Function onceAnEvent

test/parallel/test-events-once.js:8–19

()

const assert = require('assert');

async function onceAnEvent() {
  const ee = new EventEmitter();

  process.nextTick(() => {
    ee.emit('myevent', 42);
  });

  const [value] = await once(ee, 'myevent');
  assert.strictEqual(value, 42);
  assert.strictEqual(ee.listenerCount('error'), 0);
  assert.strictEqual(ee.listenerCount('myevent'), 0);
}

async function onceAnEventWithInvalidOptions() {
  const ee = new EventEmitter();