Function basic

test/parallel/test-events-on-async-iterator.js:12–37

()

} = require('internal/event_target');

async function basic() {
  const ee = new EventEmitter();
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    // 'bar' is a spurious event, we are testing
    // that it does not show up in the iterable
    ee.emit('bar', 24);
    ee.emit('foo', 42);
  });

  const iterable = on(ee, 'foo');

  const expected = [['bar'], [42]];

  for await (const event of iterable) {
    const current = expected.shift();

    assert.deepStrictEqual(current, event);

    if (expected.length === 0) {
      break;
    }
  }
  assert.strictEqual(ee.listenerCount('foo'), 0);
  assert.strictEqual(ee.listenerCount('error'), 0);
}

async function invalidArgType() {
  assert.throws(() => on({}, 'foo'), common.expectsError({