| | r"""Utilities to compile possibly incomplete Python source code. |
| | |
| | This module provides two interfaces, broadly similar to the builtin |
| | function compile(), which take program text, a filename and a 'mode' |
| | and: |
| | |
| | - Return code object if the command is complete and valid |
| | - Return None if the command is incomplete |
| | - Raise SyntaxError, ValueError or OverflowError if the command is a |
| | syntax error (OverflowError and ValueError can be produced by |
| | malformed literals). |
| | |
| | The two interfaces are: |
| | |
| | compile_command(source, filename, symbol): |
| | |
| | Compiles a single command in the manner described above. |
| | |
| | CommandCompiler(): |
| | |
| | Instances of this class have __call__ methods identical in |
| | signature to compile_command; the difference is that if the |
| | instance compiles program text containing a __future__ statement, |
| | the instance 'remembers' and compiles all subsequent program texts |
| | with the statement in force. |
| | |
| | The module also provides another class: |
| | |
| | Compile(): |
| | |
| | Instances of this class act like the built-in function compile, |
| | but with 'memory' in the sense described above. |
| | """ |
| |
|
| | import __future__ |
| | import warnings |
| |
|
| | _features = [getattr(__future__, fname) |
| | for fname in __future__.all_feature_names] |
| |
|
| | __all__ = ["compile_command", "Compile", "CommandCompiler"] |
| |
|
| | |
| | |
| | |
| | PyCF_DONT_IMPLY_DEDENT = 0x200 |
| | PyCF_ALLOW_INCOMPLETE_INPUT = 0x4000 |
| |
|
| | def _maybe_compile(compiler, source, filename, symbol): |
| | |
| | for line in source.split("\n"): |
| | line = line.strip() |
| | if line and line[0] != '#': |
| | break |
| | else: |
| | if symbol != "eval": |
| | source = "pass" |
| |
|
| | |
| | with warnings.catch_warnings(): |
| | warnings.simplefilter("ignore", (SyntaxWarning, DeprecationWarning)) |
| | try: |
| | compiler(source, filename, symbol) |
| | except SyntaxError: |
| | try: |
| | compiler(source + "\n", filename, symbol) |
| | return None |
| | except SyntaxError as e: |
| | if "incomplete input" in str(e): |
| | return None |
| | |
| |
|
| | return compiler(source, filename, symbol) |
| |
|
| |
|
| | def _is_syntax_error(err1, err2): |
| | rep1 = repr(err1) |
| | rep2 = repr(err2) |
| | if "was never closed" in rep1 and "was never closed" in rep2: |
| | return False |
| | if rep1 == rep2: |
| | return True |
| | return False |
| |
|
| | def _compile(source, filename, symbol): |
| | return compile(source, filename, symbol, PyCF_DONT_IMPLY_DEDENT | PyCF_ALLOW_INCOMPLETE_INPUT) |
| |
|
| | def compile_command(source, filename="<input>", symbol="single"): |
| | r"""Compile a command and determine whether it is incomplete. |
| | |
| | Arguments: |
| | |
| | source -- the source string; may contain \n characters |
| | filename -- optional filename from which source was read; default |
| | "<input>" |
| | symbol -- optional grammar start symbol; "single" (default), "exec" |
| | or "eval" |
| | |
| | Return value / exceptions raised: |
| | |
| | - Return a code object if the command is complete and valid |
| | - Return None if the command is incomplete |
| | - Raise SyntaxError, ValueError or OverflowError if the command is a |
| | syntax error (OverflowError and ValueError can be produced by |
| | malformed literals). |
| | """ |
| | return _maybe_compile(_compile, source, filename, symbol) |
| |
|
| | class Compile: |
| | """Instances of this class behave much like the built-in compile |
| | function, but if one is used to compile text containing a future |
| | statement, it "remembers" and compiles all subsequent program texts |
| | with the statement in force.""" |
| | def __init__(self): |
| | self.flags = PyCF_DONT_IMPLY_DEDENT | PyCF_ALLOW_INCOMPLETE_INPUT |
| |
|
| | def __call__(self, source, filename, symbol): |
| | codeob = compile(source, filename, symbol, self.flags, True) |
| | for feature in _features: |
| | if codeob.co_flags & feature.compiler_flag: |
| | self.flags |= feature.compiler_flag |
| | return codeob |
| |
|
| | class CommandCompiler: |
| | """Instances of this class have __call__ methods identical in |
| | signature to compile_command; the difference is that if the |
| | instance compiles program text containing a __future__ statement, |
| | the instance 'remembers' and compiles all subsequent program texts |
| | with the statement in force.""" |
| |
|
| | def __init__(self,): |
| | self.compiler = Compile() |
| |
|
| | def __call__(self, source, filename="<input>", symbol="single"): |
| | r"""Compile a command and determine whether it is incomplete. |
| | |
| | Arguments: |
| | |
| | source -- the source string; may contain \n characters |
| | filename -- optional filename from which source was read; |
| | default "<input>" |
| | symbol -- optional grammar start symbol; "single" (default) or |
| | "eval" |
| | |
| | Return value / exceptions raised: |
| | |
| | - Return a code object if the command is complete and valid |
| | - Return None if the command is incomplete |
| | - Raise SyntaxError, ValueError or OverflowError if the command is a |
| | syntax error (OverflowError and ValueError can be produced by |
| | malformed literals). |
| | """ |
| | return _maybe_compile(self.compiler, source, filename, symbol) |
| |
|