[plugin-gantt] the tasks useMemo omits tenantCurrency, so tooltip currency can render stale

[yinlianghui]

Pre-existing, found while threading the display locale through the same useMemo for #4272. Filed rather than fixed — out of that card's ruled surface.

The gap

packages/plugin-gantt/src/ObjectGantt.tsx — the tasks memo formats every tooltip value eagerly inside its callback, including currency:

case 'currency':
  return formatCurrency(Number(value), resolveFieldCurrency(def as any, tenantCurrency));

but tenantCurrency (from useLocalization()) is not in the memo's dependency array, which lists only [data, ganttConfig, objectSchema].

Why it can be observed

useLocalization() is fed by GET /api/v1/auth/me/localization, which is cosmetic and non-blocking — it resolves after first paint. So the first tasks computation runs with tenantCurrency still undefined, and when the tenant's real currency arrives none of data / ganttConfig / objectSchema has changed, the memo does not recompute, and the tooltip keeps the fallback currency until something unrelated invalidates it.

This is the same class of bug as the locale one #4272 fixed, in the currency channel: a value formatted eagerly inside a memo has to be a dependency of that memo. #4272's PR adds displayLocale to this very array for exactly that reason and deliberately did not touch tenantCurrency, which is a different channel and a different card.

Fix sketch

Add tenantCurrency to the dependency array. The red-first case is a gantt with a currency tooltip field whose LocalizationProvider currency arrives after the first render, asserting the tooltip picks up the late value.

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[yinlianghui]

CLAIM — session_017Qqyix2QcnpUC9XeYVDzx3, branch claude/issue-4542-gantt-currency-dep. Dispatching a dev agent now.

PM ruling (delegated decision authority; maintainer veto window open — record objections here): the currency twin of #4544's locale-dep fix, in the same memo:

1. Add tenantCurrency (the exact identifier the memo body reads — measure it) to plugin-gantt's tasks useMemo dependency array, so tooltip currency re-formats when the tenant currency endpoint resolves after first paint.
2. Red-first with the staleness repro: mock the currency channel to resolve AFTER initial render (deferred promise), assert the tooltip currency is stale/default pre-fix and re-renders correct post-fix. Predict the split in writing. If the memo reads currency through a stable reference that never changes identity (measure first), the premise inverts — STOP and report rather than adding a dead dep.
3. Pins: fix(fields): the date formatter's last three en-US channels thread the display locale (#4272) #4544's displayLocale dep and all its threading pins stay green; the full plugin-gantt suite green; en/currency-default rendering byte-identical when the channel resolves before first paint.
4. Changeset: '@object-ui/plugin-gantt': patch (module-local behavior fix). Never major.

Mutual exclusion: plugin-gantt untouched by all in-flight cards (#4527 studio, #4528 dashboard/list, #4254 kanban, #4541 plugin-grid). #4544 is on main — base directly on current origin/main, no gate.

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Generated by Claude Code

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Generated by Claude Code