Show full Wikipedia 429 error message

test_api.py

@@ -0,0 +1,30 @@
+import unittest
+from unittest.mock import Mock, patch
+
+from simplejson.scanner import JSONDecodeError
+
+from add_links import api
+
+
+class ApiGetTests(unittest.TestCase):
+    def test_429_error_preserves_full_message(self) -> None:
+        response = Mock()
+        response.status_code = 429
+        response.text = (
+            "Too many requests. If you are a tool operator, contact "
+            "noc@example.org for help."
+        )
+        response.json.side_effect = JSONDecodeError("bad json", "", 0)
+
+        session = Mock()
+        session.get.return_value = response
+
+        with patch("add_links.api._get_active_session", return_value=session):
+            with self.assertRaises(api.MediawikiError) as ctx:
+                api.api_get({"action": "query"})
+
+        self.assertEqual(str(ctx.exception), response.text)
+
+
+if __name__ == "__main__":
+    unittest.main()