From 68a1a662e50e5fa3a671fee07c5a1ea7fd0c9889 Mon Sep 17 00:00:00 2001
From: Notime02 <94148329+Notime02@users.noreply.github.com>
Date: Fri, 19 Jun 2026 21:13:40 +0300
Subject: [PATCH] fix(#1): [$30 BOUNTY] [Python] Expand backend API contract
 edge-case

---
 tests/backend_api/test_api_contract.py | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 tests/backend_api/test_api_contract.py

diff --git a/tests/backend_api/test_api_contract.py b/tests/backend_api/test_api_contract.py
new file mode 100644
index 00000000..c0c491dc
--- /dev/null
+++ b/tests/backend_api/test_api_contract.py
@@ -0,0 +1,18 @@
+import pytest
+from backend.api_contract import APIContract
+
+@pytest.mark.parametrize("payload, expected_error", [
+    ({"missing_field": "value"}, "Missing required field: 'required_field'"),
+    ({"required_field": None}, "Invalid value for field: 'required_field'")
+])
+def test_api_contract_negative_cases(payload, expected_error):
+    with pytest.raises(APIContract.Error) as exc_info:
+        APIContract.validate(payload)
+    assert str(exc_info.value) == expected_error
+
+@pytest.mark.asyncio
+async def test_api_contract_async_wrapper():
+    async def async_helper():
+        return APIContract.validate({"required_field": "value"})
+    result = await async_helper()
+    assert result == {"required_field": "value"}