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Xb Testing

google/xb-testing

>- Write sequential asynchronous functional, integration, or simulator tests for xrblocks apps using the testing addon. Use this when you need to mock WebGL/WebAudio in headless environments (like JSDOM / Vitest), simulate user locomotion, trigger controller pointing, raycasts, and select/squeeze hand inputs. Covers `TestRunner` and `TestRunnerConfig`.

750 tokens
context cost
the whole folder, loaded on every use
1
files
instructions only
0
copies elsewhere
how many repositories repackaged it
455
stars on the repo
on the repository, not the skill itself

Install

one command, takes just this skill from the repository 
npx skills add https://github.com/google/xrblocks --skill xb-testing

The instruction itself

6 sections, as written by the author

xb-testing: functional & simulator testing

The testing addon (import { TestRunner } from 'xrblocks/addons/testing') provides a headless functional test framework designed to test scripts, locomotion, interaction, and engine lifecycle sequentially under environments like Vitest/JSDOM.

Bootstrapping a test

Use TestRunner.create to spin up a core instance with a spied canvas/WebGL context:

import {describe, it, expect} from 'vitest';
import {TestRunner} from 'xrblocks/addons/testing';
import {MyScript} from './MyScript';

describe('My Functional Test', () => {
  it('verifies script interaction', async () => {
    const script = new MyScript();

    // Create the runner and load scripts
    const runner = await TestRunner.create({
      scripts: [script],
    });

    // Step the frame loop forward (in milliseconds)
    await runner.step(100);

    // Check script states
    expect(script.someValue).toBe(true);

    // Always clean up to prevent memory/state leaks
    await runner.destroy();
  });
});

Locomotion (movement)

Simulate user camera translation (in strafe, rise, forward offsets relative to camera orientation):

// Move user forward by 1 meter
await runner.move([0, 0, -1], {durationMs: 200});

// Verify camera position changed
expect(runner.camera.position.z).toBeLessThan(0);

Pointer & click interactions

Simulate hands or controllers pointing at objects and performing selections (pinches/clicks):

// Point right hand (index 1) directly at the target object
await runner.pointTo(1, targetMesh);

// Perform a pinch/click with the right hand
await runner.click(1);

// Step time in ms to allow the select start and select end callbacks to fire
await runner.step(250);

expect(targetMesh.clicked).toBe(true);

Error handling

Any error or exception thrown during script lifecycle (init, update, onSelectEnd, etc.) is caught by the test runner. Call step() or check for errors explicitly:

// Script crash verification
const crasher = new CrashingScript();
const runner = await TestRunner.create({scripts: [crasher]});

// Advancing the frame loop throws the exception caught in the script
await expect(runner.step(16.67)).rejects.toThrow(
  'Script crash inside update loop'
);

Notes

  • Auto-mocking: TestRunner automatically stubs AudioContext, AudioListener parameter curves, and WebGLRenderer capabilities transparently.
  • Teardown: Always call await runner.destroy() in your tests to reset the core singleton, otherwise subsequent tests will share state and leak listeners.

How to use it

Copy the folder

Take google/xb-testing from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.