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Promise.allSettled Polyfill

MediumP2Coding

Implement promiseAllSettled(promises), a polyfill for Promise.allSettled.

It takes an iterable of values or promises and returns a promise that never rejects. After every input has settled it resolves with an array, in input order, of result objects:

  • { status: 'fulfilled', value } for an input that resolved (plain values count as resolved),
  • { status: 'rejected', reason } for an input that rejected.

An empty input resolves with []. Do not call Promise.allSettled.

Example 1

Input
promiseAllSettled([Promise.resolve(1), Promise.reject('no')])
Output
[{ status: 'fulfilled', value: 1 }, { status: 'rejected', reason: 'no' }]

Constraints

  • 0 <= number of items <= 10^4

Hints

Run checks the 3 visible tests, Submit all 8.