Report crashes of the test process in CI logs

.github/workflows/test_pyqt5.yml

@@ -117,7 +117,27 @@ jobs:
     - name: Lint with Ruff
       run: ruff check --output-format=github datalab
     - name: Test with pytest
-      run: pytest -v --tb=long
+      run: |
+        # Keep the core dump of a crashed test process, for the backtrace step below
+        sudo mkdir -p /tmp/cores && sudo chmod 1777 /tmp/cores || true
+        sudo sysctl -q -w kernel.core_pattern=/tmp/cores/core.%p || true
+        ulimit -c unlimited || true
+        pytest -v --tb=long
+    - name: Native backtrace of crashed test process
+      if: failure()
+      run: |
+        shopt -s nullglob
+        cores=(/tmp/cores/core.*)
+        if [ ${#cores[@]} -eq 0 ]; then
+          echo "No core dump found"
+          exit 0
+        fi
+        sudo apt-get install -y gdb
+        python_exe="$(python -c 'import sys; print(sys.executable)')"
+        for core in "${cores[@]}"; do
+          echo "===== Backtrace of $core"
+          gdb -batch -ex "thread apply all bt 50" "$python_exe" "$core"
+        done
 
   build_latest:
     if: ${{ github.event_name == 'schedule' || (github.event_name == 'workflow_dispatch' && (github.event.inputs.job_to_run == 'all' || github.event.inputs.job_to_run == 'build_latest')) }}

datalab/tests/conftest.py

@@ -47,6 +47,9 @@ def reset_datalab_configuration():
     ensure_initialized(load_user_config=False)
     reset_to_defaults()
     Conf.rpc_server_enabled.set(False)
+    # Keep pytest's faulthandler, which reports crashes in the test output: the
+    # application context would redirect it to a log file, then disable it
+    Conf.faulthandler_enabled.set(False)
     try:
         yield
     finally: