chained-promises.js

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// Flags: --expose-async-hooks

// Check for chained promises asyncIds relation
(function() {
  let asyncIds = [], triggerIds = [];
  let ah = async_hooks.createHook({
    init(asyncId, type, triggerAsyncId, resource) {
      asyncIds.push(asyncId);
      triggerIds.push(triggerAsyncId);
    },
  });
  ah.enable();
  let createdPromise = new Promise(function(resolve) {
    resolve(42);
  }).then(function() {
    assertEquals(3, asyncIds.length, 'Exactly 3 promises should be inited');
    assertEquals(3, triggerIds.length, 'Exactly 3 promises should be inited');
    assertEquals(triggerIds[1], asyncIds[0],
      "Parent promise asyncId doesn't correspond to child triggerAsyncId");
  }).catch((err) => {
    setTimeout(() => {
      throw err;
    }, 0);
  });
})();