chore: import upstream snapshot with attribution

tests/docs_src/test_logging.py

@@ -0,0 +1,62 @@
+"""`docs/handlers/logging.md`: every claim the page makes, proved against the real SDK."""
+
+import logging
+
+import pytest
+from inline_snapshot import snapshot
+from mcp_types import CallToolResult, TextContent
+
+from docs_src.logging import tutorial001
+from mcp import Client
+from mcp.server import MCPServer
+
+# See test_index.py for why this is a per-module mark and not a conftest hook.
+pytestmark = [pytest.mark.anyio, pytest.mark.filterwarnings("error::mcp.MCPDeprecationWarning")]
+
+
+async def test_the_tool_logs_through_the_standard_library(caplog: pytest.LogCaptureFixture) -> None:
+    """tutorial001: `logger.info(...)` inside a tool emits an ordinary stdlib record named after the module."""
+    caplog.set_level(logging.INFO)
+    async with Client(tutorial001.mcp) as client:
+        await client.call_tool("search_books", {"query": "dune"})
+    (record,) = list(filter(lambda r: r.name == tutorial001.logger.name, caplog.records))
+    assert record.levelname == "INFO"
+    assert record.getMessage() == "Searching for 'dune'"
+
+
+async def test_the_log_line_never_reaches_the_client() -> None:
+    """tutorial001: the result is only the return value. Log output is invisible to the model."""
+    async with Client(tutorial001.mcp) as client:
+        result = await client.call_tool("search_books", {"query": "dune"})
+        assert result == snapshot(
+            CallToolResult(
+                content=[TextContent(type="text", text="Found 3 books matching 'dune'.")],
+                structured_content={"result": "Found 3 books matching 'dune'."},
+            )
+        )
+
+
+def test_log_level_configures_the_root_logger() -> None:
+    """`MCPServer(log_level=...)` calls `logging.basicConfig()` when nothing has configured logging yet."""
+    root = logging.getLogger()
+    handlers, level = root.handlers[:], root.level
+    root.handlers = []
+    try:
+        MCPServer("Bookshop", log_level="DEBUG")
+        assert root.level == logging.DEBUG
+        assert len(root.handlers) == 1
+    finally:
+        root.handlers, root.level = handlers, level
+
+
+def test_an_existing_logging_configuration_wins() -> None:
+    """`logging.basicConfig()` is a no-op once a handler is installed, so your own setup is not overridden."""
+    root = logging.getLogger()
+    handlers, level = root.handlers[:], root.level
+    root.handlers, root.level = [logging.NullHandler()], logging.WARNING
+    try:
+        MCPServer("Bookshop", log_level="DEBUG")
+        assert root.level == logging.WARNING
+        assert len(root.handlers) == 1
+    finally:
+        root.handlers, root.level = handlers, level