lodash/test/isRegExp.spec.ts

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

describe('isRegExp', () => {
    it('should return `true` for regexes', () => {
        assert.strictEqual(isRegExp(/x/), true);
        assert.strictEqual(isRegExp(RegExp('x')), true);
    });

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

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

        assert.deepStrictEqual(actual, expected);

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

    it('should work with regexes from another realm', () => {
        if (realm.regexp) {
            assert.strictEqual(isRegExp(realm.regexp), true);
        }
    });
});