githubmirror/immutable-js

src/utils/isArrayLike.js

18 строк571 B

Lee Byron

Relicence and copyright (#1814)

18 июн 2021, 01:53

18 июн 2021, 01:535155a7f

export default function isArrayLike(value) {
  if (Array.isArray(value) || typeof value === 'string') {
    return true;
  }

  return (
    value &&
    typeof value === 'object' &&
    Number.isInteger(value.length) &&
    value.length >= 0 &&
    (value.length === 0
      ? // Only {length: 0} is considered Array-like.
        Object.keys(value).length === 1
      : // An object is only Array-like if it has a property where the last value
        // in the array-like may be found (which could be undefined).
        value.hasOwnProperty(value.length - 1))
  );
}