Fixed #19151 -- Added missing methods to EmptyQuerySet.

Added values() and values_list() methods to EmptyQuerySet.

django/db/models/query.py

@@ -1271,6 +1271,18 @@ class EmptyQuerySet(QuerySet):
             kwargs[arg.default_alias] = arg
         return dict([(key, None) for key in kwargs])
 
+    def values(self, *fields):
+        """
+        Always returns EmptyQuerySet.
+        """
+        return self
+
+    def values_list(self, *fields, **kwargs):
+        """
+        Always returns EmptyQuerySet.
+        """
+        return self
+
     # EmptyQuerySet is always an empty result in where-clauses (and similar
     # situations).
     value_annotation = False

tests/regressiontests/queries/tests.py

@@ -1698,6 +1698,13 @@ class EmptyQuerySetTests(TestCase):
             []
         )
 
+    def test_ticket_19151(self):
+        # #19151 -- Calling .values() or .values_list() on an EmptyQuerySet
+        # should return EmptyQuerySet and not cause an error.
+        q = EmptyQuerySet()
+        self.assertQuerysetEqual(q.values(), [])
+        self.assertQuerysetEqual(q.values_list(), [])
+
 
 class ValuesQuerysetTests(BaseQuerysetTest):
     def test_flat_values_lits(self):