fix(performance-monitor-plugin): 1ms-precise time display#269
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V3RON merged 1 commit intoMay 14, 2026
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…splay formatDuration drops fake decimals for milliseconds — clock is 1ms accurate, so .toFixed(2) was fabricating precision. Durations >= 1s display 3 decimals (1.234s) to preserve the same 1ms precision in seconds. Non-zero sub-millisecond values render as "<1ms" to distinguish "fired but fast" from "not measured." Rounding now happens before unit selection, so 999.6ms displays as 1.000s rather than 1000ms. formatTime now produces a stable 24h HH:MM:SS.mmm format so the millisecond component is visible alongside HH:MM:SS in the Mark / Metric / Measure / Resource / ReactNativeMark details panels and on the session-started line. Inline formatTime duplicates in MarkDetails, MetricDetails, and SessionDuration are replaced with imports from utils so the new format propagates everywhere. SessionDuration keeps its own whole-second formatDuration for the always-ticking session-length display. ResourceDetails.formatPhase keeps its 0/undefined → "—" special case but routes non-zero values through formatDuration so resource timing phases honor the same precision rule. Adds vitest tests covering the boundary behaviors (zero, sub-1ms, ms rounding, ms/s switch at 1000, round-across-boundary at 999.6, ms padding, midnight, end-of-day).
V3RON
approved these changes
May 14, 2026
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Summary
formatDurationno longer fakes precision: ms values round to integer (.toFixed(2)was fabricating 0.01ms detail the clock can't provide),>= 1svalues show 3 decimals (1.234s) for the same 1ms-precision invariant, and non-zero sub-1ms values display as<1msto distinguish "fired but fast" from "not measured." Rounding happens before the unit switch, so999.6msdisplays as1.000srather than1000ms.formatTimenow produces a stable 24hHH:MM:SS.mmmformat — the millisecond component is visible alongside HH:MM:SS on every "Recorded at" / "Started" / "Start Time" / "End Time" line across Mark / Metric / Measure / Resource / ReactNativeMark / SessionDuration.formatTimeduplicates inMarkDetails,MetricDetails, andSessionDurationreplaced with imports fromutils.ResourceDetails.formatPhasekeeps its0/undefined → "—"special case but routes non-zero values throughformatDurationso resource timing phases honor the same precision rule.SessionDurationkeeps its own whole-secondformatDurationfor the always-ticking session-length display.Test plan
pnpm --filter @rozenite/performance-monitor-plugin test— all 26 tests pass (10 newutils.test.ts+ 16 existing for serialize/derive-startup-phases).pnpm --filter @rozenite/performance-monitor-plugin typecheck— clean.pnpm --filter @rozenite/performance-monitor-plugin lint— clean.HH:MM:SS.mmm(24h, three-digit ms padding).1.234sstyle for ≥1s.performance.markthat fires near-instantly displays as<1ms, not0ms.