From 279fdf6b2c339ed1fc4e75e7ccafa9fa55ed7a72 Mon Sep 17 00:00:00 2001
From: sinhrks <sinhrks@gmail.com>
Date: Thu, 19 Jan 2017 08:29:51 +0900
Subject: [PATCH] remove import failure

---
 doc/source/whatsnew/v0.20.0.txt | 1 +
 pandas/core/internals.py        | 4 ++--
 pandas/types/cast.py            | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/doc/source/whatsnew/v0.20.0.txt b/doc/source/whatsnew/v0.20.0.txt
index 798151971363e..16efdbaf2bf76 100644
--- a/doc/source/whatsnew/v0.20.0.txt
+++ b/doc/source/whatsnew/v0.20.0.txt
@@ -384,6 +384,7 @@ Bug Fixes
 
 - Bug in ``pd.read_msgpack()`` in which ``Series`` categoricals were being improperly processed (:issue:`14901`)
 - Bug in ``Series.ffill()`` with mixed dtypes containing tz-aware datetimes. (:issue:`14956`)
+- Bug in ``.replace()`` may result in incorrect dtypes. (:issue:`12747`)
 
 
 
diff --git a/pandas/core/internals.py b/pandas/core/internals.py
index ff1357644ab8c..5c9b67e9c28ad 100644
--- a/pandas/core/internals.py
+++ b/pandas/core/internals.py
@@ -3236,7 +3236,7 @@ def comp(s):
             return _possibly_compare(values, getattr(s, 'asm8', s),
                                      operator.eq)
 
-        def _cast(block, scalar):
+        def _cast_scalar(block, scalar):
             dtype, val = _infer_dtype_from_scalar(scalar, pandas_dtype=True)
             if not is_dtype_equal(block.dtype, dtype):
                 dtype = _find_common_type([block.dtype, dtype])
@@ -3268,7 +3268,7 @@ def _cast(block, scalar):
                         # particular block
                         m = masks[i][b.mgr_locs.indexer]
                         if m.any():
-                            b, val = _cast(b, d)
+                            b, val = _cast_scalar(b, d)
                             new_rb.extend(b.putmask(m, val, inplace=True))
                         else:
                             new_rb.append(b)
diff --git a/pandas/types/cast.py b/pandas/types/cast.py
index 31fb9293e124a..cd3f3a2bf5a96 100644
--- a/pandas/types/cast.py
+++ b/pandas/types/cast.py
@@ -19,7 +19,7 @@
                      _ensure_int8, _ensure_int16,
                      _ensure_int32, _ensure_int64,
                      _NS_DTYPE, _TD_DTYPE, _INT64_DTYPE,
-                     _DATELIKE_DTYPES, _POSSIBLY_CAST_DTYPES)
+                     _POSSIBLY_CAST_DTYPES)
 from .dtypes import ExtensionDtype, DatetimeTZDtype, PeriodDtype
 from .generic import ABCDatetimeIndex, ABCPeriodIndex, ABCSeries
 from .missing import isnull, notnull