Merge pull request #289 from noamkush/support_issubclass

Add support for issubclass

freezegun/api.py

@@ -226,6 +226,10 @@ class FakeDateMeta(type):
     def __instancecheck__(self, obj):
         return isinstance(obj, real_date)
 
+    @classmethod
+    def __subclasscheck__(cls, subclass):
+        return issubclass(subclass, real_date)
+
 
 def datetime_to_fakedatetime(datetime):
     return FakeDatetime(datetime.year,
@@ -285,6 +289,10 @@ class FakeDatetimeMeta(FakeDateMeta):
     def __instancecheck__(self, obj):
         return isinstance(obj, real_datetime)
 
+    @classmethod
+    def __subclasscheck__(cls, subclass):
+        return issubclass(subclass, real_datetime)
+
 
 class FakeDatetime(with_metaclass(FakeDatetimeMeta, real_datetime, FakeDate)):
     def __new__(cls, *args, **kwargs):

tests/test_class_import.py

@@ -70,6 +70,17 @@ def test_isinstance_works():
     freezer.stop()
 
 
+def test_issubclass_works():
+    real_date = datetime.date
+    real_datetime = datetime.datetime
+
+    freezer = freeze_time('2011-01-01')
+    freezer.start()
+    assert issubclass(real_date, datetime.date)
+    assert issubclass(real_datetime, datetime.datetime)
+    freezer.stop()
+
+
 def test_fake_uses_real_when_ignored():
     real_time_before = time.time()
     with freeze_time('2012-01-14', ignore=['tests.fake_module']):