Merged in jaraco/six (pull request #12)

Add 'patch_with_metaclass' which provides a more complete interface for supporting metaclass-based classes across Python versions.

1 files changed, 63 insertions, 0 deletions

diff --git a/test_six.py b/test_six.py
index 38bd0e5..12d3a06 100644
--- a/test_six.py
+++ b/test_six.py
@@ -511,3 +511,66 @@ def test_with_metaclass():
     assert type(X) is Meta
     assert issubclass(X, Base)
     assert issubclass(X, Base2)
+
+
+def test_add_metaclass():
+    class Meta(type):
+        pass
+    class X:
+        "success"
+    X = six.add_metaclass(Meta)(X)
+    assert type(X) is Meta
+    assert issubclass(X, object)
+    assert X.__module__ is __name__
+    assert X.__doc__ == "success"
+    class Base(object):
+        pass
+    class X(Base):
+        pass
+    X = six.add_metaclass(Meta)(X)
+    assert type(X) is Meta
+    assert issubclass(X, Base)
+    class Base2(object):
+        pass
+    class X(Base, Base2):
+        pass
+    X = six.add_metaclass(Meta)(X)
+    assert type(X) is Meta
+    assert issubclass(X, Base)
+    assert issubclass(X, Base2)
+
+    # additionally test a second-generation subclass of a type
+    class Meta1(type):
+        m1 = "m1"
+    class Meta2(Meta1):
+        m2 = "m2"
+    class Base:
+        b = "b"
+    Base = six.add_metaclass(Meta1)(Base)
+    class X(Base):
+        x = "x"
+    X = six.add_metaclass(Meta2)(X)
+    assert type(X) is Meta2
+    assert issubclass(X, Base)
+    assert type(Base) is Meta1
+    assert "__dict__" not in vars(X)
+    instance = X()
+    instance.attr = "test"
+    assert vars(instance) == {"attr": "test"}
+    assert instance.b == Base.b
+    assert instance.x == X.x
+
+    # test a class with slots
+    class MySlots(object):
+        __slots__ = ["a", "b"]
+    MySlots = six.add_metaclass(Meta1)(MySlots)
+
+    assert MySlots.__slots__ == ["a", "b"]
+    instance = MySlots()
+    instance.a = "foo"
+    try:
+        instance.c = "baz"
+    except AttributeError:
+        pass
+    else:
+        raise RuntimeError("did not raise")