debug

examples/servers/threaded_handlers.py

@@ -20,6 +20,7 @@
 """
 from __future__ import annotations
 
+import logging
 import time
 import threading
 
@@ -93,4 +94,5 @@ def count_down_error(ls: LanguageServer, *args):
 
 
 if __name__ == "__main__":
+    logging.basicConfig(level=logging.DEBUG)
     start_server(server)

pyproject.toml

@@ -67,7 +67,7 @@ poetry_lock_check = "poetry check"
 [tool.poe.tasks.test]
 sequence = [
      { cmd = "pytest --cov" },
-     { cmd = "pytest tests/e2e --lsp-transport tcp" },
+     { cmd = "pytest tests/e2e --lsp-transport tcp --log-cli-level debug -vs" },
 ]
 ignore_fail = "return_non_zero"
 

tests/conftest.py

@@ -189,6 +189,16 @@ def server_dir():
     return path.resolve()
 
 
+async def forward_stderr(server: asyncio.subprocess.Process):
+    if server.stderr is None:
+        return
+
+    # EOF is signalled with an empty bytestring
+    while (line := await server.stderr.readline()) != b"":
+        sys.stderr.buffer.write(line)
+
+
+
 def get_client_for_cpython_server(transport, uri_fixture):
     """Return a client configured to communicate with a server running under cpython."""
 
@@ -199,6 +209,7 @@ async def fn(
 
         server_cmd = [sys.executable, str(SERVER_DIR / server_name)]
         server: asyncio.subprocess.Process | None = None
+        stderr_forwarder = None
 
         if transport == "stdio":
             await client.start_io(*server_cmd)
@@ -208,7 +219,8 @@ async def fn(
             host, port = "localhost", 8888
             server_cmd.extend(["--tcp", "--host", host, "--port", f"{port}"])
 
-            server = await asyncio.create_subprocess_exec(*server_cmd)
+            server = await asyncio.create_subprocess_exec(*server_cmd, stderr=asyncio.subprocess.PIPE)
+            stderr_forwarder = asyncio.create_task(forward_stderr(server))
             await asyncio.sleep(1)
             await client.start_tcp(host, port)
 
@@ -228,6 +240,10 @@ async def fn(
         client.exit(None)
 
         await client.stop()
+
+        if stderr_forwarder:
+            stderr_forwarder.cancel()
+
         if server is not None and server.returncode is None:
             server.terminate()