* feat(tests): add Blockbuster runtime gate for event-loop blocking IO
Adds a strict runtime gate that fails CI when sync blocking IO calls run
on the asyncio event loop thread through DeerFlow business code.
Components:
- backend/tests/support/detectors/blocking_io_runtime.py — Blockbuster
context scoped to `app.*` and `deerflow.*` so test infrastructure,
pytest internals, and third-party libraries stay silent.
- backend/tests/blocking_io/conftest.py — pytest_runtest_protocol
hookwrapper that wraps every item (setup + call + teardown) with the
strict context. Respects `@pytest.mark.allow_blocking_io` opt-out.
- backend/tests/blocking_io/test_skills_load.py — regression anchor for
the #1917 fix (asyncio.to_thread offload around
LocalSkillStorage.load_skills).
- backend/tests/blocking_io/test_sqlite_lifespan.py — regression anchor
for the #1912 fix (asyncio.to_thread offload around
ensure_sqlite_parent_dir).
- backend/tests/blocking_io/test_gate_smoke.py — meta-test asserting the
gate actually catches unoffloaded blocking IO and that the
`@pytest.mark.allow_blocking_io` opt-out works.
- backend/Makefile — `make test-blocking-io` target.
- .github/workflows/backend-blocking-io-tests.yml — hard-fail PR gate on
ubuntu-latest. Windows matrix deferred to follow-up.
Dependencies:
- blockbuster>=1.5.26,<1.6 added to dev group.
Coverage boundary (called out in PR body): the gate only catches blocking
IO on code paths the test suite actually exercises. Static AST inventory
(separate, informational) is the complementary coverage tool. Three blind
spot categories — untested paths, mocked-away paths, env-mismatched paths
— are documented in the PR description.
Findings surfaced while authoring this PR:
- resolve_sqlite_conn_str in runtime/store/_sqlite_utils.py:19 does sync
Path.resolve() -> os.path.abspath on the lifespan loop thread, ahead of
the #1912 fix. Not addressed here; tracked as follow-up.
Tests: 4 passed locally (`make test-blocking-io`).
Lint/format: clean (`ruff check` and `ruff format --check`).
* fix(tests): scope Blockbuster gate to blocking-io suite
* fix(tests): harden Blockbuster runtime gate
* test(blocking-io): add project rule extension point
* test(blocking-io): address review cleanup
e344be8d94