# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html
# For details: https://github.com/pylint-dev/astroid/blob/main/LICENSE
# Copyright (c) https://github.com/pylint-dev/astroid/blob/main/CONTRIBUTORS.txt
"""This module contains mixin classes for scoped nodes."""
from __future__ import annotations
from typing import TYPE_CHECKING, TypeVar, overload
from astroid.exceptions import ParentMissingError
from astroid.filter_statements import _filter_stmts
from astroid.nodes import _base_nodes, scoped_nodes
from astroid.nodes.scoped_nodes.utils import builtin_lookup
from astroid.typing import InferenceResult, SuccessfulInferenceResult
if TYPE_CHECKING:
from astroid import nodes
_T = TypeVar("_T")
[docs]
class LocalsDictNodeNG(_base_nodes.LookupMixIn):
"""this class provides locals handling common to Module, FunctionDef
and ClassDef nodes, including a dict like interface for direct access
to locals information
"""
# attributes below are set by the builder module or by raw factories
locals: dict[str, list[InferenceResult]]
"""A map of the name of a local variable to the node defining the local."""
[docs]
def qname(self) -> str:
"""Get the 'qualified' name of the node.
For example: module.name, module.class.name ...
:returns: The qualified name.
:rtype: str
"""
# pylint: disable=no-member; github.com/pylint-dev/astroid/issues/278
if self.parent is None:
return self.name
try:
return f"{self.parent.frame().qname()}.{self.name}"
except ParentMissingError:
return self.name
[docs]
def scope(self: _T) -> _T:
"""The first parent node defining a new scope.
:returns: The first parent scope node.
:rtype: Module or FunctionDef or ClassDef or Lambda or GenExpr
"""
return self
[docs]
def scope_lookup(
self, node: _base_nodes.LookupMixIn, name: str, offset: int = 0
) -> tuple[LocalsDictNodeNG, list[nodes.NodeNG]]:
"""Lookup where the given variable is assigned.
:param node: The node to look for assignments up to.
Any assignments after the given node are ignored.
:param name: The name of the variable to find assignments for.
:param offset: The line offset to filter statements up to.
:returns: This scope node and the list of assignments associated to the
given name according to the scope where it has been found (locals,
globals or builtin).
"""
raise NotImplementedError
def _scope_lookup(
self, node: _base_nodes.LookupMixIn, name: str, offset: int = 0
) -> tuple[LocalsDictNodeNG, list[nodes.NodeNG]]:
"""XXX method for interfacing the scope lookup"""
try:
stmts = _filter_stmts(node, self.locals[name], self, offset)
except KeyError:
stmts = ()
if stmts:
return self, stmts
# Handle nested scopes: since class names do not extend to nested
# scopes (e.g., methods), we find the next enclosing non-class scope
pscope = self.parent and self.parent.scope()
while pscope is not None:
if not isinstance(pscope, scoped_nodes.ClassDef):
return pscope.scope_lookup(node, name)
pscope = pscope.parent and pscope.parent.scope()
# self is at the top level of a module, or is enclosed only by ClassDefs
return builtin_lookup(name)
[docs]
def set_local(self, name: str, stmt: nodes.NodeNG) -> None:
"""Define that the given name is declared in the given statement node.
.. seealso:: :meth:`scope`
:param name: The name that is being defined.
:param stmt: The statement that defines the given name.
"""
# assert not stmt in self.locals.get(name, ()), (self, stmt)
self.locals.setdefault(name, []).append(stmt)
__setitem__ = set_local
def _append_node(self, child: nodes.NodeNG) -> None:
"""append a child, linking it in the tree"""
# pylint: disable=no-member; depending by the class
# which uses the current class as a mixin or base class.
# It's rewritten in 2.0, so it makes no sense for now
# to spend development time on it.
self.body.append(child) # type: ignore[attr-defined]
child.parent = self
@overload
def add_local_node(
self, child_node: nodes.ClassDef, name: str | None = ...
) -> None: ...
@overload
def add_local_node(self, child_node: nodes.NodeNG, name: str) -> None: ...
[docs]
def add_local_node(self, child_node: nodes.NodeNG, name: str | None = None) -> None:
"""Append a child that should alter the locals of this scope node.
:param child_node: The child node that will alter locals.
:param name: The name of the local that will be altered by
the given child node.
"""
if name != "__class__":
# add __class__ node as a child will cause infinite recursion later!
self._append_node(child_node)
self.set_local(name or child_node.name, child_node) # type: ignore[attr-defined]
def __getitem__(self, item: str) -> SuccessfulInferenceResult:
"""The first node the defines the given local.
:param item: The name of the locally defined object.
:raises KeyError: If the name is not defined.
"""
return self.locals[item][0]
def __iter__(self):
"""Iterate over the names of locals defined in this scoped node.
:returns: The names of the defined locals.
:rtype: iterable(str)
"""
return iter(self.keys())
[docs]
def keys(self):
"""The names of locals defined in this scoped node.
:returns: The names of the defined locals.
:rtype: list(str)
"""
return list(self.locals.keys())
[docs]
def values(self):
"""The nodes that define the locals in this scoped node.
:returns: The nodes that define locals.
:rtype: list(NodeNG)
"""
# pylint: disable=consider-using-dict-items
# It look like this class override items/keys/values,
# probably not worth the headache
return [self[key] for key in self.keys()]
[docs]
def items(self):
"""Get the names of the locals and the node that defines the local.
:returns: The names of locals and their associated node.
:rtype: list(tuple(str, NodeNG))
"""
return list(zip(self.keys(), self.values()))
def __contains__(self, name) -> bool:
"""Check if a local is defined in this scope.
:param name: The name of the local to check for.
:type name: str
:returns: Whether this node has a local of the given name,
"""
return name in self.locals
[docs]
class ComprehensionScope(LocalsDictNodeNG):
"""Scoping for different types of comprehensions."""
scope_lookup = LocalsDictNodeNG._scope_lookup
generators: list[nodes.Comprehension]
"""The generators that are looped through."""