update registry test

Author: TomAugspurger

pandas/tests/dtypes/test_dtypes.py

@@ -788,12 +788,12 @@ def test_update_dtype_errors(self, bad_dtype):
 
 @pytest.mark.parametrize(
     'dtype',
-    [CategoricalDtype, IntervalDtype])
+    [CategoricalDtype, IntervalDtype, PeriodDtype])
 def test_registry(dtype):
     assert dtype in registry.dtypes
 
 
-@pytest.mark.parametrize('dtype', [DatetimeTZDtype, PeriodDtype])
+@pytest.mark.parametrize('dtype', [DatetimeTZDtype])
 def test_pandas_registry(dtype):
     assert dtype not in registry.dtypes
     assert dtype in _pandas_registry.dtypes
@@ -805,15 +805,15 @@ def test_pandas_registry(dtype):
      ('interval', IntervalDtype()),
      ('interval[int64]', IntervalDtype()),
      ('interval[datetime64[ns]]', IntervalDtype('datetime64[ns]')),
+     ('period[D]', PeriodDtype('D')),
      ('category', CategoricalDtype())])
 def test_registry_find(dtype, expected):
     assert registry.find(dtype) == expected
 
 
 @pytest.mark.parametrize(
     'dtype, expected',
-    [('period[D]', PeriodDtype('D')),
-     ('datetime64[ns, US/Eastern]', DatetimeTZDtype('ns', 'US/Eastern'))])
+    [('datetime64[ns, US/Eastern]', DatetimeTZDtype('ns', 'US/Eastern'))])
 def test_pandas_registry_find(dtype, expected):
     assert _pandas_registry.find(dtype) == expected