[bugfix] TIMESTAMP not detected as date (apache#5629)

* [bugfix] TIMESTAMP not detected as date

* minor tweak

superset/dataframe.py

@@ -134,8 +134,12 @@ def datetime_conversion_rate(cls, data_series):
 
     @classmethod
     def is_date(cls, dtype):
-        if dtype.name:
-            return dtype.name.startswith('datetime')
+        if dtype and dtype.name:
+            return any([
+                dtype.name.lower().startswith(s)
+                for s in ['date', 'time']
+            ])
+        return False
 
     @classmethod
     def is_dimension(cls, dtype, column_name):

tests/dataframe_test.py

@@ -4,6 +4,8 @@
 from __future__ import print_function
 from __future__ import unicode_literals
 
+import numpy as np
+
 from superset.dataframe import dedup, SupersetDataFrame
 from superset.db_engine_specs import BaseEngineSpec
 from .base_tests import SupersetTestCase
@@ -118,6 +120,13 @@ def test_get_columns_type_inference(self):
             ],
         )
 
+    def test_is_date(self):
+        f = SupersetDataFrame.is_date
+        self.assertEquals(f(np.dtype('M')), True)
+
+        self.assertEquals(f(None), False)
+        self.assertEquals(f(np.dtype(np.int32)), False)
+
     def test_dedup_with_data(self):
         data = [
             ('a', 1),