Upload backend/venv/lib/python3.10/site-packages/jsonpatch.py with huggingface_hub

backend/venv/lib/python3.10/site-packages/jsonpatch.py

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+# -*- coding: utf-8 -*-
+#
+# python-json-patch - An implementation of the JSON Patch format
+# https://github.com/stefankoegl/python-json-patch
+#
+# Copyright (c) 2011 Stefan Kögl <stefan@skoegl.net>
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+# 3. The name of the author may not be used to endorse or promote products
+#    derived from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+
+""" Apply JSON-Patches (RFC 6902) """
+
+from __future__ import unicode_literals
+
+import collections
+import copy
+import functools
+import json
+import sys
+
+try:
+    from collections.abc import Sequence
+except ImportError:  # Python 3
+    from collections import Sequence
+
+try:
+    from types import MappingProxyType
+except ImportError:
+    # Python < 3.3
+    MappingProxyType = dict
+
+from jsonpointer import JsonPointer, JsonPointerException
+
+
+_ST_ADD = 0
+_ST_REMOVE = 1
+
+
+try:
+    from collections.abc import MutableMapping, MutableSequence
+
+except ImportError:
+    from collections import MutableMapping, MutableSequence
+    str = unicode
+
+# Will be parsed by setup.py to determine package metadata
+__author__ = 'Stefan Kögl <stefan@skoegl.net>'
+__version__ = '1.33'
+__website__ = 'https://github.com/stefankoegl/python-json-patch'
+__license__ = 'Modified BSD License'
+
+
+# pylint: disable=E0611,W0404
+if sys.version_info >= (3, 0):
+    basestring = (bytes, str)  # pylint: disable=C0103,W0622
+
+
+class JsonPatchException(Exception):
+    """Base Json Patch exception"""
+
+
+class InvalidJsonPatch(JsonPatchException):
+    """ Raised if an invalid JSON Patch is created """
+
+
+class JsonPatchConflict(JsonPatchException):
+    """Raised if patch could not be applied due to conflict situation such as:
+    - attempt to add object key when it already exists;
+    - attempt to operate with nonexistence object key;
+    - attempt to insert value to array at position beyond its size;
+    - etc.
+    """
+
+
+class JsonPatchTestFailed(JsonPatchException, AssertionError):
+    """ A Test operation failed """
+
+
+def multidict(ordered_pairs):
+    """Convert duplicate keys values to lists."""
+    # read all values into lists
+    mdict = collections.defaultdict(list)
+    for key, value in ordered_pairs:
+        mdict[key].append(value)
+
+    return dict(
+        # unpack lists that have only 1 item
+        (key, values[0] if len(values) == 1 else values)
+        for key, values in mdict.items()
+    )
+
+
+# The "object_pairs_hook" parameter is used to handle duplicate keys when
+# loading a JSON object.
+_jsonloads = functools.partial(json.loads, object_pairs_hook=multidict)
+
+
+def apply_patch(doc, patch, in_place=False, pointer_cls=JsonPointer):
+    """Apply list of patches to specified json document.
+
+    :param doc: Document object.
+    :type doc: dict
+
+    :param patch: JSON patch as list of dicts or raw JSON-encoded string.
+    :type patch: list or str
+
+    :param in_place: While :const:`True` patch will modify target document.
+                     By default patch will be applied to document copy.
+    :type in_place: bool
+
+    :param pointer_cls: JSON pointer class to use.
+    :type pointer_cls: Type[JsonPointer]
+
+    :return: Patched document object.
+    :rtype: dict
+
+    >>> doc = {'foo': 'bar'}
+    >>> patch = [{'op': 'add', 'path': '/baz', 'value': 'qux'}]
+    >>> other = apply_patch(doc, patch)
+    >>> doc is not other
+    True
+    >>> other == {'foo': 'bar', 'baz': 'qux'}
+    True
+    >>> patch = [{'op': 'add', 'path': '/baz', 'value': 'qux'}]
+    >>> apply_patch(doc, patch, in_place=True) == {'foo': 'bar', 'baz': 'qux'}
+    True
+    >>> doc == other
+    True
+    """
+
+    if isinstance(patch, basestring):
+        patch = JsonPatch.from_string(patch, pointer_cls=pointer_cls)
+    else:
+        patch = JsonPatch(patch, pointer_cls=pointer_cls)
+    return patch.apply(doc, in_place)
+
+
+def make_patch(src, dst, pointer_cls=JsonPointer):
+    """Generates patch by comparing two document objects. Actually is
+    a proxy to :meth:`JsonPatch.from_diff` method.
+
+    :param src: Data source document object.
+    :type src: dict
+
+    :param dst: Data source document object.
+    :type dst: dict
+
+    :param pointer_cls: JSON pointer class to use.
+    :type pointer_cls: Type[JsonPointer]
+
+    >>> src = {'foo': 'bar', 'numbers': [1, 3, 4, 8]}
+    >>> dst = {'baz': 'qux', 'numbers': [1, 4, 7]}
+    >>> patch = make_patch(src, dst)
+    >>> new = patch.apply(src)
+    >>> new == dst
+    True
+    """
+
+    return JsonPatch.from_diff(src, dst, pointer_cls=pointer_cls)
+
+
+class PatchOperation(object):
+    """A single operation inside a JSON Patch."""
+
+    def __init__(self, operation, pointer_cls=JsonPointer):
+        self.pointer_cls = pointer_cls
+
+        if not operation.__contains__('path'):
+            raise InvalidJsonPatch("Operation must have a 'path' member")
+
+        if isinstance(operation['path'], self.pointer_cls):
+            self.location = operation['path'].path
+            self.pointer = operation['path']
+        else:
+            self.location = operation['path']
+            try:
+                self.pointer = self.pointer_cls(self.location)
+            except TypeError as ex:
+                raise InvalidJsonPatch("Invalid 'path'")
+
+        self.operation = operation
+
+    def apply(self, obj):
+        """Abstract method that applies a patch operation to the specified object."""
+        raise NotImplementedError('should implement the patch operation.')
+
+    def __hash__(self):
+        return hash(frozenset(self.operation.items()))
+
+    def __eq__(self, other):
+        if not isinstance(other, PatchOperation):
+            return False
+        return self.operation == other.operation
+
+    def __ne__(self, other):
+        return not(self == other)
+
+    @property
+    def path(self):
+        return '/'.join(self.pointer.parts[:-1])
+
+    @property
+    def key(self):
+        try:
+            return int(self.pointer.parts[-1])
+        except ValueError:
+            return self.pointer.parts[-1]
+
+    @key.setter
+    def key(self, value):
+        self.pointer.parts[-1] = str(value)
+        self.location = self.pointer.path
+        self.operation['path'] = self.location
+
+
+class RemoveOperation(PatchOperation):
+    """Removes an object property or an array element."""
+
+    def apply(self, obj):
+        subobj, part = self.pointer.to_last(obj)
+
+        if isinstance(subobj, Sequence) and not isinstance(part, int):
+            raise JsonPointerException("invalid array index '{0}'".format(part))
+
+        try:
+            del subobj[part]
+        except (KeyError, IndexError) as ex:
+            msg = "can't remove a non-existent object '{0}'".format(part)
+            raise JsonPatchConflict(msg)
+
+        return obj
+
+    def _on_undo_remove(self, path, key):
+        if self.path == path:
+            if self.key >= key:
+                self.key += 1
+            else:
+                key -= 1
+        return key
+
+    def _on_undo_add(self, path, key):
+        if self.path == path:
+            if self.key > key:
+                self.key -= 1
+            else:
+                key -= 1
+        return key
+
+
+class AddOperation(PatchOperation):
+    """Adds an object property or an array element."""
+
+    def apply(self, obj):
+        try:
+            value = self.operation["value"]
+        except KeyError as ex:
+            raise InvalidJsonPatch(
+                "The operation does not contain a 'value' member")
+
+        subobj, part = self.pointer.to_last(obj)
+
+        if isinstance(subobj, MutableSequence):
+            if part == '-':
+                subobj.append(value)  # pylint: disable=E1103
+
+            elif part > len(subobj) or part < 0:
+                raise JsonPatchConflict("can't insert outside of list")
+
+            else:
+                subobj.insert(part, value)  # pylint: disable=E1103
+
+        elif isinstance(subobj, MutableMapping):
+            if part is None:
+                obj = value  # we're replacing the root
+            else:
+                subobj[part] = value
+
+        else:
+            if part is None:
+                raise TypeError("invalid document type {0}".format(type(subobj)))
+            else:
+                raise JsonPatchConflict("unable to fully resolve json pointer {0}, part {1}".format(self.location, part))
+        return obj
+
+    def _on_undo_remove(self, path, key):
+        if self.path == path:
+            if self.key > key:
+                self.key += 1
+            else:
+                key += 1
+        return key
+
+    def _on_undo_add(self, path, key):
+        if self.path == path:
+            if self.key > key:
+                self.key -= 1
+            else:
+                key += 1
+        return key
+
+
+class ReplaceOperation(PatchOperation):
+    """Replaces an object property or an array element by a new value."""
+
+    def apply(self, obj):
+        try:
+            value = self.operation["value"]
+        except KeyError as ex:
+            raise InvalidJsonPatch(
+                "The operation does not contain a 'value' member")
+
+        subobj, part = self.pointer.to_last(obj)
+
+        if part is None:
+            return value
+
+        if part == "-":
+            raise InvalidJsonPatch("'path' with '-' can't be applied to 'replace' operation")
+
+        if isinstance(subobj, MutableSequence):
+            if part >= len(subobj) or part < 0:
+                raise JsonPatchConflict("can't replace outside of list")
+
+        elif isinstance(subobj, MutableMapping):
+            if part not in subobj:
+                msg = "can't replace a non-existent object '{0}'".format(part)
+                raise JsonPatchConflict(msg)
+        else:
+            if part is None:
+                raise TypeError("invalid document type {0}".format(type(subobj)))
+            else:
+                raise JsonPatchConflict("unable to fully resolve json pointer {0}, part {1}".format(self.location, part))
+
+        subobj[part] = value
+        return obj
+
+    def _on_undo_remove(self, path, key):
+        return key
+
+    def _on_undo_add(self, path, key):
+        return key
+
+
+class MoveOperation(PatchOperation):
+    """Moves an object property or an array element to a new location."""
+
+    def apply(self, obj):
+        try:
+            if isinstance(self.operation['from'], self.pointer_cls):
+                from_ptr = self.operation['from']
+            else:
+                from_ptr = self.pointer_cls(self.operation['from'])
+        except KeyError as ex:
+            raise InvalidJsonPatch(
+                "The operation does not contain a 'from' member")
+
+        subobj, part = from_ptr.to_last(obj)
+        try:
+            value = subobj[part]
+        except (KeyError, IndexError) as ex:
+            raise JsonPatchConflict(str(ex))
+
+        # If source and target are equal, this is a no-op
+        if self.pointer == from_ptr:
+            return obj
+
+        if isinstance(subobj, MutableMapping) and \
+                self.pointer.contains(from_ptr):
+            raise JsonPatchConflict('Cannot move values into their own children')
+
+        obj = RemoveOperation({
+            'op': 'remove',
+            'path': self.operation['from']
+        }, pointer_cls=self.pointer_cls).apply(obj)
+
+        obj = AddOperation({
+            'op': 'add',
+            'path': self.location,
+            'value': value
+        }, pointer_cls=self.pointer_cls).apply(obj)
+
+        return obj
+
+    @property
+    def from_path(self):
+        from_ptr = self.pointer_cls(self.operation['from'])
+        return '/'.join(from_ptr.parts[:-1])
+
+    @property
+    def from_key(self):
+        from_ptr = self.pointer_cls(self.operation['from'])
+        try:
+            return int(from_ptr.parts[-1])
+        except TypeError:
+            return from_ptr.parts[-1]
+
+    @from_key.setter
+    def from_key(self, value):
+        from_ptr = self.pointer_cls(self.operation['from'])
+        from_ptr.parts[-1] = str(value)
+        self.operation['from'] = from_ptr.path
+
+    def _on_undo_remove(self, path, key):
+        if self.from_path == path:
+            if self.from_key >= key:
+                self.from_key += 1
+            else:
+                key -= 1
+        if self.path == path:
+            if self.key > key:
+                self.key += 1
+            else:
+                key += 1
+        return key
+
+    def _on_undo_add(self, path, key):
+        if self.from_path == path:
+            if self.from_key > key:
+                self.from_key -= 1
+            else:
+                key -= 1
+        if self.path == path:
+            if self.key > key:
+                self.key -= 1
+            else:
+                key += 1
+        return key
+
+
+class TestOperation(PatchOperation):
+    """Test value by specified location."""
+
+    def apply(self, obj):
+        try:
+            subobj, part = self.pointer.to_last(obj)
+            if part is None:
+                val = subobj
+            else:
+                val = self.pointer.walk(subobj, part)
+        except JsonPointerException as ex:
+            raise JsonPatchTestFailed(str(ex))
+
+        try:
+            value = self.operation['value']
+        except KeyError as ex:
+            raise InvalidJsonPatch(
+                "The operation does not contain a 'value' member")
+
+        if val != value:
+            msg = '{0} ({1}) is not equal to tested value {2} ({3})'
+            raise JsonPatchTestFailed(msg.format(val, type(val),
+                                                 value, type(value)))
+
+        return obj
+
+
+class CopyOperation(PatchOperation):
+    """ Copies an object property or an array element to a new location """
+
+    def apply(self, obj):
+        try:
+            from_ptr = self.pointer_cls(self.operation['from'])
+        except KeyError as ex:
+            raise InvalidJsonPatch(
+                "The operation does not contain a 'from' member")
+
+        subobj, part = from_ptr.to_last(obj)
+        try:
+            value = copy.deepcopy(subobj[part])
+        except (KeyError, IndexError) as ex:
+            raise JsonPatchConflict(str(ex))
+
+        obj = AddOperation({
+            'op': 'add',
+            'path': self.location,
+            'value': value
+        }, pointer_cls=self.pointer_cls).apply(obj)
+
+        return obj
+
+
+class JsonPatch(object):
+    json_dumper = staticmethod(json.dumps)
+    json_loader = staticmethod(_jsonloads)
+
+    operations = MappingProxyType({
+        'remove': RemoveOperation,
+        'add': AddOperation,
+        'replace': ReplaceOperation,
+        'move': MoveOperation,
+        'test': TestOperation,
+        'copy': CopyOperation,
+    })
+
+    """A JSON Patch is a list of Patch Operations.
+
+    >>> patch = JsonPatch([
+    ...     {'op': 'add', 'path': '/foo', 'value': 'bar'},
+    ...     {'op': 'add', 'path': '/baz', 'value': [1, 2, 3]},
+    ...     {'op': 'remove', 'path': '/baz/1'},
+    ...     {'op': 'test', 'path': '/baz', 'value': [1, 3]},
+    ...     {'op': 'replace', 'path': '/baz/0', 'value': 42},
+    ...     {'op': 'remove', 'path': '/baz/1'},
+    ... ])
+    >>> doc = {}
+    >>> result = patch.apply(doc)
+    >>> expected = {'foo': 'bar', 'baz': [42]}
+    >>> result == expected
+    True
+
+    JsonPatch object is iterable, so you can easily access each patch
+    statement in a loop:
+
+    >>> lpatch = list(patch)
+    >>> expected = {'op': 'add', 'path': '/foo', 'value': 'bar'}
+    >>> lpatch[0] == expected
+    True
+    >>> lpatch == patch.patch
+    True
+
+    Also JsonPatch could be converted directly to :class:`bool` if it contains
+    any operation statements:
+
+    >>> bool(patch)
+    True
+    >>> bool(JsonPatch([]))
+    False
+
+    This behavior is very handy with :func:`make_patch` to write more readable
+    code:
+
+    >>> old = {'foo': 'bar', 'numbers': [1, 3, 4, 8]}
+    >>> new = {'baz': 'qux', 'numbers': [1, 4, 7]}
+    >>> patch = make_patch(old, new)
+    >>> if patch:
+    ...     # document have changed, do something useful
+    ...     patch.apply(old)    #doctest: +ELLIPSIS
+    {...}
+    """
+    def __init__(self, patch, pointer_cls=JsonPointer):
+        self.patch = patch
+        self.pointer_cls = pointer_cls
+
+        # Verify that the structure of the patch document
+        # is correct by retrieving each patch element.
+        # Much of the validation is done in the initializer
+        # though some is delayed until the patch is applied.
+        for op in self.patch:
+            # We're only checking for basestring in the following check
+            # for two reasons:
+            #
+            # - It should come from JSON, which only allows strings as
+            #   dictionary keys, so having a string here unambiguously means
+            #   someone used: {"op": ..., ...} instead of [{"op": ..., ...}].
+            #
+            # - There's no possible false positive: if someone give a sequence
+            #   of mappings, this won't raise.
+            if isinstance(op, basestring):
+                raise InvalidJsonPatch("Document is expected to be sequence of "
+                                       "operations, got a sequence of strings.")
+
+            self._get_operation(op)
+
+    def __str__(self):
+        """str(self) -> self.to_string()"""
+        return self.to_string()
+
+    def __bool__(self):
+        return bool(self.patch)
+
+    __nonzero__ = __bool__
+
+    def __iter__(self):
+        return iter(self.patch)
+
+    def __hash__(self):
+        return hash(tuple(self._ops))
+
+    def __eq__(self, other):
+        if not isinstance(other, JsonPatch):
+            return False
+        return self._ops == other._ops
+
+    def __ne__(self, other):
+        return not(self == other)
+
+    @classmethod
+    def from_string(cls, patch_str, loads=None, pointer_cls=JsonPointer):
+        """Creates JsonPatch instance from string source.
+
+        :param patch_str: JSON patch as raw string.
+        :type patch_str: str
+
+        :param loads: A function of one argument that loads a serialized
+                      JSON string.
+        :type loads: function
+
+        :param pointer_cls: JSON pointer class to use.
+        :type pointer_cls: Type[JsonPointer]
+
+        :return: :class:`JsonPatch` instance.
+        """
+        json_loader = loads or cls.json_loader
+        patch = json_loader(patch_str)
+        return cls(patch, pointer_cls=pointer_cls)
+
+    @classmethod
+    def from_diff(
+            cls, src, dst, optimization=True, dumps=None,
+            pointer_cls=JsonPointer,
+    ):
+        """Creates JsonPatch instance based on comparison of two document
+        objects. Json patch would be created for `src` argument against `dst`
+        one.
+
+        :param src: Data source document object.
+        :type src: dict
+
+        :param dst: Data source document object.
+        :type dst: dict
+
+        :param dumps: A function of one argument that produces a serialized
+                      JSON string.
+        :type dumps: function
+
+        :param pointer_cls: JSON pointer class to use.
+        :type pointer_cls: Type[JsonPointer]
+
+        :return: :class:`JsonPatch` instance.
+
+        >>> src = {'foo': 'bar', 'numbers': [1, 3, 4, 8]}
+        >>> dst = {'baz': 'qux', 'numbers': [1, 4, 7]}
+        >>> patch = JsonPatch.from_diff(src, dst)
+        >>> new = patch.apply(src)
+        >>> new == dst
+        True
+        """
+        json_dumper = dumps or cls.json_dumper
+        builder = DiffBuilder(src, dst, json_dumper, pointer_cls=pointer_cls)
+        builder._compare_values('', None, src, dst)
+        ops = list(builder.execute())
+        return cls(ops, pointer_cls=pointer_cls)
+
+    def to_string(self, dumps=None):
+        """Returns patch set as JSON string."""
+        json_dumper = dumps or self.json_dumper
+        return json_dumper(self.patch)
+
+    @property
+    def _ops(self):
+        return tuple(map(self._get_operation, self.patch))
+
+    def apply(self, obj, in_place=False):
+        """Applies the patch to a given object.
+
+        :param obj: Document object.
+        :type obj: dict
+
+        :param in_place: Tweaks the way how patch would be applied - directly to
+                         specified `obj` or to its copy.
+        :type in_place: bool
+
+        :return: Modified `obj`.
+        """
+
+        if not in_place:
+            obj = copy.deepcopy(obj)
+
+        for operation in self._ops:
+            obj = operation.apply(obj)
+
+        return obj
+
+    def _get_operation(self, operation):
+        if 'op' not in operation:
+            raise InvalidJsonPatch("Operation does not contain 'op' member")
+
+        op = operation['op']
+
+        if not isinstance(op, basestring):
+            raise InvalidJsonPatch("Operation's op must be a string")
+
+        if op not in self.operations:
+            raise InvalidJsonPatch("Unknown operation {0!r}".format(op))
+
+        cls = self.operations[op]
+        return cls(operation, pointer_cls=self.pointer_cls)
+
+
+class DiffBuilder(object):
+
+    def __init__(self, src_doc, dst_doc, dumps=json.dumps, pointer_cls=JsonPointer):
+        self.dumps = dumps
+        self.pointer_cls = pointer_cls
+        self.index_storage = [{}, {}]
+        self.index_storage2 = [[], []]
+        self.__root = root = []
+        self.src_doc = src_doc
+        self.dst_doc = dst_doc
+        root[:] = [root, root, None]
+
+    def store_index(self, value, index, st):
+        typed_key = (value, type(value))
+        try:
+            storage = self.index_storage[st]
+            stored = storage.get(typed_key)
+            if stored is None:
+                storage[typed_key] = [index]
+            else:
+                storage[typed_key].append(index)
+
+        except TypeError:
+            self.index_storage2[st].append((typed_key, index))
+
+    def take_index(self, value, st):
+        typed_key = (value, type(value))
+        try:
+            stored = self.index_storage[st].get(typed_key)
+            if stored:
+                return stored.pop()
+
+        except TypeError:
+            storage = self.index_storage2[st]
+            for i in range(len(storage)-1, -1, -1):
+                if storage[i][0] == typed_key:
+                    return storage.pop(i)[1]
+
+    def insert(self, op):
+        root = self.__root
+        last = root[0]
+        last[1] = root[0] = [last, root, op]
+        return root[0]
+
+    def remove(self, index):
+        link_prev, link_next, _ = index
+        link_prev[1] = link_next
+        link_next[0] = link_prev
+        index[:] = []
+
+    def iter_from(self, start):
+        root = self.__root
+        curr = start[1]
+        while curr is not root:
+            yield curr[2]
+            curr = curr[1]
+
+    def __iter__(self):
+        root = self.__root
+        curr = root[1]
+        while curr is not root:
+            yield curr[2]
+            curr = curr[1]
+
+    def execute(self):
+        root = self.__root
+        curr = root[1]
+        while curr is not root:
+            if curr[1] is not root:
+                op_first, op_second = curr[2], curr[1][2]
+                if op_first.location == op_second.location and \
+                        type(op_first) == RemoveOperation and \
+                        type(op_second) == AddOperation:
+                    yield ReplaceOperation({
+                        'op': 'replace',
+                        'path': op_second.location,
+                        'value': op_second.operation['value'],
+                    }, pointer_cls=self.pointer_cls).operation
+                    curr = curr[1][1]
+                    continue
+
+            yield curr[2].operation
+            curr = curr[1]
+
+    def _item_added(self, path, key, item):
+        index = self.take_index(item, _ST_REMOVE)
+        if index is not None:
+            op = index[2]
+            if type(op.key) == int and type(key) == int:
+                for v in self.iter_from(index):
+                    op.key = v._on_undo_remove(op.path, op.key)
+
+            self.remove(index)
+            if op.location != _path_join(path, key):
+                new_op = MoveOperation({
+                    'op': 'move',
+                    'from': op.location,
+                    'path': _path_join(path, key),
+                }, pointer_cls=self.pointer_cls)
+                self.insert(new_op)
+        else:
+            new_op = AddOperation({
+                'op': 'add',
+                'path': _path_join(path, key),
+                'value': item,
+            }, pointer_cls=self.pointer_cls)
+            new_index = self.insert(new_op)
+            self.store_index(item, new_index, _ST_ADD)
+
+    def _item_removed(self, path, key, item):
+        new_op = RemoveOperation({
+            'op': 'remove',
+            'path': _path_join(path, key),
+        }, pointer_cls=self.pointer_cls)
+        index = self.take_index(item, _ST_ADD)
+        new_index = self.insert(new_op)
+        if index is not None:
+            op = index[2]
+            # We can't rely on the op.key type since PatchOperation casts
+            # the .key property to int and this path wrongly ends up being taken
+            # for numeric string dict keys while the intention is to only handle lists.
+            # So we do an explicit check on the item affected by the op instead.
+            added_item = op.pointer.to_last(self.dst_doc)[0]
+            if type(added_item) == list:
+                for v in self.iter_from(index):
+                    op.key = v._on_undo_add(op.path, op.key)
+
+            self.remove(index)
+            if new_op.location != op.location:
+                new_op = MoveOperation({
+                    'op': 'move',
+                    'from': new_op.location,
+                    'path': op.location,
+                }, pointer_cls=self.pointer_cls)
+                new_index[2] = new_op
+
+            else:
+                self.remove(new_index)
+
+        else:
+            self.store_index(item, new_index, _ST_REMOVE)
+
+    def _item_replaced(self, path, key, item):
+        self.insert(ReplaceOperation({
+            'op': 'replace',
+            'path': _path_join(path, key),
+            'value': item,
+        }, pointer_cls=self.pointer_cls))
+
+    def _compare_dicts(self, path, src, dst):
+        src_keys = set(src.keys())
+        dst_keys = set(dst.keys())
+        added_keys = dst_keys - src_keys
+        removed_keys = src_keys - dst_keys
+
+        for key in removed_keys:
+            self._item_removed(path, str(key), src[key])
+
+        for key in added_keys:
+            self._item_added(path, str(key), dst[key])
+
+        for key in src_keys & dst_keys:
+            self._compare_values(path, key, src[key], dst[key])
+
+    def _compare_lists(self, path, src, dst):
+        len_src, len_dst = len(src), len(dst)
+        max_len = max(len_src, len_dst)
+        min_len = min(len_src, len_dst)
+        for key in range(max_len):
+            if key < min_len:
+                old, new = src[key], dst[key]
+                if old == new:
+                    continue
+
+                elif isinstance(old, MutableMapping) and \
+                    isinstance(new, MutableMapping):
+                    self._compare_dicts(_path_join(path, key), old, new)
+
+                elif isinstance(old, MutableSequence) and \
+                        isinstance(new, MutableSequence):
+                    self._compare_lists(_path_join(path, key), old, new)
+
+                else:
+                    self._item_removed(path, key, old)
+                    self._item_added(path, key, new)
+
+            elif len_src > len_dst:
+                self._item_removed(path, len_dst, src[key])
+
+            else:
+                self._item_added(path, key, dst[key])
+
+    def _compare_values(self, path, key, src, dst):
+        if isinstance(src, MutableMapping) and \
+                isinstance(dst, MutableMapping):
+            self._compare_dicts(_path_join(path, key), src, dst)
+
+        elif isinstance(src, MutableSequence) and \
+                isinstance(dst, MutableSequence):
+            self._compare_lists(_path_join(path, key), src, dst)
+
+        # To ensure we catch changes to JSON, we can't rely on a simple
+        # src == dst, because it would not recognize the difference between
+        # 1 and True, among other things. Using json.dumps is the most
+        # fool-proof way to ensure we catch type changes that matter to JSON
+        # and ignore those that don't. The performance of this could be
+        # improved by doing more direct type checks, but we'd need to be
+        # careful to accept type changes that don't matter when JSONified.
+        elif self.dumps(src) == self.dumps(dst):
+            return
+
+        else:
+            self._item_replaced(path, key, dst)
+
+
+def _path_join(path, key):
+    if key is None:
+        return path
+
+    return path + '/' + str(key).replace('~', '~0').replace('/', '~1')