Shadow: ✅ improve E2E test reliability on BrowserStack (v1)#89
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Shadow: ✅ improve E2E test reliability on BrowserStack (v1)#89allspain wants to merge 3 commits into
allspain wants to merge 3 commits into
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In BrowserStack, the browser runs remotely and the round-trip latency to the test server can be significant. A fixed idle wait duration may not be sufficient to catch all in-flight requests. We now measure the latency once per worker before tests run and use `Math.max(500, latency * 1.5)` as the idle wait duration.
…avicon requests - waitForServersIdle() now waits idleWaitDuration ms before checking idle state, so in-flight browser requests have time to reach the server before idle is declared - replace /ok?duration=200 with a dedicated /flush route that delays 200ms and returns HTML with an empty favicon, preventing spurious favicon requests during event flushing - skip teardown flushEvents() when already on /flush to avoid redundant work - add empty favicon link to all test pages to suppress /favicon.ico requests
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Shadow Review — PR
#4494v1Source:
DataDog/browser-sdk#4494Commit:
6ad64642884f006f2e99e172679f051209bb4eb9Timestamp: 2026-04-16T15:07:52Z
Original PR Description
Motivation
E2E tests running on BrowserStack have been flaky due to high network latency between the remote browser and the local test server. Several issues compounded this:
waitForServersIdle()to return before all requests had arrivedwaitForServersIdle()was called, making it return immediately despite pending network activity/favicon.icorequests that added noise to server idle trackingChanges
Math.max(500, latency * 1.5)as the idle wait durationwaitForServersIdle()now waitsidleWaitDurationms upfront to let in-flight requests arrive before checking idle state/flushroute (replaces/ok?duration=200) that delays 200ms and returns HTML — used when navigating away to flush SDK events, including session replay Web Worker segments/favicon.icorequests by embedding an empty favicon in all test pagesflushEvents()in teardown when the page is already on/flushTest instructions
Run the E2E tests on BrowserStack and verify that previously flaky tests pass consistently.
Checklist