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Diffstat (limited to 'venv/Lib/site-packages/astroid/inference.py')
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diff --git a/venv/Lib/site-packages/astroid/inference.py b/venv/Lib/site-packages/astroid/inference.py deleted file mode 100644 index 77c6b1d..0000000 --- a/venv/Lib/site-packages/astroid/inference.py +++ /dev/null @@ -1,943 +0,0 @@ -# -*- coding: utf-8 -*- -# Copyright (c) 2006-2011, 2013-2014 LOGILAB S.A. (Paris, FRANCE) <contact@logilab.fr> -# Copyright (c) 2012 FELD Boris <lothiraldan@gmail.com> -# Copyright (c) 2013-2014 Google, Inc. -# Copyright (c) 2014-2018 Claudiu Popa <pcmanticore@gmail.com> -# Copyright (c) 2014 Eevee (Alex Munroe) <amunroe@yelp.com> -# Copyright (c) 2015-2016 Ceridwen <ceridwenv@gmail.com> -# Copyright (c) 2015 Dmitry Pribysh <dmand@yandex.ru> -# Copyright (c) 2016 Jakub Wilk <jwilk@jwilk.net> -# Copyright (c) 2017 Michał Masłowski <m.maslowski@clearcode.cc> -# Copyright (c) 2017 Calen Pennington <cale@edx.org> -# Copyright (c) 2017 Łukasz Rogalski <rogalski.91@gmail.com> -# Copyright (c) 2018 Bryce Guinta <bryce.paul.guinta@gmail.com> -# Copyright (c) 2018 Nick Drozd <nicholasdrozd@gmail.com> -# Copyright (c) 2018 Ashley Whetter <ashley@awhetter.co.uk> -# Copyright (c) 2018 HoverHell <hoverhell@gmail.com> - -# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html -# For details: https://github.com/PyCQA/astroid/blob/master/COPYING.LESSER - -"""this module contains a set of functions to handle inference on astroid trees -""" - -import functools -import itertools -import operator - -from astroid import bases -from astroid import context as contextmod -from astroid import exceptions -from astroid import decorators -from astroid import helpers -from astroid import manager -from astroid import nodes -from astroid.interpreter import dunder_lookup -from astroid import protocols -from astroid import util - - -MANAGER = manager.AstroidManager() - - -# .infer method ############################################################### - - -def infer_end(self, context=None): - """inference's end for node such as Module, ClassDef, FunctionDef, - Const... - - """ - yield self - - -nodes.Module._infer = infer_end -nodes.ClassDef._infer = infer_end -nodes.FunctionDef._infer = infer_end -nodes.Lambda._infer = infer_end -nodes.Const._infer = infer_end -nodes.Slice._infer = infer_end - - -def _infer_sequence_helper(node, context=None): - """Infer all values based on _BaseContainer.elts""" - values = [] - - for elt in node.elts: - if isinstance(elt, nodes.Starred): - starred = helpers.safe_infer(elt.value, context) - if not starred: - raise exceptions.InferenceError(node=node, context=context) - if not hasattr(starred, "elts"): - raise exceptions.InferenceError(node=node, context=context) - values.extend(_infer_sequence_helper(starred)) - elif isinstance(elt, nodes.NamedExpr): - value = helpers.safe_infer(elt.value, context) - if not value: - raise exceptions.InferenceError(node=node, context=context) - values.append(value) - else: - values.append(elt) - return values - - -@decorators.raise_if_nothing_inferred -def infer_sequence(self, context=None): - has_starred_named_expr = any( - isinstance(e, (nodes.Starred, nodes.NamedExpr)) for e in self.elts - ) - if has_starred_named_expr: - values = _infer_sequence_helper(self, context) - new_seq = type(self)( - lineno=self.lineno, col_offset=self.col_offset, parent=self.parent - ) - new_seq.postinit(values) - - yield new_seq - else: - yield self - - -nodes.List._infer = infer_sequence -nodes.Tuple._infer = infer_sequence -nodes.Set._infer = infer_sequence - - -def infer_map(self, context=None): - if not any(isinstance(k, nodes.DictUnpack) for k, _ in self.items): - yield self - else: - items = _infer_map(self, context) - new_seq = type(self)(self.lineno, self.col_offset, self.parent) - new_seq.postinit(list(items.items())) - yield new_seq - - -def _update_with_replacement(lhs_dict, rhs_dict): - """Delete nodes that equate to duplicate keys - - Since an astroid node doesn't 'equal' another node with the same value, - this function uses the as_string method to make sure duplicate keys - don't get through - - Note that both the key and the value are astroid nodes - - Fixes issue with DictUnpack causing duplicte keys - in inferred Dict items - - :param dict(nodes.NodeNG, nodes.NodeNG) lhs_dict: Dictionary to 'merge' nodes into - :param dict(nodes.NodeNG, nodes.NodeNG) rhs_dict: Dictionary with nodes to pull from - :return dict(nodes.NodeNG, nodes.NodeNG): merged dictionary of nodes - """ - combined_dict = itertools.chain(lhs_dict.items(), rhs_dict.items()) - # Overwrite keys which have the same string values - string_map = {key.as_string(): (key, value) for key, value in combined_dict} - # Return to dictionary - return dict(string_map.values()) - - -def _infer_map(node, context): - """Infer all values based on Dict.items""" - values = {} - for name, value in node.items: - if isinstance(name, nodes.DictUnpack): - double_starred = helpers.safe_infer(value, context) - if not double_starred: - raise exceptions.InferenceError - if not isinstance(double_starred, nodes.Dict): - raise exceptions.InferenceError(node=node, context=context) - unpack_items = _infer_map(double_starred, context) - values = _update_with_replacement(values, unpack_items) - else: - key = helpers.safe_infer(name, context=context) - value = helpers.safe_infer(value, context=context) - if any(not elem for elem in (key, value)): - raise exceptions.InferenceError(node=node, context=context) - values = _update_with_replacement(values, {key: value}) - return values - - -nodes.Dict._infer = infer_map - - -def _higher_function_scope(node): - """ Search for the first function which encloses the given - scope. This can be used for looking up in that function's - scope, in case looking up in a lower scope for a particular - name fails. - - :param node: A scope node. - :returns: - ``None``, if no parent function scope was found, - otherwise an instance of :class:`astroid.scoped_nodes.Function`, - which encloses the given node. - """ - current = node - while current.parent and not isinstance(current.parent, nodes.FunctionDef): - current = current.parent - if current and current.parent: - return current.parent - return None - - -def infer_name(self, context=None): - """infer a Name: use name lookup rules""" - frame, stmts = self.lookup(self.name) - if not stmts: - # Try to see if the name is enclosed in a nested function - # and use the higher (first function) scope for searching. - parent_function = _higher_function_scope(self.scope()) - if parent_function: - _, stmts = parent_function.lookup(self.name) - - if not stmts: - raise exceptions.NameInferenceError( - name=self.name, scope=self.scope(), context=context - ) - context = contextmod.copy_context(context) - context.lookupname = self.name - return bases._infer_stmts(stmts, context, frame) - - -# pylint: disable=no-value-for-parameter -nodes.Name._infer = decorators.raise_if_nothing_inferred( - decorators.path_wrapper(infer_name) -) -nodes.AssignName.infer_lhs = infer_name # won't work with a path wrapper - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_call(self, context=None): - """infer a Call node by trying to guess what the function returns""" - callcontext = contextmod.copy_context(context) - callcontext.callcontext = contextmod.CallContext( - args=self.args, keywords=self.keywords - ) - callcontext.boundnode = None - if context is not None: - callcontext.extra_context = _populate_context_lookup(self, context.clone()) - - for callee in self.func.infer(context): - if callee is util.Uninferable: - yield callee - continue - try: - if hasattr(callee, "infer_call_result"): - yield from callee.infer_call_result(caller=self, context=callcontext) - except exceptions.InferenceError: - continue - return dict(node=self, context=context) - - -nodes.Call._infer = infer_call - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_import(self, context=None, asname=True): - """infer an Import node: return the imported module/object""" - name = context.lookupname - if name is None: - raise exceptions.InferenceError(node=self, context=context) - - try: - if asname: - yield self.do_import_module(self.real_name(name)) - else: - yield self.do_import_module(name) - except exceptions.AstroidBuildingError as exc: - raise exceptions.InferenceError(node=self, context=context) from exc - - -nodes.Import._infer = infer_import - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_import_from(self, context=None, asname=True): - """infer a ImportFrom node: return the imported module/object""" - name = context.lookupname - if name is None: - raise exceptions.InferenceError(node=self, context=context) - if asname: - name = self.real_name(name) - - try: - module = self.do_import_module() - except exceptions.AstroidBuildingError as exc: - raise exceptions.InferenceError(node=self, context=context) from exc - - try: - context = contextmod.copy_context(context) - context.lookupname = name - stmts = module.getattr(name, ignore_locals=module is self.root()) - return bases._infer_stmts(stmts, context) - except exceptions.AttributeInferenceError as error: - raise exceptions.InferenceError( - error.message, target=self, attribute=name, context=context - ) from error - - -nodes.ImportFrom._infer = infer_import_from - - -def infer_attribute(self, context=None): - """infer an Attribute node by using getattr on the associated object""" - for owner in self.expr.infer(context): - if owner is util.Uninferable: - yield owner - continue - - if context and context.boundnode: - # This handles the situation where the attribute is accessed through a subclass - # of a base class and the attribute is defined at the base class's level, - # by taking in consideration a redefinition in the subclass. - if isinstance(owner, bases.Instance) and isinstance( - context.boundnode, bases.Instance - ): - try: - if helpers.is_subtype( - helpers.object_type(context.boundnode), - helpers.object_type(owner), - ): - owner = context.boundnode - except exceptions._NonDeducibleTypeHierarchy: - # Can't determine anything useful. - pass - - try: - context.boundnode = owner - yield from owner.igetattr(self.attrname, context) - context.boundnode = None - except (exceptions.AttributeInferenceError, exceptions.InferenceError): - context.boundnode = None - except AttributeError: - # XXX method / function - context.boundnode = None - return dict(node=self, context=context) - - -nodes.Attribute._infer = decorators.raise_if_nothing_inferred( - decorators.path_wrapper(infer_attribute) -) -# won't work with a path wrapper -nodes.AssignAttr.infer_lhs = decorators.raise_if_nothing_inferred(infer_attribute) - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_global(self, context=None): - if context.lookupname is None: - raise exceptions.InferenceError(node=self, context=context) - try: - return bases._infer_stmts(self.root().getattr(context.lookupname), context) - except exceptions.AttributeInferenceError as error: - raise exceptions.InferenceError( - error.message, target=self, attribute=context.lookupname, context=context - ) from error - - -nodes.Global._infer = infer_global - - -_SUBSCRIPT_SENTINEL = object() - - -@decorators.raise_if_nothing_inferred -def infer_subscript(self, context=None): - """Inference for subscripts - - We're understanding if the index is a Const - or a slice, passing the result of inference - to the value's `getitem` method, which should - handle each supported index type accordingly. - """ - - found_one = False - for value in self.value.infer(context): - if value is util.Uninferable: - yield util.Uninferable - return None - for index in self.slice.infer(context): - if index is util.Uninferable: - yield util.Uninferable - return None - - # Try to deduce the index value. - index_value = _SUBSCRIPT_SENTINEL - if value.__class__ == bases.Instance: - index_value = index - else: - if index.__class__ == bases.Instance: - instance_as_index = helpers.class_instance_as_index(index) - if instance_as_index: - index_value = instance_as_index - else: - index_value = index - if index_value is _SUBSCRIPT_SENTINEL: - raise exceptions.InferenceError(node=self, context=context) - - try: - assigned = value.getitem(index_value, context) - except ( - exceptions.AstroidTypeError, - exceptions.AstroidIndexError, - exceptions.AttributeInferenceError, - AttributeError, - ) as exc: - raise exceptions.InferenceError(node=self, context=context) from exc - - # Prevent inferring if the inferred subscript - # is the same as the original subscripted object. - if self is assigned or assigned is util.Uninferable: - yield util.Uninferable - return None - yield from assigned.infer(context) - found_one = True - - if found_one: - return dict(node=self, context=context) - return None - - -nodes.Subscript._infer = decorators.path_wrapper(infer_subscript) -nodes.Subscript.infer_lhs = infer_subscript - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def _infer_boolop(self, context=None): - """Infer a boolean operation (and / or / not). - - The function will calculate the boolean operation - for all pairs generated through inference for each component - node. - """ - values = self.values - if self.op == "or": - predicate = operator.truth - else: - predicate = operator.not_ - - try: - values = [value.infer(context=context) for value in values] - except exceptions.InferenceError: - yield util.Uninferable - return None - - for pair in itertools.product(*values): - if any(item is util.Uninferable for item in pair): - # Can't infer the final result, just yield Uninferable. - yield util.Uninferable - continue - - bool_values = [item.bool_value() for item in pair] - if any(item is util.Uninferable for item in bool_values): - # Can't infer the final result, just yield Uninferable. - yield util.Uninferable - continue - - # Since the boolean operations are short circuited operations, - # this code yields the first value for which the predicate is True - # and if no value respected the predicate, then the last value will - # be returned (or Uninferable if there was no last value). - # This is conforming to the semantics of `and` and `or`: - # 1 and 0 -> 1 - # 0 and 1 -> 0 - # 1 or 0 -> 1 - # 0 or 1 -> 1 - value = util.Uninferable - for value, bool_value in zip(pair, bool_values): - if predicate(bool_value): - yield value - break - else: - yield value - - return dict(node=self, context=context) - - -nodes.BoolOp._infer = _infer_boolop - - -# UnaryOp, BinOp and AugAssign inferences - - -def _filter_operation_errors(self, infer_callable, context, error): - for result in infer_callable(self, context): - if isinstance(result, error): - # For the sake of .infer(), we don't care about operation - # errors, which is the job of pylint. So return something - # which shows that we can't infer the result. - yield util.Uninferable - else: - yield result - - -def _infer_unaryop(self, context=None): - """Infer what an UnaryOp should return when evaluated.""" - for operand in self.operand.infer(context): - try: - yield operand.infer_unary_op(self.op) - except TypeError as exc: - # The operand doesn't support this operation. - yield util.BadUnaryOperationMessage(operand, self.op, exc) - except AttributeError as exc: - meth = protocols.UNARY_OP_METHOD[self.op] - if meth is None: - # `not node`. Determine node's boolean - # value and negate its result, unless it is - # Uninferable, which will be returned as is. - bool_value = operand.bool_value() - if bool_value is not util.Uninferable: - yield nodes.const_factory(not bool_value) - else: - yield util.Uninferable - else: - if not isinstance(operand, (bases.Instance, nodes.ClassDef)): - # The operation was used on something which - # doesn't support it. - yield util.BadUnaryOperationMessage(operand, self.op, exc) - continue - - try: - try: - methods = dunder_lookup.lookup(operand, meth) - except exceptions.AttributeInferenceError: - yield util.BadUnaryOperationMessage(operand, self.op, exc) - continue - - meth = methods[0] - inferred = next(meth.infer(context=context)) - if inferred is util.Uninferable or not inferred.callable(): - continue - - context = contextmod.copy_context(context) - context.callcontext = contextmod.CallContext(args=[operand]) - call_results = inferred.infer_call_result(self, context=context) - result = next(call_results, None) - if result is None: - # Failed to infer, return the same type. - yield operand - else: - yield result - except exceptions.AttributeInferenceError as exc: - # The unary operation special method was not found. - yield util.BadUnaryOperationMessage(operand, self.op, exc) - except exceptions.InferenceError: - yield util.Uninferable - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_unaryop(self, context=None): - """Infer what an UnaryOp should return when evaluated.""" - yield from _filter_operation_errors( - self, _infer_unaryop, context, util.BadUnaryOperationMessage - ) - return dict(node=self, context=context) - - -nodes.UnaryOp._infer_unaryop = _infer_unaryop -nodes.UnaryOp._infer = infer_unaryop - - -def _is_not_implemented(const): - """Check if the given const node is NotImplemented.""" - return isinstance(const, nodes.Const) and const.value is NotImplemented - - -def _invoke_binop_inference(instance, opnode, op, other, context, method_name): - """Invoke binary operation inference on the given instance.""" - methods = dunder_lookup.lookup(instance, method_name) - context = contextmod.bind_context_to_node(context, instance) - method = methods[0] - inferred = next(method.infer(context=context)) - if inferred is util.Uninferable: - raise exceptions.InferenceError - return instance.infer_binary_op(opnode, op, other, context, inferred) - - -def _aug_op(instance, opnode, op, other, context, reverse=False): - """Get an inference callable for an augmented binary operation.""" - method_name = protocols.AUGMENTED_OP_METHOD[op] - return functools.partial( - _invoke_binop_inference, - instance=instance, - op=op, - opnode=opnode, - other=other, - context=context, - method_name=method_name, - ) - - -def _bin_op(instance, opnode, op, other, context, reverse=False): - """Get an inference callable for a normal binary operation. - - If *reverse* is True, then the reflected method will be used instead. - """ - if reverse: - method_name = protocols.REFLECTED_BIN_OP_METHOD[op] - else: - method_name = protocols.BIN_OP_METHOD[op] - return functools.partial( - _invoke_binop_inference, - instance=instance, - op=op, - opnode=opnode, - other=other, - context=context, - method_name=method_name, - ) - - -def _get_binop_contexts(context, left, right): - """Get contexts for binary operations. - - This will return two inference contexts, the first one - for x.__op__(y), the other one for y.__rop__(x), where - only the arguments are inversed. - """ - # The order is important, since the first one should be - # left.__op__(right). - for arg in (right, left): - new_context = context.clone() - new_context.callcontext = contextmod.CallContext(args=[arg]) - new_context.boundnode = None - yield new_context - - -def _same_type(type1, type2): - """Check if type1 is the same as type2.""" - return type1.qname() == type2.qname() - - -def _get_binop_flow( - left, left_type, binary_opnode, right, right_type, context, reverse_context -): - """Get the flow for binary operations. - - The rules are a bit messy: - - * if left and right have the same type, then only one - method will be called, left.__op__(right) - * if left and right are unrelated typewise, then first - left.__op__(right) is tried and if this does not exist - or returns NotImplemented, then right.__rop__(left) is tried. - * if left is a subtype of right, then only left.__op__(right) - is tried. - * if left is a supertype of right, then right.__rop__(left) - is first tried and then left.__op__(right) - """ - op = binary_opnode.op - if _same_type(left_type, right_type): - methods = [_bin_op(left, binary_opnode, op, right, context)] - elif helpers.is_subtype(left_type, right_type): - methods = [_bin_op(left, binary_opnode, op, right, context)] - elif helpers.is_supertype(left_type, right_type): - methods = [ - _bin_op(right, binary_opnode, op, left, reverse_context, reverse=True), - _bin_op(left, binary_opnode, op, right, context), - ] - else: - methods = [ - _bin_op(left, binary_opnode, op, right, context), - _bin_op(right, binary_opnode, op, left, reverse_context, reverse=True), - ] - return methods - - -def _get_aug_flow( - left, left_type, aug_opnode, right, right_type, context, reverse_context -): - """Get the flow for augmented binary operations. - - The rules are a bit messy: - - * if left and right have the same type, then left.__augop__(right) - is first tried and then left.__op__(right). - * if left and right are unrelated typewise, then - left.__augop__(right) is tried, then left.__op__(right) - is tried and then right.__rop__(left) is tried. - * if left is a subtype of right, then left.__augop__(right) - is tried and then left.__op__(right). - * if left is a supertype of right, then left.__augop__(right) - is tried, then right.__rop__(left) and then - left.__op__(right) - """ - bin_op = aug_opnode.op.strip("=") - aug_op = aug_opnode.op - if _same_type(left_type, right_type): - methods = [ - _aug_op(left, aug_opnode, aug_op, right, context), - _bin_op(left, aug_opnode, bin_op, right, context), - ] - elif helpers.is_subtype(left_type, right_type): - methods = [ - _aug_op(left, aug_opnode, aug_op, right, context), - _bin_op(left, aug_opnode, bin_op, right, context), - ] - elif helpers.is_supertype(left_type, right_type): - methods = [ - _aug_op(left, aug_opnode, aug_op, right, context), - _bin_op(right, aug_opnode, bin_op, left, reverse_context, reverse=True), - _bin_op(left, aug_opnode, bin_op, right, context), - ] - else: - methods = [ - _aug_op(left, aug_opnode, aug_op, right, context), - _bin_op(left, aug_opnode, bin_op, right, context), - _bin_op(right, aug_opnode, bin_op, left, reverse_context, reverse=True), - ] - return methods - - -def _infer_binary_operation(left, right, binary_opnode, context, flow_factory): - """Infer a binary operation between a left operand and a right operand - - This is used by both normal binary operations and augmented binary - operations, the only difference is the flow factory used. - """ - - context, reverse_context = _get_binop_contexts(context, left, right) - left_type = helpers.object_type(left) - right_type = helpers.object_type(right) - methods = flow_factory( - left, left_type, binary_opnode, right, right_type, context, reverse_context - ) - for method in methods: - try: - results = list(method()) - except AttributeError: - continue - except exceptions.AttributeInferenceError: - continue - except exceptions.InferenceError: - yield util.Uninferable - return - else: - if any(result is util.Uninferable for result in results): - yield util.Uninferable - return - - if all(map(_is_not_implemented, results)): - continue - not_implemented = sum( - 1 for result in results if _is_not_implemented(result) - ) - if not_implemented and not_implemented != len(results): - # Can't infer yet what this is. - yield util.Uninferable - return - - yield from results - return - # The operation doesn't seem to be supported so let the caller know about it - yield util.BadBinaryOperationMessage(left_type, binary_opnode.op, right_type) - - -def _infer_binop(self, context): - """Binary operation inference logic.""" - left = self.left - right = self.right - - # we use two separate contexts for evaluating lhs and rhs because - # 1. evaluating lhs may leave some undesired entries in context.path - # which may not let us infer right value of rhs - context = context or contextmod.InferenceContext() - lhs_context = contextmod.copy_context(context) - rhs_context = contextmod.copy_context(context) - lhs_iter = left.infer(context=lhs_context) - rhs_iter = right.infer(context=rhs_context) - for lhs, rhs in itertools.product(lhs_iter, rhs_iter): - if any(value is util.Uninferable for value in (rhs, lhs)): - # Don't know how to process this. - yield util.Uninferable - return - - try: - yield from _infer_binary_operation(lhs, rhs, self, context, _get_binop_flow) - except exceptions._NonDeducibleTypeHierarchy: - yield util.Uninferable - - -@decorators.yes_if_nothing_inferred -@decorators.path_wrapper -def infer_binop(self, context=None): - return _filter_operation_errors( - self, _infer_binop, context, util.BadBinaryOperationMessage - ) - - -nodes.BinOp._infer_binop = _infer_binop -nodes.BinOp._infer = infer_binop - - -def _infer_augassign(self, context=None): - """Inference logic for augmented binary operations.""" - if context is None: - context = contextmod.InferenceContext() - - rhs_context = context.clone() - - lhs_iter = self.target.infer_lhs(context=context) - rhs_iter = self.value.infer(context=rhs_context) - for lhs, rhs in itertools.product(lhs_iter, rhs_iter): - if any(value is util.Uninferable for value in (rhs, lhs)): - # Don't know how to process this. - yield util.Uninferable - return - - try: - yield from _infer_binary_operation( - left=lhs, - right=rhs, - binary_opnode=self, - context=context, - flow_factory=_get_aug_flow, - ) - except exceptions._NonDeducibleTypeHierarchy: - yield util.Uninferable - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_augassign(self, context=None): - return _filter_operation_errors( - self, _infer_augassign, context, util.BadBinaryOperationMessage - ) - - -nodes.AugAssign._infer_augassign = _infer_augassign -nodes.AugAssign._infer = infer_augassign - -# End of binary operation inference. - - -@decorators.raise_if_nothing_inferred -def infer_arguments(self, context=None): - name = context.lookupname - if name is None: - raise exceptions.InferenceError(node=self, context=context) - return protocols._arguments_infer_argname(self, name, context) - - -nodes.Arguments._infer = infer_arguments - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_assign(self, context=None): - """infer a AssignName/AssignAttr: need to inspect the RHS part of the - assign node - """ - stmt = self.statement() - if isinstance(stmt, nodes.AugAssign): - return stmt.infer(context) - - stmts = list(self.assigned_stmts(context=context)) - return bases._infer_stmts(stmts, context) - - -nodes.AssignName._infer = infer_assign -nodes.AssignAttr._infer = infer_assign - - -@decorators.raise_if_nothing_inferred -@decorators.path_wrapper -def infer_empty_node(self, context=None): - if not self.has_underlying_object(): - yield util.Uninferable - else: - try: - yield from MANAGER.infer_ast_from_something(self.object, context=context) - except exceptions.AstroidError: - yield util.Uninferable - - -nodes.EmptyNode._infer = infer_empty_node - - -@decorators.raise_if_nothing_inferred -def infer_index(self, context=None): - return self.value.infer(context) - - -nodes.Index._infer = infer_index - -# TODO: move directly into bases.Instance when the dependency hell -# will be solved. -def instance_getitem(self, index, context=None): - # Rewrap index to Const for this case - new_context = contextmod.bind_context_to_node(context, self) - if not context: - context = new_context - - # Create a new callcontext for providing index as an argument. - new_context.callcontext = contextmod.CallContext(args=[index]) - - method = next(self.igetattr("__getitem__", context=context), None) - if not isinstance(method, bases.BoundMethod): - raise exceptions.InferenceError( - "Could not find __getitem__ for {node!r}.", node=self, context=context - ) - - return next(method.infer_call_result(self, new_context)) - - -bases.Instance.getitem = instance_getitem - - -def _populate_context_lookup(call, context): - # Allows context to be saved for later - # for inference inside a function - context_lookup = {} - if context is None: - return context_lookup - for arg in call.args: - if isinstance(arg, nodes.Starred): - context_lookup[arg.value] = context - else: - context_lookup[arg] = context - keywords = call.keywords if call.keywords is not None else [] - for keyword in keywords: - context_lookup[keyword.value] = context - return context_lookup - - -@decorators.raise_if_nothing_inferred -def infer_ifexp(self, context=None): - """Support IfExp inference - - If we can't infer the truthiness of the condition, we default - to inferring both branches. Otherwise, we infer either branch - depending on the condition. - """ - both_branches = False - # We use two separate contexts for evaluating lhs and rhs because - # evaluating lhs may leave some undesired entries in context.path - # which may not let us infer right value of rhs. - - context = context or contextmod.InferenceContext() - lhs_context = contextmod.copy_context(context) - rhs_context = contextmod.copy_context(context) - try: - test = next(self.test.infer(context=context.clone())) - except exceptions.InferenceError: - both_branches = True - else: - if test is not util.Uninferable: - if test.bool_value(): - yield from self.body.infer(context=lhs_context) - else: - yield from self.orelse.infer(context=rhs_context) - else: - both_branches = True - if both_branches: - yield from self.body.infer(context=lhs_context) - yield from self.orelse.infer(context=rhs_context) - - -nodes.IfExp._infer = infer_ifexp |