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JavaScript Quiz

What happens when one promise in Promise.all rejects?

Do you know what will be the output of this code?

JavaScript 
Promise.all([
  Promise.resolve(1),
  Promise.reject(new Error("fail")),
  Promise.resolve(3),
])
  .then((values) => console.log(values))
  .catch((err) => console.log(err.message));
Show answer and explanation

The answer is "fail".

Promise.all is all-or-nothing: it rejects with the first rejection reason and the fulfilled values are discarded. Promise.allSettled waits for every promise and reports each result.

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