fix: memory leak in chatServiceImpl

[Simon Siefke (SimonSiefke)]

Details

Chat follow-up providers create cancellation token sources stored in _sessionFollowupCancelTokens. Disposing a chat session model did not remove and dispose its token source.

Change

The change removes and disposes the matching follow-up cancellation token source when the chat session model is disposed.

Before

When executing a terminal command from chat 37 times, follow-up cancellation token sources and mutable tokens grow across the runs (outlined in red):

After

No more matching cancellation token leak is detected.

Test Video

chat-terminal-command-7-runs.mp4

[Copilot]

Pull request overview

Fixes retained follow-up cancellation token sources when chat sessions are disposed.

Changes:

• Removes and disposes the session’s follow-up token source during model disposal.

[Dmitriy Vasyura (dmitrivMS)]

Simon Siefke (@SimonSiefke) Thank you!

[Dmitriy Vasyura (dmitrivMS)]

Simon Siefke (@SimonSiefke) build errors:
Error: [core-ci ] [00:24:41] src/vs/workbench/contrib/chat/test/common/chatService/chatService.test.ts(663,16): error TS2345: Argument of type '(listener: (e: void) => unknown, thisArgs?: unknown, disposables?: IDisposable[] | undefined) => IDisposable' is not assignable to parameter of type 'Event'.