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+---
+'@object-ui/plugin-grid': patch
+---
+
+fix(plugin-grid): a bulk action's confirm sentence formats its numbers and dates in the viewer's display locale
+
+Clause-②: no
+Metadata-protocol: none
+
+A bulk `confirmText` such as `Set the amount to {{ amount | currency:EUR }} on {{ count }} records?` formatted its numbers and dates in `en-US` for every viewer, while the same action's single-record confirm formats them in the viewer's language. `BulkActionDialog` now reads `useDisplayLocale()`, the locale every date, number and currency renderer and the console's action runners read, and `bulkConfirmText` takes it as an optional third argument, handed to `fillTemplateHoles`'s locale channel apart from the template roots. A German viewer reads `1.234.567,50 €`; with no locale handed, the sentence formats in `en-US` as before.
+
+What to do: nothing.
@@ -0,0 +1,115 @@
+/**
+ * ObjectUI
+ * Copyright (c) 2024-present ObjectStack Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+/**
+ * objectstack#26307 — a bulk `confirmText` formats its numbers and dates in
+ * the viewer's display locale, the one `useDisplayLocale()` resolves, the way
+ * the same action's single-record confirm does since objectstack#26232. It
+ * used to format them in `en-US` for every viewer.
+ *
+ * Two halves:
+ *   - the helper `bulkConfirmText`: its `locale` argument reaches the
+ *     formatters, and an absent one keeps `en-US`;
+ *   - the real `BulkActionDialog` under a real `I18nProvider` and
+ *     `LocalizationProvider`: the confirm sentence formats in the tenant's
+ *     display locale.
+ *
+ * Expected strings come from `Intl` itself, so a newer ICU cannot drift them.
+ */
+import { describe, it, expect, vi, beforeAll, afterEach } from 'vitest';
+import React from 'react';
+import { render, screen, cleanup, fireEvent } from '@testing-library/react';
+import '@testing-library/jest-dom';
+import { I18nProvider, LocalizationProvider } from '@object-ui/i18n';
+import type { BulkActionDef, BulkActionParam } from '@object-ui/types';
+
+import { BulkActionDialog } from '../components/BulkActionDialog';
+import { bulkConfirmText } from '../components/bulkConfirmText';
+
+beforeAll(() => {
+  if (!Element.prototype.scrollIntoView) {
+    Element.prototype.scrollIntoView = vi.fn() as any;
+  }
+});
+
+afterEach(() => cleanup());
+
+const AMOUNT_VALUE = 1234567.5;
+const DUE_VALUE = '2026-10-26';
+const money = (tag: string) => new Intl.NumberFormat(tag, { style: 'currency', currency: 'EUR' }).format(AMOUNT_VALUE);
+const fixed2 = (tag: string) =>
+  new Intl.NumberFormat(tag, { minimumFractionDigits: 2, maximumFractionDigits: 2 }).format(AMOUNT_VALUE);
+const longDate = (tag: string) => new Intl.DateTimeFormat(tag, { dateStyle: 'long' }).format(new Date(DUE_VALUE));
+
+const AMOUNT: BulkActionParam = { name: 'amount', label: 'Amount', type: 'number' };
+const DUE: BulkActionParam = { name: 'due', label: 'Due', type: 'date' };
+
+function fill(source: string, locale?: string) {
+  return bulkConfirmText(source, { count: 2, params: [AMOUNT, DUE], values: { amount: AMOUNT_VALUE, due: DUE_VALUE } }, locale);
+}
+
+describe('bulkConfirmText formats in the locale it is handed (objectstack#26307)', () => {
+  it('formats a currency, a number and a date hole in a German display locale', () => {
+    expect(money('de-DE')).not.toBe(money('en-US'));
+    expect(fill('Set {{ amount | currency:EUR }} on {{ count }} records?', 'de-DE')).toBe(`Set ${money('de-DE')} on 2 records?`);
+    expect(fill('Set {{ amount | number:2 }}?', 'de-DE')).toBe(`Set ${fixed2('de-DE')}?`);
+    expect(fill('Due {{ due | date:long }}?', 'de-DE')).toBe(`Due ${longDate('de-DE')}?`);
+  });
+
+  it('formats a date hole in a Chinese display locale', () => {
+    expect(longDate('zh-CN')).not.toBe(longDate('en-US'));
+    expect(fill('Due {{ due | date:long }}?', 'zh-CN')).toBe(`Due ${longDate('zh-CN')}?`);
+  });
+
+  it('keeps en-US when no locale is handed', () => {
+    expect(fill('Set {{ amount | currency:EUR }}, due {{ due | date:long }}?')).toBe(
+      `Set ${money('en-US')}, due ${longDate('en-US')}?`,
+    );
+  });
+});
+
+const ROWS = [{ id: 'r1', name: 'Acme' }, { id: 'r2', name: 'Globex' }];
+
+const REPRICE: BulkActionDef = {
+  name: 'reprice',
+  label: 'Reprice',
+  operation: 'update',
+  params: [{ ...AMOUNT, default: AMOUNT_VALUE }],
+  confirmText: { dialect: 'template', source: 'Set the amount to {{ amount | currency:EUR }} on {{ count }} records?' },
+};
+
+function openDialog(tenantLocale: string | undefined) {
+  render(
+    <I18nProvider config={{ defaultLanguage: 'en', detectBrowserLanguage: false }} persistLanguage={false}>
+      <LocalizationProvider value={{ locale: tenantLocale }}>
+        <BulkActionDialog
+          def={REPRICE}
+          rows={ROWS}
+          resource="account"
+          dataSource={{ update: vi.fn(async () => ({})), delete: vi.fn(async () => ({})) } as any}
+          open
+          onClose={() => {}}
+        />
+      </LocalizationProvider>
+    </I18nProvider>,
+  );
+}
+
+describe('BulkActionDialog formats its confirm sentence in the display locale (objectstack#26307)', () => {
+  it('formats a currency hole in the tenant display locale', async () => {
+    openDialog('de-DE');
+    fireEvent.click(await screen.findByRole('button', { name: 'Next' }));
+    expect(await screen.findByText(`Set the amount to ${money('de-DE')} on 2 records?`)).toBeInTheDocument();
+  });
+
+  it('formats in the UI language when no tenant locale is set', async () => {
+    openDialog(undefined);
+    fireEvent.click(await screen.findByRole('button', { name: 'Next' }));
+    expect(await screen.findByText(`Set the amount to ${money('en')} on 2 records?`)).toBeInTheDocument();
+  });
+});