fix: memory leak in pane composite bar

[SimonSiefke]

Fixes a memory leak in paneCompositeBar.

It seems the paneCompositeBar can be visible for a longer period of time, while it's actions can update many times.

private getCompositeActions(){
  // composite actions are updated, but the already registered ones not disposed here
  this.compositeActions.set(compositeId, compositeActions)
}

By changing the code to use a DisposableMap, it ensures that the previous actions are disposed when the actions are updated.

Before

When renaming a variable 97 times with refactor preview, it seems 3 actions are created each time:

After

When renaming a variable 97 times with refactor preview, no more action leaks are detected:

[vs-code-engineering]

📬 CODENOTIFY

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

@bpasero

Matched files:

• src/vs/workbench/browser/parts/paneCompositeBar.ts

[Copilot]

Pull request overview

This PR fixes a disposable leak in the workbench PaneCompositeBar by ensuring per-composite actions are properly lifecycle-managed when composites are hidden/removed and later re-created.

Changes:

• Replace the compositeActions cache from a plain Map to a _register’d DisposableMap so cached action bundles are disposed when replaced/removed.
• Stop _register’ing individual composite actions into the long-lived PaneCompositeBar store; instead dispose them via the map entry’s dispose().
• Ensure all three actions (activityAction, pinnedAction, and badgeAction) are disposed when a composite is hidden/removed.

---

You can also share your feedback on Copilot code review. Take the survey.

[Copilot]

Copilot's findings

Comments suppressed due to low confidence (1)

src/vs/workbench/browser/parts/paneCompositeBar.ts:335

• In the placeholder branch, toCompositeBarActionItem(...) is computed inline while constructing the activity action. If options.icon is enabled and the icon is a URI, this can also insert CSS rules; keeping it in a local actionItem avoids accidental repeated computation if this block is refactored/extended and keeps the pattern consistent with the non-placeholder branch.

			}

			const disposable = combinedDisposable(activityAction, pinnedAction, badgeAction);
			compositeActions = { activityAction, pinnedAction, badgeAction, dispose: () => disposable.dispose() };
			this.compositeActions.set(compositeId, compositeActions);
		}

		return compositeActions;
	}

• Files reviewed: 1/1 changed files
• Comments generated: 1

[dmitrivMS]

@SimonSiefke Thank you!

[Copilot]

Copilot's findings

• Files reviewed: 1/1 changed files
• Comments generated: 0 new