text: import * as assert from '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(_), 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);
      }
    });
  });
  