Add ergonomic Client class for testing MCP servers (#1870)

tests/test_examples.py

@@ -12,18 +12,16 @@ import pytest
 from pydantic import AnyUrl
 from pytest_examples import CodeExample, EvalExample, find_examples
 
-from examples.fastmcp.complex_inputs import mcp as complex_inputs_mcp
-from examples.fastmcp.desktop import mcp as desktop_mcp
-from examples.fastmcp.direct_call_tool_result_return import mcp as direct_call_tool_result_mcp
-from examples.fastmcp.simple_echo import mcp as simple_echo_mcp
-from mcp.shared.memory import create_connected_server_and_client_session as client_session
+from mcp import Client
 from mcp.types import TextContent, TextResourceContents
 
 
 @pytest.mark.anyio
 async def test_simple_echo():
     """Test the simple echo server"""
-    async with client_session(simple_echo_mcp._mcp_server) as client:
+    from examples.fastmcp.simple_echo import mcp
+
+    async with Client(mcp) as client:
         result = await client.call_tool("echo", {"text": "hello"})
         assert len(result.content) == 1
         content = result.content[0]
@@ -34,7 +32,9 @@ async def test_simple_echo():
 @pytest.mark.anyio
 async def test_complex_inputs():
     """Test the complex inputs server"""
-    async with client_session(complex_inputs_mcp._mcp_server) as client:
+    from examples.fastmcp.complex_inputs import mcp
+
+    async with Client(mcp) as client:
         tank = {"shrimp": [{"name": "bob"}, {"name": "alice"}]}
         result = await client.call_tool("name_shrimp", {"tank": tank, "extra_names": ["charlie"]})
         assert len(result.content) == 3
@@ -49,7 +49,9 @@ async def test_complex_inputs():
 @pytest.mark.anyio
 async def test_direct_call_tool_result_return():
     """Test the CallToolResult echo server"""
-    async with client_session(direct_call_tool_result_mcp._mcp_server) as client:
+    from examples.fastmcp.direct_call_tool_result_return import mcp
+
+    async with Client(mcp) as client:
         result = await client.call_tool("echo", {"text": "hello"})
         assert len(result.content) == 1
         content = result.content[0]
@@ -69,7 +71,9 @@ async def test_desktop(monkeypatch: pytest.MonkeyPatch):
     monkeypatch.setattr(Path, "iterdir", lambda self: mock_files)  # type: ignore[reportUnknownArgumentType]
     monkeypatch.setattr(Path, "home", lambda: Path("/fake/home"))
 
-    async with client_session(desktop_mcp._mcp_server) as client:
+    from examples.fastmcp.desktop import mcp
+
+    async with Client(mcp) as client:
         # Test the sum function
         result = await client.call_tool("sum", {"a": 1, "b": 2})
         assert len(result.content) == 1