Add tests for defer destroy in ShaeWorkerElement

[Copilot]

Addresses the TODO comment requesting tests for the #deferDestroy() mechanism in ShaeWorkerElement. Also fixes a bug discovered during test development where reconnecting an already-started element wouldn't cancel pending destruction.

Changes

• New test file ShaeWorkerElement.spec.ts

  • Verifies destruction is deferred via microtask (not synchronous)
  • Verifies reconnection before microtask cancels pending destruction
  • Verifies destruction completes when element stays disconnected
  • Verifies only one destruction is scheduled per disconnect

• Bug fix in start() method

  • Moved #shouldDestroy = false outside the if (!this.#started) block
  • Previously, reconnecting an already-started element wouldn't reset the flag, causing destruction to proceed despite reconnection

// Before: only reset on first start
start(): Promise<ShadowEnv> {
  if (!this.#started) {
    this.#shouldDestroy = false;
    // ...
  }
}

// After: reset on every start (including reconnection)
start(): Promise<ShadowEnv> {
  this.#shouldDestroy = false;
  if (!this.#started) {
    // ...
  }
}

• Cleanup
  • Removed TODO(test) comment
  • Updated TODO.md

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• accounts.google.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=6108 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/tmp/puppeteer_dev_chrome_profile-J2P81F --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,7393353015857758025,2173936733136109263,262144 --enable-features=PdfOopif --disable-features=AcceptCHFrame,IsolateSandboxedIframes,MediaRouter,OptimizationHints,PaintHolding,ProcessPerSiteUpToMainFrameThreshold,Translate --variations-seed-version --trace-process-track-uuid=3190708989122997041 (dns block)
  • Triggering command: /opt/google/chrome/chrome /usr/bin/google-chrome-stable --allow-pre-commit-input --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-hang-monitor --disable-infobars --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-search-engine-choice-screen --disable-sync (dns block)
• clients2.google.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=6108 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/tmp/puppeteer_dev_chrome_profile-J2P81F --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,7393353015857758025,2173936733136109263,262144 --enable-features=PdfOopif --disable-features=AcceptCHFrame,IsolateSandboxedIframes,MediaRouter,OptimizationHints,PaintHolding,ProcessPerSiteUpToMainFrameThreshold,Translate --variations-seed-version --trace-process-track-uuid=3190708989122997041 (dns block)
  • Triggering command: /opt/google/chrome/chrome /usr/bin/google-chrome-stable --allow-pre-commit-input --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-hang-monitor --disable-infobars --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-search-engine-choice-screen --disable-sync (dns block)
• safebrowsingohttpgateway.googleapis.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=6108 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/tmp/puppeteer_dev_chrome_profile-J2P81F --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,7393353015857758025,2173936733136109263,262144 --enable-features=PdfOopif --disable-features=AcceptCHFrame,IsolateSandboxedIframes,MediaRouter,OptimizationHints,PaintHolding,ProcessPerSiteUpToMainFrameThreshold,Translate --variations-seed-version --trace-process-track-uuid=3190708989122997041 (dns block)
  • Triggering command: /opt/google/chrome/chrome /usr/bin/google-chrome-stable --allow-pre-commit-input --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-hang-monitor --disable-infobars --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-search-engine-choice-screen --disable-sync (dns block)
• www.google.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=6108 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/tmp/puppeteer_dev_chrome_profile-J2P81F --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,7393353015857758025,2173936733136109263,262144 --enable-features=PdfOopif --disable-features=AcceptCHFrame,IsolateSandboxedIframes,MediaRouter,OptimizationHints,PaintHolding,ProcessPerSiteUpToMainFrameThreshold,Translate --variations-seed-version --trace-process-track-uuid=3190708989122997041 (dns block)
  • Triggering command: /opt/google/chrome/chrome /usr/bin/google-chrome-stable --allow-pre-commit-input --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-hang-monitor --disable-infobars --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-search-engine-choice-screen --disable-sync (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Work on TODO: add tests for defer destroy (from packages/shadow-objects/src/elements/ShaeWorkerElement.ts)

Created from VS Code via the GitHub Pull Request extension.

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