lodash/test/isMap.spec.ts

import assert from 'node:assert';
import lodashStable from 'lodash';
import { map, falsey, stubFalse, args, slice, symbol, weakMap, realm } from './utils';
import isMap from '../src/isMap';

describe('isMap', () => {
    it('should return `true` for maps', () => {
        if (Map) {
            assert.strictEqual(isMap(map), true);
        }
    });

    it('should return `false` for non-maps', () => {
        const expected = lodashStable.map(falsey, stubFalse);

        const actual = lodashStable.map(falsey, (value, index) => (index ? isMap(value) : isMap()));

        assert.deepStrictEqual(actual, expected);

        assert.strictEqual(isMap(args), false);
        assert.strictEqual(isMap([1, 2, 3]), false);
        assert.strictEqual(isMap(true), false);
        assert.strictEqual(isMap(new Date()), false);
        assert.strictEqual(isMap(new Error()), false);
        assert.strictEqual(isMap(slice), false);
        assert.strictEqual(isMap({ a: 1 }), false);
        assert.strictEqual(isMap(1), false);
        assert.strictEqual(isMap(/x/), false);
        assert.strictEqual(isMap('a'), false);
        assert.strictEqual(isMap(symbol), false);
        assert.strictEqual(isMap(weakMap), false);
    });

    it('should work for objects with a non-function `constructor` (test in IE 11)', () => {
        const values = [false, true],
            expected = lodashStable.map(values, stubFalse);

        const actual = lodashStable.map(values, (value) => isMap({ constructor: value }));

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

    it('should work with maps from another realm', () => {
        if (realm.map) {
            assert.strictEqual(isMap(realm.map), true);
        }
    });
});