feat(browser): Include culture context with events

packages/browser/src/index.ts

@@ -75,6 +75,7 @@ export type { Span, FeatureFlagsIntegration } from '@sentry/core';
 export { makeBrowserOfflineTransport } from './transports/offline';
 export { browserProfilingIntegration } from './profiling/integration';
 export { spotlightBrowserIntegration } from './integrations/spotlight';
+export { cultureContextIntegration } from './integrations/culturecontext';
 export { browserSessionIntegration } from './integrations/browsersession';
 export { launchDarklyIntegration, buildLaunchDarklyFlagUsedHandler } from './integrations/featureFlags/launchdarkly';
 export { openFeatureIntegration, OpenFeatureIntegrationHook } from './integrations/featureFlags/openfeature';

packages/browser/src/integrations/culturecontext.ts

@@ -0,0 +1,58 @@
+import type { CultureContext, IntegrationFn } from '@sentry/core';
+import { defineIntegration, GLOBAL_OBJ } from '@sentry/core';
+
+const INTEGRATION_NAME = 'CultureContext';
+
+const _cultureContextIntegration = (() => {
+  return {
+    name: INTEGRATION_NAME,
+    preprocessEvent(event) {
+      const culture = getCultureContext();
+
+      if (culture) {
+        event.contexts = {
+          ...event.contexts,
+          culture: { ...culture, ...event.contexts?.culture },
+        };
+      }
+    },
+  };
+}) satisfies IntegrationFn;
+
+/**
+ * Captures culture context from the browser.
+ *
+ * Enabled by default.
+ *
+ * @example
+ * ```js
+ * import * as Sentry from '@sentry/browser';
+ *
+ * Sentry.init({
+ *   integrations: [Sentry.cultureContextIntegration()],
+ * });
+ * ```
+ */
+export const cultureContextIntegration = defineIntegration(_cultureContextIntegration);
+
+/**
+ * Returns the culture context from the browser's Intl API.
+ */
+function getCultureContext(): CultureContext | undefined {
+  try {
+    if (typeof (GLOBAL_OBJ as { Intl?: typeof Intl }).Intl === 'undefined') {
+      return undefined;
+    }
+
+    const options = Intl.DateTimeFormat().resolvedOptions();
+
+    return {
+      locale: options.locale,
+      timezone: options.timeZone,
+      calendar: options.calendar,
+    };
+  } catch {
+    // Ignore errors
+    return undefined;
+  }
+}

packages/browser/src/sdk.ts

@@ -12,6 +12,7 @@ import type { BrowserClientOptions, BrowserOptions } from './client';
 import { BrowserClient } from './client';
 import { breadcrumbsIntegration } from './integrations/breadcrumbs';
 import { browserApiErrorsIntegration } from './integrations/browserapierrors';
+import { cultureContextIntegration } from './integrations/culturecontext';
 import { browserSessionIntegration } from './integrations/browsersession';
 import { globalHandlersIntegration } from './integrations/globalhandlers';
 import { httpContextIntegration } from './integrations/httpcontext';
@@ -39,6 +40,7 @@ export function getDefaultIntegrations(_options: Options): Integration[] {
     linkedErrorsIntegration(),
     dedupeIntegration(),
     httpContextIntegration(),
+    cultureContextIntegration(),
     browserSessionIntegration(),
   ];
 }

packages/browser/test/integrations/culturecontext.test.ts

@@ -0,0 +1,194 @@
+import type { Event } from '@sentry/core';
+import * as SentryCore from '@sentry/core';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { cultureContextIntegration } from '../../src/integrations/culturecontext';
+
+describe('CultureContext', () => {
+  const originalIntl = globalThis.Intl;
+
+  beforeEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  afterEach(() => {
+    globalThis.Intl = originalIntl;
+  });
+
+  describe('preprocessEvent', () => {
+    it('adds culture context with locale and timezone', () => {
+      const mockResolvedOptions = vi.fn().mockReturnValue({
+        locale: 'en-US',
+        timeZone: 'America/New_York',
+      });
+
+      globalThis.Intl = {
+        DateTimeFormat: vi.fn().mockReturnValue({
+          resolvedOptions: mockResolvedOptions,
+        }),
+      } as unknown as typeof Intl;
+
+      // @ts-expect-error - mockReturnValue is not typed
+      vi.spyOn(SentryCore, 'GLOBAL_OBJ', 'get').mockReturnValue({
+        Intl: globalThis.Intl,
+      } as typeof SentryCore.GLOBAL_OBJ);
+
+      const integration = cultureContextIntegration();
+      const event: Event = {};
+
+      integration.preprocessEvent!(event, {}, {} as never);
+
+      expect(event.contexts?.culture).toEqual({
+        locale: 'en-US',
+        timezone: 'America/New_York',
+      });
+    });
+
+    it('preserves existing culture context values', () => {
+      const mockResolvedOptions = vi.fn().mockReturnValue({
+        locale: 'en-US',
+        timeZone: 'America/New_York',
+      });
+
+      globalThis.Intl = {
+        DateTimeFormat: vi.fn().mockReturnValue({
+          resolvedOptions: mockResolvedOptions,
+        }),
+      } as unknown as typeof Intl;
+
+      // @ts-expect-error - mockReturnValue is not typed
+      vi.spyOn(SentryCore, 'GLOBAL_OBJ', 'get').mockReturnValue({
+        Intl: globalThis.Intl,
+      } as typeof SentryCore.GLOBAL_OBJ);
+
+      const integration = cultureContextIntegration();
+      const event: Event = {
+        contexts: {
+          culture: {
+            calendar: 'gregorian',
+            display_name: 'English (United States)',
+          },
+        },
+      };
+
+      integration.preprocessEvent!(event, {}, {} as never);
+
+      expect(event.contexts?.culture).toEqual({
+        locale: 'en-US',
+        timezone: 'America/New_York',
+        calendar: 'gregorian',
+        display_name: 'English (United States)',
+      });
+    });
+
+    it('does not override existing locale and timezone', () => {
+      const mockResolvedOptions = vi.fn().mockReturnValue({
+        locale: 'en-US',
+        timeZone: 'America/New_York',
+      });
+
+      globalThis.Intl = {
+        DateTimeFormat: vi.fn().mockReturnValue({
+          resolvedOptions: mockResolvedOptions,
+        }),
+      } as unknown as typeof Intl;
+
+      // @ts-expect-error - mockReturnValue is not typed
+      vi.spyOn(SentryCore, 'GLOBAL_OBJ', 'get').mockReturnValue({
+        Intl: globalThis.Intl,
+      } as typeof SentryCore.GLOBAL_OBJ);
+
+      const integration = cultureContextIntegration();
+      const event: Event = {
+        contexts: {
+          culture: {
+            locale: 'de-DE',
+            timezone: 'Europe/Berlin',
+          },
+        },
+      };
+
+      integration.preprocessEvent!(event, {}, {} as never);
+
+      // Existing values should be preserved (not overwritten)
+      expect(event.contexts?.culture).toEqual({
+        locale: 'de-DE',
+        timezone: 'Europe/Berlin',
+      });
+    });
+
+    it('does not add culture context when Intl is not available', () => {
+      vi.spyOn(SentryCore, 'GLOBAL_OBJ', 'get').mockReturnValue({
+        Intl: undefined,
+      } as unknown as typeof SentryCore.GLOBAL_OBJ);
+
+      const integration = cultureContextIntegration();
+      const event: Event = {};
+
+      integration.preprocessEvent!(event, {}, {} as never);
+
+      expect(event.contexts?.culture).toBeUndefined();
+    });
+
+    it('handles errors gracefully when Intl.DateTimeFormat throws', () => {
+      globalThis.Intl = {
+        DateTimeFormat: vi.fn().mockImplementation(() => {
+          throw new Error('Intl error');
+        }),
+      } as unknown as typeof Intl;
+
+      // @ts-expect-error - mockReturnValue is not typed
+      vi.spyOn(SentryCore, 'GLOBAL_OBJ', 'get').mockReturnValue({
+        Intl: globalThis.Intl,
+      } as typeof SentryCore.GLOBAL_OBJ);
+
+      const integration = cultureContextIntegration();
+      const event: Event = {};
+
+      // Should not throw
+      expect(() => {
+        integration.preprocessEvent!(event, {}, {} as never);
+      }).not.toThrow();
+
+      expect(event.contexts?.culture).toBeUndefined();
+    });
+
+    it('preserves other contexts when adding culture context', () => {
+      const mockResolvedOptions = vi.fn().mockReturnValue({
+        locale: 'fr-FR',
+        timeZone: 'Europe/Paris',
+      });
+
+      globalThis.Intl = {
+        DateTimeFormat: vi.fn().mockReturnValue({
+          resolvedOptions: mockResolvedOptions,
+        }),
+      } as unknown as typeof Intl;
+
+      // @ts-expect-error - mockReturnValue is not typed
+      vi.spyOn(SentryCore, 'GLOBAL_OBJ', 'get').mockReturnValue({
+        Intl: globalThis.Intl,
+      } as typeof SentryCore.GLOBAL_OBJ);
+
+      const integration = cultureContextIntegration();
+      const event: Event = {
+        contexts: {
+          browser: {
+            name: 'Chrome',
+            version: '100.0',
+          },
+        },
+      };
+
+      integration.preprocessEvent!(event, {}, {} as never);
+
+      expect(event.contexts?.browser).toEqual({
+        name: 'Chrome',
+        version: '100.0',
+      });
+      expect(event.contexts?.culture).toEqual({
+        locale: 'fr-FR',
+        timezone: 'Europe/Paris',
+      });
+    });
+  });
+});