test: cover unknown method return expressions

tests/test_validate_typecheck_diagnostics.py

@@ -87,6 +87,16 @@ class ValidateTypecheckDiagnosticsTests(unittest.TestCase):
         self.assertIn("tests/typecheck_method_return_expression_bad.claro", MODULE.EXPECTED)
         self.assertIn("tests/typecheck_method_return_expression_good.claro", MODULE.EXPECTED_OK)
 
+    def test_includes_unknown_method_return_expression_fixtures(self):
+        self.assertIn(
+            "tests/typecheck_method_unknown_return_expression_bad.claro",
+            MODULE.EXPECTED,
+        )
+        self.assertIn(
+            "tests/typecheck_method_unknown_return_expression_good.claro",
+            MODULE.EXPECTED_OK,
+        )
+
     def test_includes_method_field_return_diagnostic_fixture(self):
         self.assertIn("tests/typecheck_method_field_return_bad.claro", MODULE.EXPECTED)
         self.assertIn("tests/typecheck_method_field_return_good.claro", MODULE.EXPECTED_OK)

tests/typecheck_method_unknown_return_expression_bad.claro

@@ -0,0 +1,6 @@
+CLASS Player
+    TEACH square amount RETURNS NUMBER
+        CHECK TYPE amount IS NUMBER
+        RETURN missing
+    END
+END

tests/typecheck_method_unknown_return_expression_good.claro

@@ -0,0 +1,6 @@
+CLASS Player
+    TEACH square amount RETURNS NUMBER
+        CHECK TYPE amount IS NUMBER
+        RETURN amount
+    END
+END