reactivando / use-pubsub-js / 28134304037

100%

master: 80%

push

github

perf(pubsub): flatten the publish snapshot to one array (#89)

Replace the array-of-arrays snapshot (one array per hierarchy level) with a
single flat array built by direct push. Cuts allocations from O(levels) arrays
to one per publish (most impactful for hierarchical topics) and flattens the
delivery loop. Delivery order is unchanged — exact topic first, then ancestors,
subscription order within each — and is guarded by the existing order tests
(mutation-verified: reversing the snapshot fails 4 order tests).

No API or behavior change. The stable-debounce and useMemo-return ideas from the
perf audit were deliberately left out: the former subtly changes the
isImmediate+automatic rapid-message behavior, the latter touches hook return
identity — not worth the tiny allocation savings.

125 tests, 100% coverage, lint clean, e2e 12/12.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

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9 of 9 new or added lines in 1 file covered. (100.0%)

210 of 210 relevant lines covered (100.0%)

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