File Content: brain_attrs.py # Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html # For details: https://github.com/PyCQA/astroid/blob/main/LICENSE # Copyright (c) https://github.com/PyCQA/astroid/blob/main/CONTRIBUTORS.txt """ Astroid hook for the attrs library Without this hook pylint reports unsupported-assignment-operation for attrs classes """ from astroid.helpers import safe_infer from astroid.manager import AstroidManager from astroid.nodes.node_classes import AnnAssign, Assign, AssignName, Call, Unknown from astroid.nodes.scoped_nodes import ClassDef ATTRIB_NAMES = frozenset( ("attr.ib", "attrib", "attr.attrib", "attr.field", "attrs.field", "field") ) ATTRS_NAMES = frozenset( ( "attr.s", "attrs", "attr.attrs", "attr.attributes", "attr.define", "attr.mutable", "attr.frozen", "attrs.define", "attrs.mutable", "attrs.frozen", ) ) def is_decorated_with_attrs(node, decorator_names=ATTRS_NAMES) -> bool: """Return whether a decorated node has an attr decorator applied.""" if not node.decorators: return False for decorator_attribute in node.decorators.nodes: if isinstance(decorator_attribute, Call): # decorator with arguments decorator_attribute = decorator_attribute.func if decorator_attribute.as_string() in decorator_names: return True inferred = safe_infer(decorator_attribute) if inferred and inferred.root().name == "attr._next_gen": return True return False def attr_attributes_transform(node: ClassDef) -> None: """Given that the ClassNode has an attr decorator, rewrite class attributes as instance attributes """ # Astroid can't infer this attribute properly # Prevents https://github.com/PyCQA/pylint/issues/1884 node.locals["__attrs_attrs__"] = [Unknown(parent=node)] for cdef_body_node in node.body: if not isinstance(cdef_body_node, (Assign, AnnAssign)): continue if isinstance(cdef_body_node.value, Call): if cdef_body_node.value.func.as_string() not in ATTRIB_NAMES: continue else: continue targets = ( cdef_body_node.targets if hasattr(cdef_body_node, "targets") else [cdef_body_node.target] ) for target in targets: rhs_node = Unknown( lineno=cdef_body_node.lineno, col_offset=cdef_body_node.col_offset, parent=cdef_body_node, ) if isinstance(target, AssignName): # Could be a subscript if the code analysed is # i = Optional[str] = "" # See https://github.com/PyCQA/pylint/issues/4439 node.locals[target.name] = [rhs_node] node.instance_attrs[target.name] = [rhs_node] AstroidManager().register_transform( ClassDef, attr_attributes_transform, is_decorated_with_attrs ) Submit