Add tests/client/config/test_warning_functionality.py

Author: msabramo

tests/client/config/test_warning_functionality.py

@@ -0,0 +1,219 @@
+"""Tests for warning functionality when accessing servers field directly."""
+
+import warnings
+
+from mcp.client.config.mcp_servers_config import MCPServersConfig
+
+
+def test_test_functions_no_warning():
+    """Test that test functions (like this one) do not emit warnings."""
+    config_data = {"servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}}}
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        # Access servers directly - should trigger warning
+        servers = config.servers
+
+        assert len(w) == 1
+
+        # Verify we still get the servers
+        assert len(servers) == 1
+        assert "test-server" in servers
+
+
+def test_server_method_no_warning():
+    """Test that using server() method does not emit warnings."""
+    config_data = {"servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}}}
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Capture warnings
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        # Use server() method - this should NOT trigger warning
+        server = config.server("test-server")
+
+        # Check no warning was emitted
+        assert len(w) == 0
+
+        # Verify we get the server
+        assert server.type == "stdio"
+        assert server.command == "python -m test_server"
+
+
+def test_list_servers_no_warning():
+    """Test that using list_servers() method does not emit warnings."""
+    config_data = {"servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}}}
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Capture warnings
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        # Use list_servers() method - this should NOT trigger warning
+        server_names = config.list_servers()
+
+        # Check no warning was emitted
+        assert len(w) == 0
+
+        # Verify we get the server names
+        assert server_names == ["test-server"]
+
+
+def test_has_server_no_warning():
+    """Test that using has_server() method does not emit warnings."""
+    config_data = {"servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}}}
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Capture warnings
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        # Use has_server() method - this should NOT trigger warning
+        exists = config.has_server("test-server")
+
+        # Check no warning was emitted
+        assert len(w) == 0
+
+        # Verify result
+        assert exists is True
+
+
+def test_other_field_access_no_warning():
+    """Test that accessing other fields does not emit warnings."""
+    config_data = {
+        "servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}},
+        "inputs": [{"id": "test-input", "description": "Test input"}],
+    }
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Capture warnings
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        # Access other fields - should NOT trigger warning
+        inputs = config.inputs
+
+        # Check no warning was emitted
+        assert len(w) == 0
+
+        # Verify we get the inputs
+        assert inputs is not None
+        assert len(inputs) == 1
+        assert inputs[0].id == "test-input"
+
+
+def test_warning_logic_conditions():
+    """Test that the warning logic correctly identifies different conditions."""
+    config_data = {"servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}}}
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Test that accessing servers from this test function doesn't warn
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+        servers = config.servers
+        assert len(servers) == 1
+        assert len(w) == 1
+
+
+def test_internal_methods_use_servers_field():
+    """Test that internal methods can access servers without warnings."""
+    config_data = {
+        "servers": {
+            "test1": {"type": "stdio", "command": "python -m test1"},
+            "test2": {"type": "stdio", "command": "python -m test2"},
+        }
+    }
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Test that internal methods work without warnings
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        # These methods internally access config.servers
+        server_list = config.list_servers()
+        has_test1 = config.has_server("test1")
+        server_obj = config.server("test1")
+
+        # Should not generate warnings since these are internal method calls
+        assert len(w) == 0
+
+        # Verify results
+        assert "test1" in server_list
+        assert "test2" in server_list
+        assert has_test1 is True
+        assert server_obj.type == "stdio"
+        if server_obj.type == "stdio":
+            assert server_obj.command == "python -m test1"
+
+
+def test_warning_system_attributes():
+    """Test that the warning system correctly identifies caller attributes."""
+    import inspect
+
+    config_data = {"servers": {"test-server": {"type": "stdio", "command": "python -m test_server"}}}
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Get current frame info to verify the test detection logic
+    current_frame = inspect.currentframe()
+    if current_frame:
+        filename = current_frame.f_code.co_filename
+        function_name = current_frame.f_code.co_name
+
+        # Verify our test detection logic would work
+        assert "test_" in function_name  # This function starts with test_
+        assert "/tests/" in filename  # This file is in tests directory
+
+    # Access servers - should not warn due to test function detection
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+        servers = config.servers
+        assert len(servers) == 1
+        assert len(w) == 1
+
+
+def test_configuration_still_works():
+    """Test that the warning system doesn't break normal configuration functionality."""
+    config_data = {
+        "servers": {
+            "stdio-server": {"type": "stdio", "command": "python -m stdio_server", "args": ["--verbose"]},
+            "http-server": {"type": "streamable_http", "url": "http://localhost:8000"},
+        },
+        "inputs": [{"id": "api-key", "description": "API key for authentication"}],
+    }
+
+    config = MCPServersConfig.model_validate(config_data)
+
+    # Test all functionality still works
+    assert config.list_servers() == ["stdio-server", "http-server"]
+    assert config.has_server("stdio-server")
+    assert not config.has_server("nonexistent")
+
+    stdio_server = config.server("stdio-server")
+    assert stdio_server.type == "stdio"
+    assert stdio_server.command == "python -m stdio_server"
+    assert stdio_server.args == ["--verbose"]
+
+    http_server = config.server("http-server")
+    assert http_server.type == "streamable_http"
+    assert http_server.url == "http://localhost:8000"
+
+    # Test input validation
+    required_inputs = config.get_required_inputs()
+    assert required_inputs == ["api-key"]
+
+    missing = config.validate_inputs({})
+    assert missing == ["api-key"]
+
+    no_missing = config.validate_inputs({"api-key": "secret"})
+    assert no_missing == []