# Copyright (c) 2006, 2008-2011, 2013-2014 LOGILAB S.A. (Paris, FRANCE) # Copyright (c) 2012-2014 Google, Inc. # Copyright (c) 2013-2018 Claudiu Popa # Copyright (c) 2014 Michal Nowikowski # Copyright (c) 2014 Brett Cannon # Copyright (c) 2014 Arun Persaud # Copyright (c) 2015 Ionel Cristian Maries # Copyright (c) 2016 Alexander Todorov # Copyright (c) 2016 Jakub Wilk # Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html # For details: https://github.com/PyCQA/pylint/blob/master/COPYING """check for new / old style related problems """ import astroid from pylint.checkers import BaseChecker from pylint.checkers.utils import check_messages, has_known_bases, node_frame_class from pylint.interfaces import IAstroidChecker MSGS = { "E1003": ( "Bad first argument %r given to super()", "bad-super-call", "Used when another argument than the current class is given as " "first argument of the super builtin.", ) } class NewStyleConflictChecker(BaseChecker): """checks for usage of new style capabilities on old style classes and other new/old styles conflicts problems * use of property, __slots__, super * "super" usage """ __implements__ = (IAstroidChecker,) # configuration section name name = "newstyle" # messages msgs = MSGS priority = -2 # configuration options options = () @check_messages("bad-super-call") def visit_functiondef(self, node): """check use of super""" # ignore actual functions or method within a new style class if not node.is_method(): return klass = node.parent.frame() for stmt in node.nodes_of_class(astroid.Call): if node_frame_class(stmt) != node_frame_class(node): # Don't look down in other scopes. continue expr = stmt.func if not isinstance(expr, astroid.Attribute): continue call = expr.expr # skip the test if using super if not ( isinstance(call, astroid.Call) and isinstance(call.func, astroid.Name) and call.func.name == "super" ): continue # super should not be used on an old style class if klass.newstyle or not has_known_bases(klass): # super first arg should not be the class if not call.args: continue # calling super(type(self), self) can lead to recursion loop # in derived classes arg0 = call.args[0] if ( isinstance(arg0, astroid.Call) and isinstance(arg0.func, astroid.Name) and arg0.func.name == "type" ): self.add_message("bad-super-call", node=call, args=("type",)) continue # calling super(self.__class__, self) can lead to recursion loop # in derived classes if ( len(call.args) >= 2 and isinstance(call.args[1], astroid.Name) and call.args[1].name == "self" and isinstance(arg0, astroid.Attribute) and arg0.attrname == "__class__" ): self.add_message( "bad-super-call", node=call, args=("self.__class__",) ) continue try: supcls = call.args and next(call.args[0].infer(), None) except astroid.InferenceError: continue if klass is not supcls: name = None # if supcls is not Uninferable, then supcls was inferred # and use its name. Otherwise, try to look # for call.args[0].name if supcls: name = supcls.name elif call.args and hasattr(call.args[0], "name"): name = call.args[0].name if name: self.add_message("bad-super-call", node=call, args=(name,)) visit_asyncfunctiondef = visit_functiondef def register(linter): """required method to auto register this checker """ linter.register_checker(NewStyleConflictChecker(linter))