core-js/tests/unit-pure/esnext.array.group-by-to-map.js

import { STRICT } from '../helpers/constants.js';

import Map from 'core-js-pure/es/map';
import Symbol from 'core-js-pure/es/symbol';
import from from 'core-js-pure/es/array/from';
import groupByToMap from 'core-js-pure/actual/array/group-by-to-map';

QUnit.test('Array#groupByToMap', assert => {
  assert.isFunction(groupByToMap);
  let array = [1];
  const context = {};
  groupByToMap(array, function (value, key, that) {
    assert.same(arguments.length, 3, 'correct number of callback arguments');
    assert.same(value, 1, 'correct value in callback');
    assert.same(key, 0, 'correct index in callback');
    assert.same(that, array, 'correct link to array in callback');
    assert.same(this, context, 'correct callback context');
  }, context);
  assert.true(groupByToMap([], it => it) instanceof Map, 'returns Map');
  assert.deepEqual(from(groupByToMap([1, 2, 3], it => it % 2)), [[1, [1, 3]], [0, [2]]], '#1');
  assert.deepEqual(
    from(groupByToMap([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12], it => `i${ it % 5 }`)),
    [['i1', [1, 6, 11]], ['i2', [2, 7, 12]], ['i3', [3, 8]], ['i4', [4, 9]], ['i0', [5, 10]]],
    '#2',
  );
  assert.deepEqual(from(groupByToMap(Array(3), it => it)), [[undefined, [undefined, undefined, undefined]]], '#3');
  if (STRICT) {
    assert.throws(() => groupByToMap(null, () => { /* empty */ }), TypeError, 'null this -> TypeError');
    assert.throws(() => groupByToMap(undefined, () => { /* empty */ }), TypeError, 'undefined this -> TypeError');
  }
  array = [1];
  // eslint-disable-next-line object-shorthand -- constructor
  array.constructor = { [Symbol.species]: function () {
    return { foo: 1 };
  } };
  assert.same(groupByToMap(array, Boolean).get(true).foo, undefined, 'no @@species');
});