address review

Author: mroeschke

pandas/_libs/tslibs/ccalendar.pyx

@@ -12,7 +12,7 @@ cimport numpy as cnp
 from numpy cimport int64_t, int32_t
 cnp.import_array()
 
-import locale
+from locale import LC_TIME
 from strptime import LocaleTime
 
 # ----------------------------------------------------------------------
@@ -210,7 +210,7 @@ cpdef int32_t get_day_of_year(int year, int month, int day) nogil:
     return day_of_year
 
 
-cpdef get_locale_names(object name_type, object time_locale=None):
+cpdef get_locale_names(object name_type, object locale=None):
     """Returns an array of localized day or month names
 
     Parameters
@@ -221,14 +221,10 @@ cpdef get_locale_names(object name_type, object time_locale=None):
 
     Returns
     -------
-    names : list
+    list of locale names
 
     """
-    cdef:
-        list locale_names
-
     from pandas.util.testing import set_locale
 
-    with set_locale(time_locale, locale.LC_TIME):
-        locale_names = getattr(LocaleTime(), name_type)
-    return locale_names
+    with set_locale(locale, LC_TIME):
+        return getattr(LocaleTime(), name_type)

pandas/_libs/tslibs/fields.pyx

@@ -86,25 +86,25 @@ def build_field_sarray(ndarray[int64_t] dtindex):
 @cython.wraparound(False)
 @cython.boundscheck(False)
 def get_date_name_field(ndarray[int64_t] dtindex, object field,
-                        object time_locale=None):
+                        object locale=None):
     """
     Given a int64-based datetime index, return array of strings of date
     name based on requested field (e.g. weekday_name)
     """
     cdef:
         Py_ssize_t i, count = 0
-        ndarray[object] out
+        ndarray[object] out, name
         pandas_datetimestruct dts
         int dow
 
     count = len(dtindex)
     out = np.empty(count, dtype=object)
 
     if field == 'day_name' or field == 'weekday_name':
-        if time_locale is None:
-            _dayname = np.array(DAYS_FULL, dtype=np.object_)
+        if locale is None:
+            names = np.array(DAYS_FULL, dtype=np.object_)
         else:
-            _dayname = np.array(get_locale_names('f_weekday', time_locale),
+            names = np.array(get_locale_names('f_weekday', locale),
                                 dtype=np.object_)
         for i in range(count):
             if dtindex[i] == NPY_NAT:
@@ -113,21 +113,21 @@ def get_date_name_field(ndarray[int64_t] dtindex, object field,
 
             dt64_to_dtstruct(dtindex[i], &dts)
             dow = dayofweek(dts.year, dts.month, dts.day)
-            out[i] = _dayname[dow].capitalize()
+            out[i] = names[dow].capitalize()
         return out
     elif field == 'month_name':
-        if time_locale is None:
-            _monthname = np.array(MONTHS_FULL, dtype=np.object_)
+        if locale is None:
+            names = np.array(MONTHS_FULL, dtype=np.object_)
         else:
-            _monthname = np.array(get_locale_names('f_month', time_locale),
+            names = np.array(get_locale_names('f_month', locale),
                                   dtype=np.object_)
         for i in range(count):
             if dtindex[i] == NPY_NAT:
                 out[i] = np.nan
                 continue
 
             dt64_to_dtstruct(dtindex[i], &dts)
-            out[i] = _monthname[dts.month].capitalize()
+            out[i] = names[dts.month].capitalize()
         return out
 
     raise ValueError("Field %s not supported" % field)

pandas/_libs/tslibs/nattype.pyx

@@ -320,25 +320,29 @@ class NaTType(_NaT):
 
         Parameters
         ----------
-        time_locale : string, default None (English locale)
+        locale : string, default None (English locale)
             locale determining the language in which to return the month name
 
         Returns
         -------
         month_name : string
+
+        .. versionadded:: 0.23.0
         """)
     day_name = _make_nan_func('day_name', # noqa:E128
         """
         Return the day name of the Timestamp with specified locale.
 
         Parameters
         ----------
-        time_locale : string, default None (English locale)
+        locale : string, default None (English locale)
             locale determining the language in which to return the day name
 
         Returns
         -------
         day_name : string
+
+        .. versionadded:: 0.23.0
         """)
     # _nat_methods
     date = _make_nat_func('date', datetime.date.__doc__)

pandas/core/indexes/datetimes.py

@@ -322,7 +322,7 @@ def _add_comparison_methods(cls):
     _datetimelike_methods = ['to_period', 'tz_localize',
                              'tz_convert',
                              'normalize', 'strftime', 'round', 'floor',
-                             'ceil']
+                             'ceil', 'month_name', 'day_name']
 
     _is_numeric_dtype = False
     _infer_as_myclass = True
@@ -2101,51 +2101,55 @@ def to_julian_date(self):
                              self.nanosecond / 3600.0 / 1e+9
                              ) / 24.0)
 
-    def month_name(self, time_locale=None):
+    def month_name(self, locale=None):
         """
         Return the month names of the DateTimeIndex with specified locale.
 
         Parameters
         ----------
-        time_locale : string, default None (English locale)
+        locale : string, default None (English locale)
             locale determining the language in which to return the month name
 
         Returns
         -------
         month_names : Index
             Index of month names
+
+        .. versionadded:: 0.23.0
         """
         values = self.asi8
         if self.tz is not None:
             if self.tz is not utc:
                 values = self._local_timestamps()
 
         result = fields.get_date_name_field(values, 'month_name',
-                                            time_locale=time_locale)
+                                            locale=locale)
         result = self._maybe_mask_results(result)
         return Index(result, name=self.name)
 
-    def day_name(self, time_locale=None):
+    def day_name(self, locale=None):
         """
         Return the day names of the DateTimeIndex with specified locale.
 
         Parameters
         ----------
-        time_locale : string, default None (English locale)
+        locale : string, default None (English locale)
             locale determining the language in which to return the day name
 
         Returns
         -------
         month_names : Index
             Index of day names
+
+        .. versionadded:: 0.23.0
         """
         values = self.asi8
         if self.tz is not None:
             if self.tz is not utc:
                 values = self._local_timestamps()
 
         result = fields.get_date_name_field(values, 'day_name',
-                                            time_locale=time_locale)
+                                            locale=locale)
         result = self._maybe_mask_results(result)
         return Index(result, name=self.name)
 

pandas/tests/scalar/timestamp/test_timestamp.py

@@ -22,7 +22,7 @@
 from pandas.errors import OutOfBoundsDatetime
 from pandas.compat import long, PY3
 from pandas.compat.numpy import np_datetime64_compat
-from pandas import Timestamp, Period, Timedelta
+from pandas import Timestamp, Period, Timedelta, NaT
 
 
 class TestTimestampProperties(object):
@@ -119,6 +119,11 @@ def test_names(self, data, time_locale):
         assert data.day_name(time_locale) == expected_day
         assert data.month_name(time_locale) == expected_month
 
+        # Test NaT
+        nan_ts = Timestamp(NaT)
+        assert np.isnan(nan_ts.day_name(time_locale))
+        assert np.isnan(nan_ts.month_name(time_locale))
+
     @pytest.mark.parametrize('tz', [None, 'UTC', 'US/Eastern', 'Asia/Tokyo'])
     def test_is_leap_year(self, tz):
         # GH 13727

pandas/tests/series/test_datetime_values.py

@@ -1,6 +1,8 @@
 # coding=utf-8
 # pylint: disable-msg=E1101,W0612
 
+import locale
+import calendar
 import pytest
 
 from datetime import datetime, date
@@ -32,7 +34,7 @@ def test_dt_namespace_accessor(self):
         ok_for_dt = DatetimeIndex._datetimelike_ops
         ok_for_dt_methods = ['to_period', 'to_pydatetime', 'tz_localize',
                              'tz_convert', 'normalize', 'strftime', 'round',
-                             'floor', 'ceil', 'weekday_name']
+                             'floor', 'ceil', 'day_name', 'month_name']
         ok_for_td = TimedeltaIndex._datetimelike_ops
         ok_for_td_methods = ['components', 'to_pytimedelta', 'total_seconds',
                              'round', 'floor', 'ceil']
@@ -274,6 +276,46 @@ def test_dt_accessor_no_new_attributes(self):
                                     "You cannot add any new attribute"):
             s.dt.xlabel = "a"
 
+    @pytest.mark.skipif(not tm.get_locales(), reason='No available locales')
+    @pytest.mark.parametrize('time_locale', tm.get_locales() + [None])
+    def test_dt_accessor_datetime_name_accessors(self, time_locale):
+        # Test Monday -> Sunday and January -> December, in that sequence
+        if time_locale is None:
+            # If the time_locale is None, day-name and month_name should
+            # return the english attributes
+            expected_days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday',
+                             'Friday', 'Saturday', 'Sunday']
+            expected_months = ['January', 'February', 'March', 'April', 'May',
+                               'June', 'July', 'August', 'September',
+                               'October', 'November', 'December']
+        else:
+            with tm.set_locale(time_locale, locale.LC_TIME):
+                expected_days = calendar.day_name[:]
+                expected_months = calendar.month_name[1:]
+
+        s = Series(DatetimeIndex(freq='D', start=datetime(1998, 1, 1),
+                                 periods=365))
+        english_days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday',
+                        'Friday', 'Saturday', 'Sunday']
+        for day, name, eng_name in zip(range(4, 11),
+                                       expected_days,
+                                       english_days):
+            name = name.capitalize()
+            assert s.dt.weekday_name[day] == eng_name
+            assert s.dt.day_name(locale=time_locale)[day] == name
+        s = s.append(Series([pd.NaT]))
+        assert np.isnan(s.dt.day_name(locale=time_locale).iloc[-1])
+
+        s = Series(DatetimeIndex(freq='M', start='2012', end='2013'))
+        result = s.dt.month_name(locale=time_locale)
+        expected = Series([month.capitalize() for month in expected_months])
+        tm.assert_series_equal(result, expected)
+        for s_date, expected in zip(s, expected_months):
+            result = s_date.month_name(locale=time_locale)
+            assert result == expected.capitalize()
+        s = s.append(Series([pd.NaT]))
+        assert np.isnan(s.dt.month_name(locale=time_locale).iloc[-1])
+
     def test_strftime(self):
         # GH 10086
         s = Series(date_range('20130101', periods=5))