From 7cf00a23105a709b8184ba221076654a93def73f Mon Sep 17 00:00:00 2001
From: tp <terji78@yaho.com>
Date: Tue, 11 Jul 2017 22:13:21 +0100
Subject: [PATCH 1/4] Make _get_dtype accept pd.Categorical and
 pd.CategoricalIndex instances

---
 pandas/core/dtypes/common.py       | 4 +++-
 pandas/tests/dtypes/test_common.py | 6 +++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 2eebf3704253e..59846c9f164d9 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -11,7 +11,7 @@
                      ExtensionDtype)
 from .generic import (ABCCategorical, ABCPeriodIndex,
                       ABCDatetimeIndex, ABCSeries,
-                      ABCSparseArray, ABCSparseSeries)
+                      ABCSparseArray, ABCSparseSeries, ABCCategoricalIndex)
 from .inference import is_string_like
 from .inference import *  # noqa
 
@@ -1713,6 +1713,8 @@ def _get_dtype(arr_or_dtype):
             return PeriodDtype.construct_from_string(arr_or_dtype)
         elif is_interval_dtype(arr_or_dtype):
             return IntervalDtype.construct_from_string(arr_or_dtype)
+    elif isinstance(arr_or_dtype, (ABCCategorical, ABCCategoricalIndex)):
+        return  arr_or_dtype.dtype
 
     if hasattr(arr_or_dtype, 'dtype'):
         arr_or_dtype = arr_or_dtype.dtype
diff --git a/pandas/tests/dtypes/test_common.py b/pandas/tests/dtypes/test_common.py
index c32e8590c5675..7188e397c0617 100644
--- a/pandas/tests/dtypes/test_common.py
+++ b/pandas/tests/dtypes/test_common.py
@@ -532,16 +532,16 @@ def test_is_complex_dtype():
     (float, np.dtype(float)),
     ('float64', np.dtype('float64')),
     (np.dtype('float64'), np.dtype('float64')),
-    pytest.mark.xfail((str, np.dtype('<U')), ),
+    (str, np.dtype(str)),
     (pd.Series([1, 2], dtype=np.dtype('int16')), np.dtype('int16')),
     (pd.Series(['a', 'b']), np.dtype(object)),
     (pd.Index([1, 2]), np.dtype('int64')),
     (pd.Index(['a', 'b']), np.dtype(object)),
     ('category', 'category'),
     (pd.Categorical(['a', 'b']).dtype, CategoricalDtype()),
-    pytest.mark.xfail((pd.Categorical(['a', 'b']), CategoricalDtype()),),
+    (pd.Categorical(['a', 'b']), CategoricalDtype()),
     (pd.CategoricalIndex(['a', 'b']).dtype, CategoricalDtype()),
-    pytest.mark.xfail((pd.CategoricalIndex(['a', 'b']), CategoricalDtype()),),
+    (pd.CategoricalIndex(['a', 'b']), CategoricalDtype()),
     (pd.DatetimeIndex([1, 2]), np.dtype('<M8[ns]')),
     (pd.DatetimeIndex([1, 2]).dtype, np.dtype('<M8[ns]')),
     ('<M8[ns]', np.dtype('<M8[ns]')),

From fb0fe34e398f09a4044665c767c0041749d7d1d7 Mon Sep 17 00:00:00 2001
From: tp <terji78@yaho.com>
Date: Tue, 11 Jul 2017 22:47:11 +0100
Subject: [PATCH 2/4] small flake8 cleanup

---
 pandas/core/dtypes/common.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/dtypes/common.py b/pandas/core/dtypes/common.py
index 59846c9f164d9..a386c04cc4fdd 100644
--- a/pandas/core/dtypes/common.py
+++ b/pandas/core/dtypes/common.py
@@ -1714,7 +1714,7 @@ def _get_dtype(arr_or_dtype):
         elif is_interval_dtype(arr_or_dtype):
             return IntervalDtype.construct_from_string(arr_or_dtype)
     elif isinstance(arr_or_dtype, (ABCCategorical, ABCCategoricalIndex)):
-        return  arr_or_dtype.dtype
+        return arr_or_dtype.dtype
 
     if hasattr(arr_or_dtype, 'dtype'):
         arr_or_dtype = arr_or_dtype.dtype

From 3b4ef99a92b82a9054146f6e858944d121110ab7 Mon Sep 17 00:00:00 2001
From: tp <terji78@yaho.com>
Date: Wed, 12 Jul 2017 22:18:43 +0100
Subject: [PATCH 3/4] Added a note for change in dtypes.common._get_dtype in
 whatsnew

---
 doc/source/whatsnew/v0.21.0.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v0.21.0.txt b/doc/source/whatsnew/v0.21.0.txt
index 015fdf1f45f47..4523569fb0f63 100644
--- a/doc/source/whatsnew/v0.21.0.txt
+++ b/doc/source/whatsnew/v0.21.0.txt
@@ -147,7 +147,8 @@ Bug Fixes
 Conversion
 ^^^^^^^^^^
 
-
+- :func:`dtypes.common._get_dtype` now accepts ``Categorical``s and
+  ``CategoricalIndex`` (:issue:`16887`).
 
 Indexing
 ^^^^^^^^

From 54da1458f45161f3c6215dbe4e53711bf73dca88 Mon Sep 17 00:00:00 2001
From: topper-123 <terji78@gmail.com>
Date: Thu, 13 Jul 2017 21:32:51 +0100
Subject: [PATCH 4/4] Removed entry in whatsnew

---
 doc/source/whatsnew/v0.21.0.txt | 2 --
 1 file changed, 2 deletions(-)

diff --git a/doc/source/whatsnew/v0.21.0.txt b/doc/source/whatsnew/v0.21.0.txt
index 4523569fb0f63..40df813cf4b3b 100644
--- a/doc/source/whatsnew/v0.21.0.txt
+++ b/doc/source/whatsnew/v0.21.0.txt
@@ -147,8 +147,6 @@ Bug Fixes
 Conversion
 ^^^^^^^^^^
 
-- :func:`dtypes.common._get_dtype` now accepts ``Categorical``s and
-  ``CategoricalIndex`` (:issue:`16887`).
 
 Indexing
 ^^^^^^^^