Fix memory leak in AutoRepliesPtyServiceContribution on process dispose

[winjo]

The problem

AutoRepliesPtyServiceContribution.handleProcessDispose only clears the inner per-process Map<string, TerminalAutoResponder> of _autoResponders. It never removes the key from the outer _autoResponders map, and it never removes the corresponding entry from _terminalProcesses.

ptyService calls handleProcessDispose(id) on every TerminalProcess's onProcessExit, so both maps grow monotonically for the lifetime of the pty host. Each leaked entry keeps a TerminalProcess → UnixTerminal → _socket (ReadStream) chain alive, which in turn keeps the pipe/pty file descriptors and their kernel read buffers allocated.

How it shows up

• JS heap snapshot comparison between two pty-host snapshots shows near-zero JS heap delta, but a steady stream of extra ReadStream, TerminalProcess, UnixTerminal, and ArrayBuffer/Uint32Array instances.
• ps RSS for the pty host grows by tens of MiB after a batch of spawned-then-exited terminals (we observed +70 MiB after a single task that spawned a few dozen pty-backed child processes).
• In DevTools → Memory, the retainer chain of a leaked ReadStream reliably walks back to _terminalProcesses on an AutoRepliesPtyServiceContribution instance held by PtyService.

The fix

Add the two missing delete calls at the end of handleProcessDispose, unconditionally (they must run even when _autoResponders has no entry for the id, so they sit outside the existing if block).

this._autoResponders.delete(persistentProcessId);
this._terminalProcesses.delete(persistentProcessId);

After the fix, _terminalProcesses.size and _autoResponders.size track the number of live ptys, and the native fd/buffer memory is released as soon as the process exits.

How to verify

1. Open a pty host heap snapshot before and after spawning & closing a batch of terminals.
2. Comparison view: before the fix, ReadStream / TerminalProcess / UnixTerminal have # Deleted = 0; after the fix, # New ≈ # Deleted.
3. ps -o rss= <pty-host-pid> stops climbing proportionally to the number of closed terminals.

[vs-code-engineering]

📬 CODENOTIFY

The following users are being notified based on files changed in this PR:

@anthonykim1

Matched files:

• src/vs/platform/terminal/node/terminalContrib/autoReplies/autoRepliesContribController.ts