Fixed #15811 - lazy() doesn't take into account methods defined in parents

Thanks to abki for the report and patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16157 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/utils/functional.py

@@ -68,14 +68,15 @@ def lazy(func, *resultclasses):
             cls.__dispatch = {}
             for resultclass in resultclasses:
                 cls.__dispatch[resultclass] = {}
-                for (k, v) in resultclass.__dict__.items():
-                    # All __promise__ return the same wrapper method, but they
-                    # also do setup, inserting the method into the dispatch
-                    # dict.
-                    meth = cls.__promise__(resultclass, k, v)
-                    if hasattr(cls, k):
-                        continue
-                    setattr(cls, k, meth)
+                for type_ in reversed(resultclass.mro()):
+                    for (k, v) in type_.__dict__.items():
+                        # All __promise__ return the same wrapper method, but they
+                        # also do setup, inserting the method into the dispatch
+                        # dict.
+                        meth = cls.__promise__(resultclass, k, v)
+                        if hasattr(cls, k):
+                            continue
+                        setattr(cls, k, meth)
             cls._delegate_str = str in resultclasses
             cls._delegate_unicode = unicode in resultclasses
             assert not (cls._delegate_str and cls._delegate_unicode), "Cannot call lazy() with both str and unicode return types."

tests/regressiontests/utils/functional.py

@@ -7,3 +7,16 @@ class FunctionalTestCase(unittest.TestCase):
         t = lazy(lambda: tuple(range(3)), list, tuple)
         for a, b in zip(t(), range(3)):
             self.assertEqual(a, b)
+
+    def test_lazy_base_class(self):
+        """Test that lazy also finds base class methods in the proxy object"""
+
+        class Base(object):
+            def base_method(self):
+                pass
+
+        class Klazz(Base):
+            pass
+
+        t = lazy(lambda: Klazz(), Klazz)()
+        self.assertTrue('base_method' in dir(t))