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