The ported suite passes in CI and fails locally on the same commit, same
Python (3.14.7) and byte-identical dependency versions (syrupy 6.0.0,
pytest 9.0.3, pytest-homeassistant-custom-component 0.13.365, HA
2026.9.2): tests/test_conversation.py::test_model_args fails with
"Snapshot 'test_model_args[subentry_options0]' does not exist!" even
though tests/snapshots/test_conversation.ambr contains exactly that key.
Cause: syrupy and pytest-homeassistant-custom-component both register a
`snapshot` fixture via the pytest11 entry point, and the plugin loaded
last wins. syrupy's stores snapshots in `__snapshots__/`;
HomeAssistantSnapshotExtension overrides dirname() to `snapshots/`,
which is where core's ported .ambr files are. Entry-point iteration
order is install/filesystem dependent, so which one wins varies per
machine -- confirmed by running with --snapshot-update locally, which
wrote a new file to tests/__snapshots__/ instead of finding the
committed one under tests/snapshots/.
That means the green CI run was luck, not design: any change to install
order could have flipped it, and the failure mode is a *missing*
snapshot, which reads like a stale fixture rather than a harness bug.
Fixed the way core's own tests/conftest.py does it -- redefine
`snapshot` in conftest, since a conftest fixture always takes precedence
over a plugin's. This is the one piece of core's conftest the port
dropped.
Local: 137 passed (was 136 passed, 1 failed). Matches CI's 137.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NxJYWgGJtCw13qUHZtG8ki
