tests: Catch tests that don't shut down background threadsjuerg/fork

3 files changed, 49 insertions, 0 deletions

diff --git a/src/buildstream/testing/_fixtures.py b/src/buildstream/testing/_fixtures.py
new file mode 100644
index 000000000..862cebe87
--- /dev/null
+++ b/src/buildstream/testing/_fixtures.py
@@ -0,0 +1,31 @@
+#
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+
+import psutil
+import pytest
+
+from buildstream import utils
+
+# Catch tests that don't shut down background threads, which could then lead
+# to other tests hanging when BuildStream uses fork().
+@pytest.fixture(autouse=True)
+def thread_check():
+    # xdist/execnet has its own helper thread.
+    # Ignore that for `utils._is_single_threaded` checks.
+    utils._INITIAL_NUM_THREADS_IN_MAIN_PROCESS = psutil.Process().num_threads()
+
+    yield
+    assert utils._is_single_threaded()
diff --git a/src/buildstream/testing/_sourcetests/conftest.py b/src/buildstream/testing/_sourcetests/conftest.py
new file mode 100644
index 000000000..f16c1e9ad
--- /dev/null
+++ b/src/buildstream/testing/_sourcetests/conftest.py
@@ -0,0 +1,17 @@
+#
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+
+from .._fixtures import thread_check  # pylint: disable=unused-import
diff --git a/tests/conftest.py b/tests/conftest.py
index 7728fb5c8..0e39943d3 100755
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -23,6 +23,7 @@ import os
 import pytest
 
 from buildstream.testing import register_repo_kind, sourcetests_collection_hook
+from buildstream.testing._fixtures import thread_check  # pylint: disable=unused-import
 from buildstream.testing._forked import forked_run_report
 from buildstream.testing.integration import integration_cache  # pylint: disable=unused-import