memory-leak-audit Skill

Source

• Creator: microsoft
• Repository: microsoft/vscode
• Skill file: .github/skills/memory-leak-audit/SKILL.md

What it does

Audit code for memory leaks and disposable issues. Use when reviewing event listeners, DOM handlers, lifecycle callbacks, or fixing leak reports. Covers addDisposableListener, Event.once, MutableDisposable, DisposableStore, and onWillDispose patterns.

Skill instructions

Memory Leak Audit The 1 bug category in VS Code. This skill encodes the patterns that prevent and fix leaks. When to Use - Reviewing code that registers event listeners or DOM handlers - Fixing reported memory leaks (listener counts growing over time) - Creating objects in methods that are called repeatedly - Working with model lifecycle events (onWillDispose, onDidClose) - Adding event subscriptions in constructors or setup methods Audit Checklist Work through each check in order. A single missed pattern can cause thousands of leaked objects. Step 1: DOM Event Listeners Rule: Never use raw .onload, .onclick, or addEventListener() directly. Always use addDisposableListener(). typescript // BAD — leaks a listener every call this.iconElement.onload = () = { ... }; // GOOD — tracked and disposable this.register(addDisposableListener(this.iconElement, 'load', () = { ... })); Validated by: PR 280566 — Extension icon widget leaked 185 listeners after 37 toggles. Step 2: One-Time Events Rule: