Add test

dev-packages/browser-integration-tests/suites/transport/offline/flush/subject.js

@@ -0,0 +1,7 @@
+setTimeout(() => {
+  Sentry.captureMessage(`foo ${Math.random()}`);
+}, 500);
+
+setTimeout(() => {
+  Sentry.flush();
+}, 2000);

dev-packages/browser-integration-tests/suites/transport/offline/flush/test.ts

@@ -0,0 +1,47 @@
+import { expect } from '@playwright/test';
+import type { Event } from '@sentry/core';
+
+import { sentryTest } from '../../../../utils/fixtures';
+import { getMultipleSentryEnvelopeRequests } from '../../../../utils/helpers';
+
+function delay(ms: number) {
+  return new Promise(resolve => setTimeout(resolve, ms));
+}
+
+sentryTest('should flush event', async ({ getLocalTestUrl, page }) => {
+  // makeBrowserOfflineTransport is not included in any CDN bundles
+  if (process.env.PW_BUNDLE && process.env.PW_BUNDLE.startsWith('bundle')) {
+    sentryTest.skip();
+  }
+
+  const url = await getLocalTestUrl({ testDir: __dirname });
+
+  // This would be the obvious way to test offline support but it doesn't appear to work!
+  // await context.setOffline(true);
+
+  let abortedCount = 0;
+
+  // Abort all envelope requests so the event gets queued
+  await page.route(/ingest\.sentry\.io/, route => {
+    abortedCount += 1;
+    return route.abort();
+  });
+  await page.goto(url);
+  await delay(1_000);
+  await page.unroute(/ingest\.sentry\.io/);
+
+  expect(abortedCount).toBe(1);
+
+  // The previous event should now be queued
+
+  // It should get flushed after a few seconds
+  const eventData = await getMultipleSentryEnvelopeRequests<Event>(page, 2, { timeout: 4_000 });
+
+  // Filter out any client reports
+  const events = eventData.filter(e => !('discarded_events' in e)) as Event[];
+
+  expect(events).toHaveLength(1);
+
+  // The next two events will be message events starting with 'foo'
+  expect(events[0].message?.startsWith('foo'));
+});