在Javascript中,为什么{a:1} == {a:1}会出错,({a:1})== {a:1}会有效吗？

function objectsAreEqual(obj1, obj2) {
  const keys1 = Object.keys(obj1);
  const keys2 = Object.keys(obj2);

  if (keys1.length !== keys2.length) {
    return false;
  }

  for (const key of keys1) {
    if (!obj2.hasOwnProperty(key) || obj1[key] !== obj2[key]) {
      return false;
    }
  }

  return true;
}

const obj1 = {a: 1};
const obj2 = {a: 1};

console.log(objectsAreEqual(obj1, obj2)); // 输出：true