test: cover explicitly typed yesno object fields

tests/test_validate_typecheck_diagnostics.py

@@ -45,6 +45,12 @@ class ValidateTypecheckDiagnosticsTests(unittest.TestCase):
             MODULE.EXPECTED_OK,
         )
 
+    def test_includes_explicitly_typed_yesno_field_success_fixture(self):
+        self.assertIn(
+            "tests/typecheck_object_field_typed_yesno_good.claro",
+            MODULE.EXPECTED_OK,
+        )
+
     def test_includes_reverse_text_concatenation_success_fixture(self):
         self.assertIn(
             "tests/typecheck_object_field_text_concat_reverse_good.claro",

tests/typecheck_object_field_typed_yesno_good.claro

@@ -0,0 +1,7 @@
+CLASS Player
+    HAS ready YESNO
+END
+
+NEW Player player
+SET player.ready YESNO YES
+CHECK TYPE player.ready IS YESNO