Fix #3517: CreateCDPSessionAsync never delivers events for worker targets - #3518
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…gets Worker-type CDP sessions buffer early method-events until FlushEarlyMessages() is called, but that was only wired up for internal consumers (CdpWebWorker, blocked service worker registration). ITarget.CreateCDPSessionAsync() never flushed, so every event on a manually-created worker/service-worker session (e.g. Debugger.scriptParsed) sat in the buffer forever. Flushing also exposed a latent bug in FlushEarlyMessages(): the null-conditional invoke `_messageReceived?.Invoke(this, _bufferedMessages.Dequeue())` never evaluates Dequeue() when nobody has subscribed yet, since `?.` short-circuits the whole argument list - spinning the drain loop forever instead of clearing the queue. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
BidiWorkerTarget.CreateCDPSessionAsync always throws PuppeteerException("Not
supported"), so the #3517 regression test added for CreateCDPSessionAsync on
a ServiceWorker target doesn't apply there.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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Updated [PuppeteerSharp](https://github.com/hardkoded/puppeteer-sharp) from 25.3.3 to 25.3.4. <details> <summary>Release notes</summary> _Sourced from [PuppeteerSharp's releases](https://github.com/hardkoded/puppeteer-sharp/releases)._ ## 25.3.4 ## What's Changed * Fix #3517: CreateCDPSessionAsync never delivers events for worker targets by @kblok in hardkoded/puppeteer-sharp#3518 **Full Changelog**: hardkoded/puppeteer-sharp@v25.3.3...v25.3.4 Commits viewable in [compare view](hardkoded/puppeteer-sharp@v25.3.3...v25.3.4). </details> [](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting `@dependabot rebase`. [//]: # (dependabot-automerge-start) [//]: # (dependabot-automerge-end) --- <details> <summary>Dependabot commands and options</summary> <br /> You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot show <dependency name> ignore conditions` will show all of the ignore conditions of the specified dependency - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself) </details> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
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Summary
Attaching to a
ServiceWorkertarget viaITarget.CreateCDPSessionAsync()and callingDebugger.enableworked fine, butDebugger.scriptParsed(and every other CDP event on that session) never showed up onMessageReceived.Worker-type sessions buffer their early events until
FlushEarlyMessages()is called, to avoid a race where Chrome's init events beat the internal listener's subscription. That flush was only ever wired up for the two internal consumers (CdpWebWorker, blocked service worker registration) —CreateCDPSessionAsync(), the public API, never called it, so every event on a manually-created worker session just piled up in the buffer forever.Wiring the flush into
CreateCDPSessionAsync()exposed a second, separate bug:FlushEarlyMessages()drains the buffer with_messageReceived?.Invoke(this, _bufferedMessages.Dequeue()). When nobody has subscribed yet,?.short-circuits the whole call — including theDequeue()argument — so the queue never actually drains and the loop spins forever. Fixed by dequeuing before the null-conditional invoke.Fixes #3517
Verification
Debugger.getScriptSource; confirmedDebugger.scriptParsednow arrives.ShouldReceiveEventsOnAServiceWorkerSessionCreatedViaCreateCDPSessionAsync— verified it fails without the fix and passes with it.CDPSessionTests,TargetTests,ResponseFromServiceWorkerTests,PageSetBypassServiceWorkerTests(61 tests): passing.🤖 Generated with Claude Code