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Promise的构造函数中如果执行同步代码,调用resolve时会立马更新状态吗

Promise的构造函数中如果执行同步代码,调用resolve时会立马更新状态吗,我的理解是resolve是一个微任务,会变更状态,执行then注册的回调,所以在下面的代码中,promise1应该是pending状态,此时调用栈还在执行本轮宏任务,尚未执行微任务,但是在Chrome中,控制台输出的promise1已经是fulfilled。
代码如下:

const promise1 = new Promise((resolve, reject) => {
  console.log('promise1');
  resolve('resolve1');
})

const promise2 = promise1.then((res) => {
  console.log(res);
});

console.log('1', promise1);
console.log('2', promise2);

Chrome中结果如下:
image.png


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by (71.8m points)

更新状态不意味就立马要去执行回调。状态是在微任务期间判断是否执行该回调的依据


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