# 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 from astroid import nodes from pylint import interfaces from pylint.checkers import BaseChecker from pylint.checkers.utils import check_messages, safe_infer class ThreadingChecker(BaseChecker): """Checks for threading module - useless with lock - locking used in wrong way that has no effect (with threading.Lock():) """ __implements__ = interfaces.IAstroidChecker name = "threading" LOCKS = frozenset( ( "threading.Lock", "threading.RLock", "threading.Condition", "threading.Semaphore", "threading.BoundedSemaphore", ) ) msgs = { "W2101": ( "'%s()' directly created in 'with' has no effect", "useless-with-lock", "Used when a new lock instance is created by using with statement " "which has no effect. Instead, an existing instance should be used to acquire lock.", ), } @check_messages("useless-with-lock") def visit_with(self, node: nodes.With) -> None: context_managers = (c for c, _ in node.items if isinstance(c, nodes.Call)) for context_manager in context_managers: if isinstance(context_manager, nodes.Call): infered_function = safe_infer(context_manager.func) if infered_function is None: continue qname = infered_function.qname() if qname in self.LOCKS: self.add_message("useless-with-lock", node=node, args=qname) def register(linter): """required method to auto register this checker""" linter.register_checker(ThreadingChecker(linter))