address review missed files

pandas/_libs/tslibs/timestamps.pyx

@@ -21,11 +21,10 @@ from util cimport (is_datetime64_object, is_timedelta64_object,
                    INT64_MAX)
 
 cimport ccalendar
-from ccalendar import get_locale_names, MONTHS_FULL, DAYS_FULL
 from conversion import tz_localize_to_utc, date_normalize
 from conversion cimport (tz_convert_single, _TSObject,
                          convert_to_tsobject, convert_datetime_to_tsobject)
-from fields import get_date_field, get_start_end_field
+from fields import get_start_end_field, get_date_name_field
 from nattype import NaT
 from nattype cimport NPY_NAT
 from np_datetime import OutOfBoundsDatetime
@@ -352,6 +351,16 @@ cdef class _Timestamp(datetime):
                                   field, freqstr, month_kw)
         return out[0]
 
+    cpdef _get_date_name_field(self, object field, object locale):
+        cdef:
+            int64_t val
+            ndarray out
+
+        val = self._maybe_convert_value_to_local()
+        out = get_date_name_field(np.array([val], dtype=np.int64),
+                                  field, locale=locale)
+        return out[0]
+
     @property
     def _repr_base(self):
         return '{date} {time}'.format(date=self._date_repr,
@@ -702,45 +711,39 @@ class Timestamp(_Timestamp):
     def dayofweek(self):
         return self.weekday()
 
-    def day_name(self, time_locale=None):
+    def day_name(self, locale=None):
         """
         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
         """
-        if time_locale is None:
-            names = DAYS_FULL
-        else:
-            names = get_locale_names('f_weekday', time_locale)
-        days = dict(enumerate(names))
-        return days[self.weekday()].capitalize()
+        return self._get_date_name_field('day_name', locale)
 
-    def month_name(self, time_locale=None):
+    def month_name(self, locale=None):
         """
         Return the month 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 month name
 
         Returns
         -------
         month_name : string
+
+        .. versionadded:: 0.23.0
         """
-        if time_locale is None:
-            names = MONTHS_FULL
-        else:
-            names = get_locale_names('f_month', time_locale)
-        months = dict(enumerate(names))
-        return months[self.month].capitalize()
+        return self._get_date_name_field('month_name', locale)
 
     @property
     def weekday_name(self):

pandas/tests/indexes/datetimes/test_misc.py

@@ -245,7 +245,10 @@ def test_datetimeindex_accessors(self):
     @pytest.mark.skipif(not tm.get_locales(), reason='No available locales')
     @pytest.mark.parametrize('time_locale', tm.get_locales() + [None])
     def test_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',
@@ -264,23 +267,27 @@ def test_datetime_name_accessors(self, time_locale):
         for day, name, eng_name in zip(range(4, 11),
                                        expected_days,
                                        english_days):
-            # Test Monday -> Sunday
             name = name.capitalize()
             assert dti.weekday_name[day] == eng_name
-            assert dti.day_name(time_locale=time_locale)[day] == name
+            assert dti.day_name(locale=time_locale)[day] == name
             ts = Timestamp(datetime(2016, 4, day))
             assert ts.weekday_name == eng_name
-            assert ts.day_name(time_locale=time_locale) == name
+            assert ts.day_name(locale=time_locale) == name
+        dti = dti.append(DatetimeIndex([pd.NaT]))
+        assert np.isnan(dti.day_name(locale=time_locale)[-1])
+        ts = Timestamp(pd.NaT)
+        assert np.isnan(ts.day_name(locale=time_locale))
 
         # GH 12805
         dti = DatetimeIndex(freq='M', start='2012', end='2013')
-        # Test January -> December
-        result = dti.month_name(time_locale=time_locale)
+        result = dti.month_name(locale=time_locale)
         expected = Index([month.capitalize() for month in expected_months])
         tm.assert_index_equal(result, expected)
         for date, expected in zip(dti, expected_months):
-            result = date.month_name(time_locale=time_locale)
+            result = date.month_name(locale=time_locale)
             assert result == expected.capitalize()
+        dti = dti.append(DatetimeIndex([pd.NaT]))
+        assert np.isnan(dti.month_name(locale=time_locale)[-1])
 
     def test_nanosecond_field(self):
         dti = DatetimeIndex(np.arange(10))