gh-104683: Argument clinic: cleanup `state_modulename_name()` (#107340)

1 files changed, 26 insertions, 0 deletions

diff --git a/Lib/test/test_clinic.py b/Lib/test/test_clinic.py
index d1c61b1..d21c7d8 100644
--- a/Lib/test/test_clinic.py
+++ b/Lib/test/test_clinic.py
@@ -679,6 +679,32 @@ class ClinicParserTest(_ParserBase):
         """)
         self.assertIsInstance(function.return_converter, clinic.int_return_converter)
 
+    def test_return_converter_invalid_syntax(self):
+        stdout = self.parse_function_should_fail("""
+            module os
+            os.stat -> invalid syntax
+        """)
+        expected_error = "Badly formed annotation for os.stat: 'invalid syntax'"
+        self.assertIn(expected_error, stdout)
+
+    def test_legacy_converter_disallowed_in_return_annotation(self):
+        stdout = self.parse_function_should_fail("""
+            module os
+            os.stat -> "s"
+        """)
+        expected_error = "Legacy converter 's' not allowed as a return converter"
+        self.assertIn(expected_error, stdout)
+
+    def test_unknown_return_converter(self):
+        stdout = self.parse_function_should_fail("""
+            module os
+            os.stat -> foooooooooooooooooooooooo
+        """)
+        expected_error = (
+            "No available return converter called 'foooooooooooooooooooooooo'"
+        )
+        self.assertIn(expected_error, stdout)
+
     def test_star(self):
         function = self.parse_function("""
             module os