Issue #2534: speed up isinstance() and issubclass() by 50-70%, so as to

match Python 2.5 speed despite the __instancecheck__ / __subclasscheck__
mechanism. In the process, fix a bug where isinstance() and issubclass(),
when given a tuple of classes as second argument, were looking up
__instancecheck__ / __subclasscheck__ on the tuple rather than on each
type object.

Reviewed by Benjamin Peterson and Raymond Hettinger.

1 files changed, 11 insertions, 5 deletions

diff --git a/Lib/test/test_exceptions.py b/Lib/test/test_exceptions.py
index c7de97c..b671cbc 100644
--- a/Lib/test/test_exceptions.py
+++ b/Lib/test/test_exceptions.py
@@ -582,12 +582,18 @@ class ExceptionTests(unittest.TestCase):
             except KeyError:
                 pass
             except:
-                self.fail("Should have raised TypeError")
+                self.fail("Should have raised KeyError")
             else:
-                self.fail("Should have raised TypeError")
-        self.assertEqual(stderr.getvalue(),
-                         "Exception ValueError: ValueError() "
-                         "in <class 'KeyError'> ignored\n")
+                self.fail("Should have raised KeyError")
+
+        def g():
+            try:
+                return g()
+            except RuntimeError:
+                return sys.exc_info()
+        e, v, tb = g()
+        self.assert_(isinstance(v, RuntimeError), type(v))
+        self.assert_("maximum recursion depth exceeded" in str(v), str(v))
 
 
     def test_MemoryError(self):