#1574217: only swallow AttributeErrors in isinstance, not everything.
Patch and tests by Brian Harring, with improvements by Ralf Schmitt.
diff --git a/Lib/test/test_isinstance.py b/Lib/test/test_isinstance.py
index 9482e75..50920c5 100644
--- a/Lib/test/test_isinstance.py
+++ b/Lib/test/test_isinstance.py
@@ -81,6 +81,20 @@
self.assertRaises(TypeError, isinstance, I(), C())
+ # check that we don't mask non AttributeErrors
+ # see: http://bugs.python.org/issue1574217
+ def test_isinstance_dont_mask_non_attribute_error(self):
+ class C(object):
+ def getclass(self):
+ raise RuntimeError()
+ __class__=property(getclass)
+
+ c=C()
+ self.assertRaises(RuntimeError, isinstance, c, bool)
+
+ # test another code path
+ class D: pass
+ self.assertRaises(RuntimeError, isinstance, c, D)
# These tests are similar to above, but tickle certain code paths in