export default { html: '', props: { foo: 42 }, test({ assert, component, target, window }) { const event = new window.MouseEvent('click'); const button = target.querySelector('button'); let count = 0; let number = null; component.$on('foo', event => { count++; number = event.detail.foo; }); button.dispatchEvent(event); assert.equal(count, 1); assert.equal(number, 42); } };