From 2deb5c758adc4a9a55dae93ecaad5af43c344591 Mon Sep 17 00:00:00 2001 From: Benjamin Peterson Date: Wed, 27 Jan 2010 02:16:42 +0000 Subject: raise a clear TypeError when trying to register a non-class --- Lib/abc.py | 2 +- Lib/test/test_abc.py | 6 ++++++ Misc/NEWS | 2 ++ 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/Lib/abc.py b/Lib/abc.py index 95126d8..8aeb2af 100644 --- a/Lib/abc.py +++ b/Lib/abc.py @@ -96,7 +96,7 @@ class ABCMeta(type): def register(cls, subclass): """Register a virtual subclass of an ABC.""" - if not isinstance(cls, type): + if not isinstance(subclass, type): raise TypeError("Can only register classes") if issubclass(subclass, cls): return # Already a subclass diff --git a/Lib/test/test_abc.py b/Lib/test/test_abc.py index 529f3e6..31f1986 100644 --- a/Lib/test/test_abc.py +++ b/Lib/test/test_abc.py @@ -149,6 +149,12 @@ class TestABC(unittest.TestCase): self.assertRaises(RuntimeError, C.register, A) # cycles not allowed C.register(B) # ok + def test_register_non_class(self): + class A(object): + __metaclass__ = abc.ABCMeta + self.assertRaisesRegexp(TypeError, "Can only register classes", + A.register, 4) + def test_registration_transitiveness(self): class A: __metaclass__ = abc.ABCMeta diff --git a/Misc/NEWS b/Misc/NEWS index 9ffd3e4..ac1295a 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -47,6 +47,8 @@ Core and Builtins Library ------- +- Issue #7792: Registering non-classes to ABCs raised an obscure error. + - Removed the functions 'verify' and 'vereq' from Lib/test/test_support.py. - Issue #7773: Fix an UnboundLocalError in platform.linux_distribution() when -- cgit v0.12