fix: memory leak in extension host pseudoterminals

[Simon Siefke (SimonSiefke)]

Details

Closing an extension-owned terminal removes the terminal API object, but process cleanup only runs from the pseudoterminal's onDidClose event. A pseudoterminal does not have to provide that event, so its process entry, buffered-data subscription, and event listeners remain after the terminal closes.

Change

Run process cleanup from both the terminal-close path and the process-exit path. Include the pseudoterminal, its event subscriptions, and the data-buffer subscription in the process disposable, and skip listener setup if the terminal closed before setup completed.

Before

When creating and disposing an extension pseudoterminal 37 times, the pseudoterminal, terminal API object, and callbacks grow each time:

After

No more extension host pseudoterminal leak is detected.

Test Video

go-progress-terminal.webm

[Copilot]

Pull request overview

Fixes extension-host pseudoterminal resource leaks during terminal closure and process exit.

Changes:

• Tracks pseudoterminal listeners and buffered-data subscriptions for disposal.
• Cleans process resources from both closure paths.
• Adds regression coverage for terminal-close cleanup.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
extHostTerminalService.ts	Adds pseudoterminal lifecycle cleanup.
extHostTerminalService.test.ts	Tests cleanup after terminal closure.

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[Megan Rogge (meganrogge)]

Thank you!