Bundle-level review caught an implicit coupling in useCanvasViewport
between two distinct fit effects:
- settle fit: 1200ms one-shot when provisioning transitions to zero
(deploy just finished — settle on the whole org once)
- tracking fit: 500ms debounced per molecule:fit-deploying-org event
(track the org's bounds as children land during the deploy)
Both effects shared a single autoFitTimerRef, so each one's
clearTimeout call could silently cancel the other's pending fit.
Today's behavior happened to land in the right order out of luck —
the tracking handler fires per-arrival during the deploy, then the
settle effect arms after the last child completes. But nothing in
the code enforces that ordering; a future refactor that, say,
fires the settle effect from the same event sequence as the
tracking timer (mid-deploy status flicker) would silently drop the
settle fit because the tracking timer's clearTimeout ran last.
Splitting into settleFitTimerRef + trackingFitTimerRef makes the
two effects fully independent. Cleanup clears both. Tests still pass
(995/995); the refactor is mechanical.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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