require-listener-teardown.md

Requires that listeners be cleaned up on DOM disconnect (require-listener-teardown)

Event listeners should be cleaned up once a component has been removed from DOM to prevent memory leaks.

Rule Details

This rule requires that listeners added in connectedCallback are removed in disconnectedCallback.

The following patterns are considered warnings:

class Foo extends HTMLElement {
  connectedCallback() {
    this.addEventListener('click', this.foo);
  }
}

The following patterns are not warnings:

class Foo extends HTMLElement {
  connectedCallback() {
    this.addEventListener('click', this.foo);
  }
  disconnectedCallback() {
    this.removeEventListener('click', this.foo);
  }
}

When Not To Use It

If you don't care about teardown of listeners, do not use this rule.