BUG: Holiday(..) with both offset and observance raises NotImplementedError

GH10217

Author: bwillers

pandas/tests/test_tseries.py

@@ -737,6 +737,17 @@ def test_get_period_field_raises_on_out_of_range(self):
     def test_get_period_field_array_raises_on_out_of_range(self):
         self.assertRaises(ValueError, period.get_period_field_arr, -1, np.empty(1), 0)
 
+
+class TestHolidayConflictingArguments(tm.TestCase):
+
+    def test_both_offset_observance_raises(self):
+        from pandas.tseries.holiday import Holiday, SA, next_monday
+        from pandas import DateOffset
+
+        with self.assertRaises(NotImplementedError) as cm:
+            h = Holiday("Cyber Monday", month=11, day=1,
+                        offset=[DateOffset(weekday=SA(4))], observance=next_monday)
+
 if __name__ == '__main__':
     import nose
     nose.runmodule(argv=[__file__, '-vvs', '-x', '--pdb', '--pdb-failure'],

pandas/tseries/holiday.py

@@ -148,6 +148,9 @@ class from pandas.tseries.offsets
         >>> July3rd = Holiday('July 3rd', month=7, day=3,
                               days_of_week=(0, 1, 2, 3))
         """
+        if offset is not None and observance is not None:
+            raise NotImplementedError("Cannot use both offset and observance.")
+
         self.name = name
         self.year = year
         self.month = month