lodash/test/mapValues.spec.ts

import assert from 'node:assert';
import lodashStable from 'lodash';
import mapValues from '../src/mapValues';

describe('mapValues', () => {
    const array = [1, 2],
        object = { a: 1, b: 2 };

    it('should map values in `object` to a new object', () => {
        const actual = mapValues(object, String);
        assert.deepStrictEqual(actual, { a: '1', b: '2' });
    });

    it('should treat arrays like objects', () => {
        const actual = mapValues(array, String);
        assert.deepStrictEqual(actual, { '0': '1', '1': '2' });
    });

    it('should work with `_.property` shorthands', () => {
        const actual = mapValues({ a: { b: 2 } }, 'b');
        assert.deepStrictEqual(actual, { a: 2 });
    });

    it('should use `_.identity` when `iteratee` is nullish', () => {
        const object = { a: 1, b: 2 },
            values = [, null, undefined],
            expected = lodashStable.map(values, lodashStable.constant([true, false]));

        const actual = lodashStable.map(values, (value, index) => {
            const result = index ? mapValues(object, value) : mapValues(object);
            return [lodashStable.isEqual(result, object), result === object];
        });

        assert.deepStrictEqual(actual, expected);
    });
});