Rebase and add depreciation message

Author: mroeschke

doc/source/whatsnew/v0.23.0.txt

@@ -202,6 +202,8 @@ Other Enhancements
 - ``Resampler`` objects now have a functioning :attr:`~pandas.core.resample.Resampler.pipe` method.
   Previously, calls to ``pipe`` were diverted to  the ``mean`` method (:issue:`17905`).
 - :func:`~pandas.api.types.is_scalar` now returns ``True`` for ``DateOffset`` objects (:issue:`18943`).
+- :meth:`Timestamp.month_name`, :meth:`DatetimeIndex.month_name`, and :meth:`Series.dt.month_name` are now available (:issue:`12805`)
+- :meth:`Timestamp.day_name` and :meth:`DatetimeIndex.day_name` are now available to return day names with a specified locale (:issue:`12806`)
 
 .. _whatsnew_0230.api_breaking:
 

pandas/_libs/tslibs/timestamps.pyx

@@ -1,6 +1,9 @@
 # -*- coding: utf-8 -*-
 # cython: profile=False
 import warnings
+import locale
+
+from pandas.util.testing import set_locale
 
 from cpython cimport (PyObject_RichCompareBool, PyObject_RichCompare,
                       Py_GT, Py_GE, Py_EQ, Py_NE, Py_LT, Py_LE)
@@ -34,6 +37,7 @@ from np_datetime cimport (reverse_ops, cmp_scalar, check_dts_bounds,
 from timedeltas import Timedelta
 from timedeltas cimport delta_to_nanoseconds
 from timezones cimport get_timezone, is_utc, maybe_get_tz, treat_tz_as_pytz
+from strptime import LocaleTime
 
 # ----------------------------------------------------------------------
 # Constants
@@ -685,8 +689,59 @@ class Timestamp(_Timestamp):
     def dayofweek(self):
         return self.weekday()
 
+    def day_name(self, time_locale=None):
+        """
+        Return the day name of the Timestamp with specified locale.
+
+        Parameters
+        ----------
+        time_locale : string, default None (English locale)
+            locale determining the language in which to return the day name
+
+        Returns
+        -------
+        day_name : string
+        """
+        if time_locale is None:
+            days = {0: 'monday', 1: 'tuesday', 2: 'wednesday',
+                    3: 'thursday', 4: 'friday', 5: 'saturday',
+                    6: 'sunday'}
+        else:
+            with set_locale(time_locale, locale.LC_TIME):
+                locale_time = LocaleTime()
+                days = dict(enumerate(locale_time.f_weekday))
+        return days[self.weekday()].capitalize()
+
+    def month_name(self, time_locale=None):
+        """
+        Return the month name of the Timestamp with specified locale.
+
+        Parameters
+        ----------
+        time_locale : string, default None (English locale)
+            locale determining the language in which to return the month name
+
+        Returns
+        -------
+        month_name : string
+        """
+        if time_locale is None:
+            months = {1: 'january', 2: 'february', 3: 'march',
+                      4: 'april', 5: 'may', 6: 'june', 7: 'july',
+                      8: 'august', 9: 'september', 10: 'october',
+                      11: 'november', 12: 'december'}
+        else:
+            with set_locale(time_locale, locale.LC_TIME):
+                locale_time = LocaleTime()
+                months = dict(enumerate(locale_time.f_month))
+        return months[self.month].capitalize()
+
     @property
     def weekday_name(self):
+        """
+        .. depreciated:: 0.23.0
+            Use ``Timestamp.day_name()`` instead
+        """
         cdef dict wdays = {0: 'Monday', 1: 'Tuesday', 2: 'Wednesday',
                            3: 'Thursday', 4: 'Friday', 5: 'Saturday',
                            6: 'Sunday'}

pandas/core/indexes/datetimes.py

@@ -1688,7 +1688,7 @@ def freq(self, value):
     weekday_name = _field_accessor(
         'weekday_name',
         'weekday_name',
-        "The name of day in a week (ex: Friday)\n\n.. versionadded:: 0.18.1")
+        "The name of day in a week (ex: Friday)\n\n.. depreciated:: 0.23.0")
 
     dayofyear = _field_accessor('dayofyear', 'doy',
                                 "The ordinal day of the year")