent and isinstance(inferred_call.scope(), nodes.ClassDef):
# Ignore descriptor instances
if "__get__" in inferred_call.locals:
return
# NamedTuple instances are callable
if inferred_call.qname() == "typing.NamedTuple":
return
self.add_message("not-callable", node=node, args=node.func.as_string())
@check_messages("invalid-sequence-index")
def visit_extslice(self, node: nodes.ExtSlice) -> None:
if not node.parent or not hasattr(node.parent, "value"):
return None
# Check extended slice objects as if they were used as a sequence
# index to check if the object being sliced can support them
return self._check_invalid_sequence_index(node.parent)
def _check_invalid_slice_index(self, node: nodes.Slice) -> None:
# Check the type of each part of the slice
invalid_slices_nodes: List[nodes.NodeNG] = []
for index in (node.lower, node.upper, node.step):
if index is None:
continue
index_type = safe_infer(index)
if index_type is None or index_type is astroid.Uninferable:
continue
# Constants must be of type int or None
if isinstance(index_type, nodes.Const):
if isinstance(index_type.value, (int, type(None))):
continue
# Instance values must be of type int, None or an object
# with __index__
elif isinstance(index_type, astroid.Instance):
if index_type.pytype() in {"builtins.int", "builtins.NoneType"}:
continue
try:
index_type.getattr("__index__")
return
except astroid.NotFoundError:
pass
invalid_slices_nodes.append(index)
if not invalid_slices_nodes:
return
# Anything else is an error, unless the object that is indexed
# is a custom object, which knows how to handle this kind of slices
parent = node.parent
if isinstance(parent, nodes.ExtSlice):
parent = parent.parent
if isinstance(parent, nodes.Subscript):
inferred = safe_infer(parent.value)
if inferred is None or inferred is astroid.Uninferable:
# Don't know what this is
return
known_objects = (
nodes.List,
nodes.Dict,
nodes.Tuple,
astroid.objects.FrozenSet,
nodes.Set,
)
if not isinstance(inferred, known_objects):
# Might be an instance that knows how to handle this slice object
return
for snode in invalid_slices_nodes:
self.add_message("invalid-slice-index", node=snode)
@check_messages("not-context-manager")
def visit_with(self, node: nodes.With) -> None:
for ctx_mgr, _ in node.items:
context = astroid.context.InferenceContext()
inferred = safe_infer(ctx_mgr, context=context)
if inferred is None or inferred is astroid.Uninferable:
continue
if isinstance(inferred, astroid.bases.Generator):
# Check if we are dealing with a function decorated
# with contextlib.contextmanager.
if decorated_with(
inferred.parent, self.config.contextmanager_decorators
):
continue
# If the parent of the generator is not the context manager itself,
# that means that it could have been returned from another
# function which was the real context manager.
# The following approach is more of a hack rather than a real
# solution: walk all the inferred statements for the
# given *ctx_mgr* and if you find one function scope
# which is decorated, consider it to be the real
# manager and give up, otherwise emit not-context-manager.
# See the test file for not_context_manager for a couple
# of self explaining tests.
# Retrieve node from all previously visited nodes in the
# inference history
context_path_names: Iterator[Any] = filter(
None, _unflatten(context.path)
)
inferred_paths = _flatten_container(
safe_infer(path) for path in context_path_names
)
for inferred_path in inferred_paths:
if not inferred_path:
continue
scope = inferred_path.scope()
if not isinstance(scope, nodes.FunctionDef):
continue
if decorated_with(scope, self.config.contextmanager_decorators):
break
else:
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
else:
try:
inferred.getattr("__enter__")
inferred.getattr("__exit__")
except astroid.NotFoundError:
if isinstance(inferred, astroid.Instance):
# If we do not know the bases of this class,
# just skip it.
if not has_known_bases(inferred):
continue
# Just ignore mixin classes.
if self.config.ignore_mixin_members:
if inferred.name[-5:].lower() == "mixin":
continue
self.add_message(
"not-context-manager", node=node, args=(inferred.name,)
)
@check_messages("invalid-unary-operand-type")
def visit_unaryop(self, node: nodes.UnaryOp) -> None:
"""Detect TypeErrors for unary operands."""
for error in node.type_errors():
# Let the error customize its output.
self.add_message("invalid-unary-operand-type", args=str(error), node=node)
@check_messages("unsupported-binary-operation")
def visit_binop(self, node: nodes.BinOp) -> None:
if node.op == "|":
self._detect_unsupported_alternative_union_syntax(node)
def _detect_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Detect if unsupported alternative Union syntax (PEP 604) was used."""
if self._py310_plus: # 310+ supports the new syntax
return
if isinstance(
node.parent, TYPE_ANNOTATION_NODES_TYPES
) and not is_postponed_evaluation_enabled(node):
# Use in type annotations only allowed if
# postponed evaluation is enabled.
self._check_unsupported_alternative_union_syntax(node)
if isinstance(
node.parent,
(
nodes.Assign,
nodes.Call,
nodes.Keyword,
nodes.Dict,
nodes.Tuple,
nodes.Set,
nodes.List,
nodes.BinOp,
),
):
# Check other contexts the syntax might appear, but are invalid.
# Make sure to filter context if postponed evaluation is enabled
# and parent is allowed node type.
allowed_nested_syntax = _False
if is_postponed_evaluation_enabled(node):
parent_node = node.parent
while _True:
if isinstance(parent_node, TYPE_ANNOTATION_NODES_TYPES):
allowed_nested_syntax = _True
break
parent_node = parent_node.parent
if isinstance(parent_node, nodes.Module):
break
if not allowed_nested_syntax:
self._check_unsupported_alternative_union_syntax(node)
def _check_unsupported_alternative_union_syntax(self, node: nodes.BinOp) -> None:
"""Check if left or right node is of type `type`."""
msg = "unsupported operand type(s) for |"
for n in (node.left, node.right):
n = astroid.helpers.object_type(n)
if isinstance(n, nodes.ClassDef) and is_classdef_type(n):
self.add_message("unsupported-binary-operation", args=msg, node=node)
break
@check_messages("unsupported-binary-operation")
def _visit_binop(self, node: nodes.BinOp) -> None:
"""Detect TypeErrors for binary arithmetic operands."""
self._check_binop_errors(node)
@check_messages("unsupported-binary-operation")
def _visit_augassign(self, node: nodes.AugAssign) -> None:
"""Detect TypeErrors for augmented binary arithmetic operands."""
self._check_binop_errors(node)
def _check_binop_errors(self, node):
for error in node.type_errors():
# Let the error customize its output.
if any(
isinstance(obj, nodes.ClassDef) and not has_known_bases(obj)
for obj in (error.left_type, error.right_type)
):
continue
self.add_message("unsupported-binary-operation", args=str(error), node=node)
def _check_membership_test(self, node):
if is_inside_abstract_class(node):
return
if is_comprehension(node):
return
inferred = safe_infer(node)
if inferred is None or inferred is astroid.Uninferable:
return
if not supports_membership_test(inferred):
self.add_message(
"unsupported-membership-test", args=node.as_string(), node=node
)
@check_messages("unsupported-membership-test")
def visit_compare(self, node: nodes.Compare) -> None:
if len(node.ops) != 1:
return
op, right = node.ops[0]
if op in {"in", "not in"}:
self._check_membership_test(right)
@check_messages(
"unsubscriptable-object",
"unsupported-assignment-operation",
"unsupported-delete-operation",
"unhashable-dict-key",
"invalid-sequence-index",
"invalid-slice-index",
)
def visit_subscript(self, node: nodes.Subscript) -> None:
self._check_invalid_sequence_index(node)
supported_protocol: Optional[Callable[[Any, Any], bool]] = None
if isinstance(node.value, (nodes.ListComp, nodes.DictComp)):
return
if isinstance(node.value, nodes.Dict):
# Assert dict key is hashable
inferred = safe_infer(node.slice)
if inferred and inferred != astroid.Uninferable:
try:
hash_fn = next(inferred.igetattr("__hash__"))
except astroid.InferenceError:
pass
else:
if getattr(hash_fn, "value", _True) is None:
self.add_message("unhashable-dict-key", node=node.value)
if node.ctx == astroid.Load:
supported_protocol = supports_getitem
msg = "unsubscriptable-object"
elif node.ctx == astroid.Store:
supported_protocol = supports_setitem
msg = "unsupported-assignment-operation"
elif node.ctx == astroid.Del:
supported_protocol = supports_delitem
msg = "unsupported-delete-operation"
if isinstance(node.value, nodes.SetComp):
self.add_message(msg, args=node.value.as_string(), node=node.value)
return
if is_inside_abstract_class(node):
return
inferred = safe_infer(node.value)
if inferred is None or inferred is astroid.Uninferable:
return
if getattr(inferred, "decorators", None):
first_decorator = astroid.helpers.safe_infer(inferred.decorators.nodes[0])
if isinstance(first_decorator, nodes.ClassDef):
inferred = first_decorator.instantiate_class()
else:
return # It would be better to handle function
# decorators, but let's start slow.
if supported_protocol and not supported_protocol(inferred, node):
self.add_message(msg, args=node.value.as_string(), node=node.value)
@check_messages("dict-items-missing-iter")
def visit_for(self, node: nodes.For) -> None:
if not isinstance(node.target, nodes.Tuple):
# target is not a tuple
return
if not len(node.target.elts) == 2:
# target is not a tuple of two elements
return
iterable = node.iter
if not isinstance(iterable, nodes.Name):
# it's not a bare variable
return
inferred = safe_infer(iterable)
if not inferred:
return
if not isinstance(inferred, nodes.Dict):
# the iterable is not a dict
return
if all(isinstance(i[0], nodes.Tuple) for i in inferred.items):
# if all keys are tuples
return
self.add_message("dict-iter-missing-items", node=node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,653 | _check_uninferable_call | ref | function | self._check_uninferable_call(node)
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,657 | add_message | ref | function | self.add_message("not-callable", node=node, args=node.func.as_string())
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,657 | as_string | ref | function | self.add_message("not-callable", node=node, args=node.func.as_string())
|
playground/e9b22a58-260b-483f-88d7-7a5fe9f8b1d4/pylint/pylint/checkers/typecheck.py | pylint/checkers/typecheck.py | 1,661 | has_known_bases | ref | function | if not has_known_bases(inferred_call):
|
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