allow class.__module__ to be None

IPython/lib/pretty.py

@@ -638,10 +638,10 @@ def _re_pattern_pprint(obj, p, cycle):
 
 def _type_pprint(obj, p, cycle):
     """The pprint for classes and types."""
-    try:
-        mod = obj.__module__
-    except AttributeError:
-        # Heap allocated types might not have the module attribute.
+    mod = getattr(obj, '__module__', None)
+    if mod is None:
+        # Heap allocated types might not have the module attribute,
+        # and others may set it to None.
         return p.text(obj.__name__)
 
     if mod in ('__builtin__', 'exceptions'):

IPython/lib/tests/test_pretty.py

@@ -53,6 +53,11 @@ def _repr_pretty_(self, p, cycle):
 class Dummy2(Dummy1):
     _repr_pretty_ = None
 
+class NoModule(object):
+    pass
+
+NoModule.__module__ = None
+
 
 def test_indentation():
     """Test correct indentation in groups"""
@@ -106,3 +111,10 @@ def test_pprint_heap_allocated_type():
     import xxlimited
     output = pretty.pretty(xxlimited.Null)
     nt.assert_equal(output, 'xxlimited.Null')
+
+def test_pprint_nomod():
+    """
+    Test that pprint works for classes with no __module__.
+    """
+    output = pretty.pretty(NoModule)
+    nt.assert_equal(output, 'NoModule')