Findings 12-15 from the review. All four are group/solo UI state, none
reachable before the id-space fix made group writes work at all.
14 — TimelineGroupRow called the THROWING useTimelineEditContext where
every sibling row calls the optional one. Timeline.test.ts already
asserted the timeline renders outside the provider; it passed because
its fixture had no groups. One grouped clip took the whole timeline
render down, not just the row. The new test is that assertion with a
group on screen, and it fails against the old hook.
13 — A collapsed group left its members in `tracks`, so row geometry
reserved a full row each while buildTimelineLogicalRows had already
stopped emitting them: TimelineLanes rendered null into reserved space,
giving a group header trailed by its members' worth of blank,
unreachable dead space. Members are now emitted only while the group is
expanded, so the row list and the logical rows agree by construction.
(Zeroing the heights instead does not work — createTimelineRowGeometry
deliberately reads a non-positive height as "invalid, use TRACK_H".)
Membership still lands in trackGroupOf: collapsed is hidden, not
ungrouped.
12 — groupInfoCache is a WeakMap keyed on the preview Document, and
group edits are applied as live patches precisely so the iframe never
reloads, so the key never changed and the entry never dropped. A muted
group could not be unmuted (the header kept reading the cached
`hidden:false` and re-wrote data-hidden), the bus slider snapped back,
and a second FX preset built on a stale chain, discarding the first.
Every live group write now drops the entry.
15 — Solo leaked two ways. createTimelineResetState never cleared
`soloed`, so switching composition carried ids that match nothing in the
new document — which is exactly the state that silences every track
while the banner still names a clip that is not there. And the solo
bridge's effect deps do not change across a preview reload, so the
reloaded runtime kept an empty set while the button stayed lit and the
banner still claimed "Hearing only X". Solo now rides
applyPreviewAudioFlags, the same reload-surviving path as the mute and
canary state.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Six of the fifteen findings from the max-effort review of the audio
groups / mute-solo / pitch-shift stack. Nothing in the stack is merged;
this sits on top of wa-24-timeline-fx.
The id space (findings 1-3). Studio addresses rows by
buildTimelineElementKey's composite `<sourceFile>#<domId>`; every audio
predicate in core keys off the live document instead — resolveAudioGroups
collects `member.id`, isAudibleUnderSolo compares `el.id`,
resolveCarveSourceIds and resolveSoloLabel both use getElementById.
Nobody checked the boundary, so:
* solo put a composite key in the set the runtime matches against
`el.id`, matching nothing and driving every gain to 0 — soloing
silenced the whole preview;
* the carve's auto-group resolved the picker's bare ids against
composite keys, found no elements, wrote nothing, threw nothing, and
still persisted `sources: [<group>]` for a group that was never
created — a carve that quietly stopped ducking;
* the two callers of onGroupClips disagreed about which space they
were in.
Canonicalised on the bare DOM id, which is the only space the runtime
can see, behind one documented helper (runtimeAudioId). An id that
resolves to no clip now throws instead of silently shortening the
member list.
The group element (finding 4). Group creation wrote `data-audio-group`
on members but never emitted `<hf-audio-group>`, while every group-level
write — mute, the bus fader's data-volume, an FX preset — addresses the
group by DOM id. Groups the product created were exactly the groups
nothing could edit. Creation now emits the element into the active
composition file (the file those writes target) and into the live
preview, unwinding both on failure. Group ids are validated before being
interpolated into markup.
The canary leaks (findings 5-6). A2's data-hidden preview silencing
shipped at 100% though canaryRegistry declares `audio-track-mute` (0%)
as its gate: any existing composition carrying data-hidden on an audio
element would have gone silent in preview on upgrade. Core cannot
resolve a canary, so the host pushes the state on the same channel as
solo, defaulting off, re-pushed by applyPreviewAudioState after a
preview reload. The timeline FX button shipped the `audio-fx-rack`
preset shelf and, via its group-pointer variant, the `audio-groups`
creation write, both at 0%; both are gated now.
Tests. Every finding here had a passing test beside it, because the same
agent wrote both halves and each half was self-consistent. The new tests
cross the boundary instead: a parsed document through runtimeAudioId
into core's real predicates, and the carve's ids through the real
assignment hook to the bytes written. Each was mutation-checked against
the pre-fix code.
Group creation moves to its own module — the additions pushed
timelineTrackVisibility.ts past the 600-line ceiling. Also swaps two raw
NUL bytes in useFxCarve.ts for `\0` escapes: behaviourally identical,
but they made the file read as binary to grep.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
