[roger-zhangg]

Which issue(s) does this change fix?

N/A

Why is this change necessary?

sync-code and sync-watch have failed on every scheduled integration run since pytest was bumped 9.0.3 → 9.1.1 (#9095, 2026-07-31).

Run	pytest	sync-code
2026-07-30 (last pre-bump)	9.0.3	success — 89 passed, 1 rerun
2026-08-14	9.1.1	failure — 37 passed, 52 errors, 156 rerun

The logs show only pytest's own internal assertion, assert not self._finalizers (_pytest/fixtures.py:1221), with nothing pointing at the real cause. Reproducible in ten lines, no AWS needed:

class TestFixt:
    @pytest.fixture(scope="class")
    def fixt(self): yield
    def test_1(self, fixt): pass
    def test_2(self, fixt): pass

pytest 9.0.3           -> 2 passed
pytest 9.1.1 -W error  -> 2 errors

Four links:

1. pytest 9.1 deprecated class-scoped fixtures declared as instance methods (PytestRemovedIn10Warning). TestSyncCodeBase.execute_infra_sync / sync_code_base are exactly this shape.
2. pytest.ini sets filterwarnings = error, turning that warning into a setup failure on the first test of every affected class.
3. pytest then raises its own internal AssertionError for the remaining tests in the class — upstream pytest-dev/pytest#14775, still open. Root cause is fixtures.py:1147: finish() early-returns when cached_result is None without clearing _finalizers.
4. --reruns 3 hides the cause. pytest-rerunfailures reports only the final attempt, so the real warning is discarded and only the internal AssertionError survives — which is why the CI logs contain zero occurrences of the actual error.

Confirmed link 4 directly, same test with and without --reruns:

without --reruns:  test_1 => PytestRemovedIn10Warning   <- real cause
                   test_2 => AssertionError
with --reruns 3:   test_1 => AssertionError             <- cause gone

The counts line up exactly: 52 errors × 3 reruns = 156 reruns (sync-watch: 12 × 3 = 36).

How does it address the issue?

Marks the warning as ignored on the three classes that declare these fixtures — TestSyncCodeBase, LogsIntegTestCases, TestTracesCommand. Six lines total.

Safe here specifically: these fixtures assign to the class (TestSyncCodeBase.stack_name = ...), not to self, so the hazard the deprecation warns about — attributes set on self being invisible to tests — does not apply to them.

A class mark rather than a pytest.ini entry, so the rest of the suite still fails on this warning. And a class mark rather than a module-level pytestmark, because pytestmark is module-scoped while TestSyncCodeBase is subclassed from other modules (test_sync_build_in_source.py, test_sync_adl.py) — which is precisely why one base class took out both sync-code and sync-watch.

What side effects does this change have?

Deferred, not avoided: converting these fixtures is required before pytest 10 removes the behaviour. Left out on purpose — it is not mechanical. execute_infra_sync derives its stack name from self._method_to_stack_name(self.id()), and unittest's id() needs an instance, so any conversion changes live CloudFormation stack names. All three autouse fixtures also assert via self.assertEqual, which under @classmethod would bind the first argument as self rather than fail loudly. That belongs in its own PR, verified against real AWS.

Testing

• Against the repo's real pytest.ini, the same parameterized class-scoped shape goes 6 errors → 6 passed with the mark
• An unmarked equivalent still errors, so suite-wide protection is intact
• Confirmed pytest resolves the mark through the MRO for subclasses carrying their own marks (TestLogsCommandWithRegularStack)
• tests/integration/{sync,logs,traces} collect 266 tests; black and ruff clean

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Review the generative AI contribution guidelines
• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests

[aws-sam-tooling-bot]

Code Review Results

Reviewed: e1f4bf6..166ee89
Files: 3
Comments: 1

[aws-sam-tooling-bot]

[GENERAL] The justification in the comment is only half true, and that matters for what happens next.

The fixtures do assign results to the class (TestSyncCodeBase.template_path, TestSyncCodeBase.stack_name), but they also read instance state and call unittest methods on self:

@pytest.fixture(scope="class")
def execute_infra_sync(self):
   if self.test_data_path is None: ...
   TestSyncCodeBase.stack_name = self._method_to_stack_name(self.id())   # instance-derived
   ... dependency_layer=self.dependency_layer, image_repository=self.ecr_repo_name, kms_key_id=self.kms_key

@pytest.fixture(autouse=True, scope="class")
def sync_code_base(self, execute_infra_sync):
   self.assertEqual(...)   # unittest assertion on a per-test instance

The same holds in the other two files: deploy_testing_stack reads self.test_template_folder and logs_base / sync_code_base call self.assertEqual. That is exactly the binding the deprecation targets — the self a class-scoped fixture receives is an instance created for one particular test in the class (here, the first one), so self.id() and the parameterized_class attributes come from an arbitrary member of the class rather than from the class itself. So the pattern is being used, not "inapplicable"; the suppression defers the migration rather than documenting a false positive.

Two consequences worth addressing before merge:

• Remove before pytest 10 reads as "delete this line," but deleting it without converting the fixtures will hard-fail the suite. Please state the required follow-up explicitly (e.g., move the shared setup into setUpClass/a request.cls-based fixture, or make the fixture a @classmethod/@staticmethod and replace self.assertEqual with plain assert), and ideally link a tracking issue.
• Because the mark sits on the class, it silences this warning for every class-scoped fixture added to these classes later, including cases where the instance binding genuinely is a bug. Applying the filter narrowly (only where needed) or keeping it in one place with a pointer to the follow-up work limits that blast radius.

The unblock itself is reasonable; the ask is that the comment describe why the suppression is temporary rather than assert the deprecation does not apply.

[valerena]

I agree with the bot. If the extra info we're adding is not correct, let's just change to something simpler so it's not confusing.

# Deprecated in pytest 9.1. Fix before pytest 10.

[roger-zhangg]

Thanks for the suggestion, applied the fix

[aws-sam-tooling-bot]

Code Review Results

Reviewed: e1f4bf6..d373c81
Files: 3
Comments: 1