Fix flaky tests by running them in isolation with pytest-forked

Author: krassowski

jupyter_server_nbmodel/tests/test_handlers.py

@@ -221,6 +221,7 @@ async def fake_execute(client, ydoc, snippet, metadata, stdin_hook):
     assert "error" in results[uid], f"Expected an 'error' key in results[{uid!r}]"
     assert "simulated failure" in results[uid]["error"]
 
+
 @pytest.mark.timeout(TEST_TIMEOUT)
 async def test_execution_timing_metadata(jp_root_dir, jp_fetch, pending_kernel_is_ready, rtc_create_notebook, jp_serverapp):
     snippet = "a = 1"

pyproject.toml

@@ -40,6 +40,7 @@ test = [
   "pytest-cov",
   "pytest-jupyter[server]>=0.6",
   "pytest-timeout",
+  "pytest-forked",
   "jupyter-server-ydoc[test]>=1.0.0b1",
   "jupyter-server-fileid",
 ]
@@ -90,6 +91,7 @@ source_dir = "src"
 build_dir = "jupyter_server_nbmodel/labextension"
 
 [tool.pytest.ini_options]
+addopts = "-vv --forked"
 filterwarnings = [
   "error",
   "ignore:Unclosed context <zmq.asyncio.Context:ResourceWarning",