fix: pytest coroutine warnings (#227)

Root cause**: All three warnings came from tests of the `main()`
function, where `asyncio.run` was mocked but `run_proxy(args)` still
created coroutines that were never awaited:

1. **`test_main_default`** in `test_main.py` —
`@patch('mcp_proxy_for_aws.server.run_proxy')` auto-detected the async
function and created an `AsyncMock`. Calling it produced a coroutine
passed to the mocked `asyncio.run`, which never awaited it.

2. **`test_main_function`** in `test_server.py` — `run_proxy` wasn't
patched at all, so the real `async def run_proxy(args)` created a real
coroutine that the mocked `asyncio.run` discarded.

3. **`test_main_error_handling`** in `test_server.py` — Same issue as

**Fix**: Added `@patch('mcp_proxy_for_aws.server.run_proxy',
new_callable=Mock)` to all three tests. Using `new_callable=Mock` forces
a regular `Mock` instead of an `AsyncMock`, so calling
`mock_run_proxy(args)` returns a plain `MagicMock` (not a coroutine),
which is safely passed to the mocked `asyncio.run` without any unawaited
coroutine issues.

Author: arnewouters

tests/unit/test_main.py

@@ -15,20 +15,17 @@
 """Tests for the main function in server.py."""
 
 from mcp_proxy_for_aws.server import main
-from unittest.mock import AsyncMock, patch
+from unittest.mock import Mock, patch
 
 
 class TestMain:
     """Tests for the main function."""
 
     @patch('mcp_proxy_for_aws.server.asyncio.run')
-    @patch('mcp_proxy_for_aws.server.run_proxy')
+    @patch('mcp_proxy_for_aws.server.run_proxy', new_callable=Mock)
     @patch('sys.argv', ['mcp-proxy-for-aws', 'https://test.example.com'])
     def test_main_default(self, mock_run_proxy, mock_asyncio_run):
         """Test main function with default arguments."""
-        # Mock run_proxy as async
-        mock_run_proxy.return_value = AsyncMock()
-
         # Mock asyncio.run to avoid actual execution
         mock_asyncio_run.return_value = None
 

tests/unit/test_server.py

@@ -364,8 +364,9 @@ def test_parse_args_custom(self):
         assert args.retries == 5
 
     @patch('mcp_proxy_for_aws.server.asyncio.run')
+    @patch('mcp_proxy_for_aws.server.run_proxy', new_callable=Mock)
     @patch('sys.argv', ['test', 'https://test.example.com'])
-    def test_main_function(self, mock_asyncio_run):
+    def test_main_function(self, mock_run_proxy, mock_asyncio_run):
         """Test that main function runs server correctly."""
         # Arrange
         mock_asyncio_run.return_value = None
@@ -377,8 +378,9 @@ def test_main_function(self, mock_asyncio_run):
         mock_asyncio_run.assert_called_once()
 
     @patch('mcp_proxy_for_aws.server.asyncio.run')
+    @patch('mcp_proxy_for_aws.server.run_proxy', new_callable=Mock)
     @patch('sys.argv', ['test', 'https://test.example.com'])
-    def test_main_error_handling(self, mock_asyncio_run):
+    def test_main_error_handling(self, mock_run_proxy, mock_asyncio_run):
         """Test that main function handles errors gracefully."""
         # Arrange
         mock_asyncio_run.side_effect = Exception('Test error')