import assert from 'node:assert'; import lodashStable from 'lodash'; import { falsey, args, slice, symbol, realm } from './utils'; import isBoolean from '../src/isBoolean'; describe('isBoolean', () => { it('should return `true` for booleans', () => { assert.strictEqual(isBoolean(true), true); assert.strictEqual(isBoolean(false), true); assert.strictEqual(isBoolean(Object(true)), true); assert.strictEqual(isBoolean(Object(false)), true); }); it('should return `false` for non-booleans', () => { const expected = lodashStable.map(falsey, (value) => value === false); const actual = lodashStable.map(falsey, (value, index) => index ? isBoolean(value) : isBoolean(), ); assert.deepStrictEqual(actual, expected); assert.strictEqual(isBoolean(args), false); assert.strictEqual(isBoolean([1, 2, 3]), false); assert.strictEqual(isBoolean(new Date()), false); assert.strictEqual(isBoolean(new Error()), false); assert.strictEqual(isBoolean(slice), false); assert.strictEqual(isBoolean({ a: 1 }), false); assert.strictEqual(isBoolean(1), false); assert.strictEqual(isBoolean(/x/), false); assert.strictEqual(isBoolean('a'), false); assert.strictEqual(isBoolean(symbol), false); }); it('should work with a boolean from another realm', () => { if (realm.boolean) { assert.strictEqual(isBoolean(realm.boolean), true); } }); });