let callbacks = []; export default { props: { callback: (value) => callbacks.push(value), val1: "1", val2: "2" }, before_test() { callbacks = []; }, async test({ assert, component, target }) { assert.equal(callbacks.length, 2); assert.equal(JSON.stringify(callbacks), '["1","2"]'); component.val1 = "3"; assert.equal(callbacks.length, 3); assert.equal(JSON.stringify(callbacks), '["1","2","1"]'); component.val1 = "4"; assert.equal(callbacks.length, 4); assert.equal(JSON.stringify(callbacks), '["1","2","1","1"]'); component.val2 = "5"; assert.equal(callbacks.length, 5); assert.equal(JSON.stringify(callbacks), '["1","2","1","1","2"]'); } };