BUG: tz aware Timestamp field accessors returns local values (#13303)

Add whatsnew

Author: mroeschke

doc/source/whatsnew/v0.20.0.txt

@@ -796,6 +796,7 @@ Bug Fixes
 ~~~~~~~~~
 
 - Bug in ``Timestamp.replace`` now raises ``TypeError`` when incorrect argument names are given; previously this raised ``ValueError`` (:issue:`15240`)
+- Bug in ``Timestamp`` returning UTC based time/date attributes when a timezone was provided (:issue:`13303`)
 - Bug in ``Index`` power operations with reversed operands (:issue:`14973`)
 - Bug in ``TimedeltaIndex`` addition where overflow was being allowed without error (:issue:`14816`)
 - Bug in ``TimedeltaIndex`` raising a ``ValueError`` when boolean indexing with ``loc`` (:issue:`14946`)

pandas/_libs/tslib.pyx

@@ -1233,7 +1233,10 @@ cdef class _Timestamp(datetime):
         return datetime.__sub__(self, other)
 
     cpdef _get_field(self, field):
-        out = get_date_field(np.array([self.value], dtype=np.int64), field)
+        val = self.value
+        if self.tz is not None and not _is_utc(self.tz):
+            val = tz_convert_single(self.value, 'UTC', self.tz)
+        out = get_date_field(np.array([val], dtype=np.int64), field)
         return int(out[0])
 
     cpdef _get_start_end_field(self, field):

pandas/tests/scalar/test_timestamp.py

@@ -550,6 +550,23 @@ def check(value, equal):
         check(ts.daysinmonth, 31)
         check(ts.daysinmonth, 31)
 
+        # GH 13303
+        ts = Timestamp('2014-12-31 23:59:00-05:00', tz='US/Eastern')
+        check(ts.year, 2014)
+        check(ts.month, 12)
+        check(ts.day, 31)
+        check(ts.hour, 23)
+        check(ts.minute, 59)
+        check(ts.second, 0)
+        self.assertRaises(AttributeError, lambda: ts.millisecond)
+        check(ts.microsecond, 0)
+        check(ts.nanosecond, 0)
+        check(ts.dayofweek, 2)
+        check(ts.quarter, 4)
+        check(ts.dayofyear, 365)
+        check(ts.week, 1)
+        check(ts.daysinmonth, 31)
+
     def test_nat_fields(self):
         # GH 10050
         ts = Timestamp('NaT')