iter-tools-es/impls/$deep-equal/async-deep-equal.js

The iterable toolbox

const {
  asyncIsIterable,
  asyncIsWrappable
} = require('../../internal/async-iterable.js');

const {
  __map
} = require('../$map/map.js');

const {
  __every
} = require('../$every/every.js');

const {
  __asyncZipAll
} = require('../$zip-all/async-zip-all.js');

const {
  __sliceFromStart
} = require('../$slice/slice.js');

const none = Symbol('none');
const zipAllConfig = {
  filler: none
};

const asyncEmpty = async function* () {};

const asyncIterableOrEmpty = value => value == null ? asyncEmpty() : value;

async function _asyncDeepEqual(values, same, isIterable, depth = 0) {
  if (__every(values, value => typeof value !== 'string' && isIterable(value))) {
    for await (const stepValues of __asyncZipAll(__map(values, asyncIterableOrEmpty), zipAllConfig)) {
      if (!(await _asyncDeepEqual(stepValues, same, isIterable, depth + 1))) return false;
    }
  } else {
    const firstValue = values[0];

    for (const value of __sliceFromStart(values, 1)) {
      if (!same(value, firstValue, depth)) return false;
    }
  }

  return true;
}

exports._asyncDeepEqual = _asyncDeepEqual;

function __asyncDeepEqual(values, same = Object.is, coerceNil = true) {
  return values.length <= 1 ? true : _asyncDeepEqual(values, same, coerceNil ? asyncIsWrappable : asyncIsIterable);
}

exports.__asyncDeepEqual = __asyncDeepEqual;

function asyncDeepEqual(...values) {
  return __asyncDeepEqual(values);
}

exports.asyncDeepEqual = asyncDeepEqual;