Tier T2 — composition rather than units. The registry tests construct awkward
states directly; these feed the pieces real 480x360 footage with the cuts, gaps
and crowded frames that synthetic input does not produce.
Six cases:
- fixture integrity: exact frame and face counts, contiguous face_offset, and
the embedder identity each dump carries (GR-004). The counts are asserted
exactly rather than approximately, which was impossible before AR-004 — what
a lossy run dropped depended on timing.
- determinism: replaying a fixture twice gives identical track ids and windows.
This is the property the whole fixture strategy rests on; without it every
golden output derived from a fixture is unreliable and the CI replay tier is
worthless.
- every face is assigned a track, and flush leaves nothing open — a track still
live at EOF is a window that never reaches the output.
- windows are well-formed and inside the clip. A window ends at the last
sighting, so it can never extend past the footage that produced it.
- a longer extinction window yields fewer, longer tracks. On the sparse fixture
(140 faces over 385 frames) that is the difference the constant actually
makes: absorbing a gap versus splitting a window.
- the cut-heavy fixture still contains cuts. This guards the corpus, not the
code: a regeneration that produced cut-free fixtures would leave the
association tests passing while silently testing nothing.
Driving the functors directly rather than through a KPN network is deliberate —
no threads, no channels, no scheduling, so the same input gives the same output.
Suite: 86 cases, 6106 assertions.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
TRACES: AR-004, AR-012, AR-013, VR-001, VR-002 | SR-002
