Add a helpful error message to let people know when they've specified named_parameters and forgotten to add names to their parameter tuples rather than crashing later with something obscure.

PiperOrigin-RevId: 280698220
Change-Id: I02cc1eecc3f3310acd0b5ad30f065d6aab240c9d

1 files changed, 22 insertions, 0 deletions

diff --git a/absl/testing/tests/parameterized_test.py b/absl/testing/tests/parameterized_test.py
index 4235675..85f8e9b 100755
--- a/absl/testing/tests/parameterized_test.py
+++ b/absl/testing/tests/parameterized_test.py
@@ -677,6 +677,28 @@ class ParameterizedTestsTest(absltest.TestCase):
         def test_mixed_something(self, unused_obj):
           pass
 
+  def test_named_test_with_no_name_fails(self):
+    with self.assertRaises(RuntimeError):
+
+      class _(parameterized.TestCase):
+
+        @parameterized.named_parameters(
+            (0,),
+        )
+        def test_something(self, unused_obj):
+          pass
+
+  def test_named_test_dict_with_no_name_fails(self):
+    with self.assertRaises(RuntimeError):
+
+      class _(parameterized.TestCase):
+
+        @parameterized.named_parameters(
+            {'unused_obj': 0},
+        )
+        def test_something(self, unused_obj):
+          pass
+
   def test_parameterized_test_iter_has_testcases_property(self):
     @parameterized.parameters(1, 2, 3, 4, 5, 6)
     def test_something(unused_self, unused_obj):  # pylint: disable=invalid-name