name : eq_without_hash.py # Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html # For details: https://github.com/PyCQA/pylint/blob/main/LICENSE # Copyright (c) https://github.com/PyCQA/pylint/blob/main/CONTRIBUTORS.txt """This is the remnant of the python3 checker. It was removed because the transition from python 2 to python3 is behind us, but some checks are still useful in python3 after all. See https://github.com/PyCQA/pylint/issues/5025 """ from astroid import nodes from pylint import checkers, interfaces from pylint.checkers import utils from pylint.lint import PyLinter class EqWithoutHash(checkers.BaseChecker): name = "eq-without-hash" msgs = { "W1641": ( "Implementing __eq__ without also implementing __hash__", "eq-without-hash", "Used when a class implements __eq__ but not __hash__. Objects get " "None as their default __hash__ implementation if they also implement __eq__.", ), } @utils.only_required_for_messages("eq-without-hash") def visit_classdef(self, node: nodes.ClassDef) -> None: locals_and_methods = set(node.locals).union(x.name for x in node.mymethods()) if "__eq__" in locals_and_methods and "__hash__" not in locals_and_methods: self.add_message("eq-without-hash", node=node, confidence=interfaces.HIGH) def register(linter: PyLinter) -> None: linter.register_checker(EqWithoutHash(linter))