def _broken_callable_location(self,
node: nodes.Name | nodes.Attribute) -> bool:
"""Check if node would be a broken location for collections.abc.Callable."""
if (in_type_checking_block(node)
or is_postponed_evaluation_enabled(node)
and is_node_in_type_annotation_context(node)):
return False
# Check first Callable arg is a list of arguments -> Callable[[int], None]
if not (isinstance(node.parent, nodes.Subscript)
and isinstance(node.parent.slice, nodes.Tuple)
and len(node.parent.slice.elts) == 2
and isinstance(node.parent.slice.elts[0], nodes.List)):
return False
# Check nested inside Optional or Union
parent_subscript = node.parent.parent
if isinstance(parent_subscript, nodes.BaseContainer):
parent_subscript = parent_subscript.parent
if not (isinstance(parent_subscript, nodes.Subscript)
and isinstance(parent_subscript.value,
(nodes.Name, nodes.Attribute))):
return False
inferred_parent = safe_infer(parent_subscript.value)
if not (isinstance(inferred_parent, nodes.FunctionDef) and
inferred_parent.qname() in {"typing.Optional", "typing.Union"}
or isinstance(inferred_parent, astroid.bases.Instance)
and inferred_parent.qname() == "typing._SpecialForm"):
return False
return True
def _check_for_alternative_union_syntax(
self,
node: nodes.Name | nodes.Attribute,
name: str,
) -> None:
"""Check if alternative union syntax could be used.
Requires
- Python 3.10
- OR: Python 3.7+ with postponed evaluation in
a type annotation context
"""
inferred = safe_infer(node)
if not (isinstance(inferred, nodes.FunctionDef)
and inferred.qname() in {"typing.Optional", "typing.Union"}
or isinstance(inferred, astroid.bases.Instance)
and inferred.qname() == "typing._SpecialForm"):
return
if not (self._py310_plus or is_node_in_type_annotation_context(node)):
return
self.add_message(
"consider-alternative-union-syntax",
node=node,
args=(name, self._msg_postponed_eval_hint(node)),
confidence=INFERENCE,
)
def _check_for_typing_alias(
self,
node: nodes.Name | nodes.Attribute,
) -> None:
"""Check if typing alias is deprecated or could be replaced.
Requires
- Python 3.9
- OR: Python 3.7+ with postponed evaluation in
a type annotation context
For Python 3.7+: Only emit message if change doesn't create
any name collisions, only ever used in a type annotation
context, and can safely be replaced.
"""
inferred = safe_infer(node)
if not isinstance(inferred, nodes.ClassDef):
return
alias = DEPRECATED_TYPING_ALIASES.get(inferred.qname(), None)
if alias is None:
return
if self._py39_plus:
if inferred.qname(
) == "typing.Callable" and self._broken_callable_location(node):
self._found_broken_callable_location = True
self._deprecated_typing_alias_msgs.append(
DeprecatedTypingAliasMsg(
node,
inferred.qname(),
alias.name,
))
return
# For PY37+, check for type annotation context first
if not is_node_in_type_annotation_context(node) and isinstance(
node.parent, nodes.Subscript):
if alias.name_collision is True:
self._alias_name_collisions.add(inferred.qname())
return
self._consider_using_alias_msgs.append(
DeprecatedTypingAliasMsg(
node,
inferred.qname(),
alias.name,
isinstance(node.parent, nodes.Subscript),
))
def _check_for_typing_alias(
self,
node: Union[astroid.Name, astroid.Attribute],
) -> None:
"""Check if typing alias is depecated or could be replaced.
Requires
- Python 3.9
- OR: Python 3.7+ with postponed evaluation in
a type annotation context
For Python 3.7+: Only emitt message if change doesn't create
any name collisions, only ever used in a type annotation
context, and can safely be replaced.
"""
inferred = safe_infer(node)
if not isinstance(inferred, astroid.ClassDef):
return
alias = DEPRECATED_TYPING_ALIASES.get(inferred.qname(), None)
if alias is None:
return
if self._py39_plus():
self.add_message(
"deprecated-typing-alias",
node=node,
args=(inferred.qname(), alias.name),
)
return
# For PY37+, check for type annotation context first
if not is_node_in_type_annotation_context(node) and isinstance(
node.parent, astroid.Subscript):
if alias.name_collision is True:
self._alias_name_collisions.add(inferred.qname())
return
self._consider_using_alias_msgs.append(
DeprecatedTypingAliasMsg(
node,
inferred.qname(),
alias.name,
isinstance(node.parent, astroid.Subscript),
))
def _check_broken_noreturn(self,
node: nodes.Name | nodes.Attribute) -> None:
"""Check for 'NoReturn' inside compound types."""
if not isinstance(node.parent, nodes.BaseContainer):
# NoReturn not part of a Union or Callable type
return
if (in_type_checking_block(node)
or is_postponed_evaluation_enabled(node)
and is_node_in_type_annotation_context(node)):
return
for inferred in node.infer():
# To deal with typing_extensions, don't use safe_infer
if (isinstance(inferred, (nodes.FunctionDef, nodes.ClassDef))
and inferred.qname() in TYPING_NORETURN
# In Python 3.7 - 3.8, NoReturn is alias of '_SpecialForm'
or isinstance(inferred, astroid.bases.BaseInstance)
and isinstance(inferred._proxied, nodes.ClassDef)
and inferred._proxied.qname() == "typing._SpecialForm"):
self.add_message("broken-noreturn",
node=node,
confidence=INFERENCE)
break
