wip: code formatting nits continued

test/isMap.spec.js

@@ -0,0 +1,47 @@
+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) {
+            expect(isMap(map)).toBe(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()));
+
+        expect(actual).toEqual(expected);
+
+        expect(isMap(args)).toBe(false);
+        expect(isMap([1, 2, 3])).toBe(false);
+        expect(isMap(true)).toBe(false);
+        expect(isMap(new Date())).toBe(false);
+        expect(isMap(new Error())).toBe(false);
+        expect(isMap(slice)).toBe(false);
+        expect(isMap({ a: 1 })).toBe(false);
+        expect(isMap(1)).toBe(false);
+        expect(isMap(/x/)).toBe(false);
+        expect(isMap('a')).toBe(false);
+        expect(isMap(symbol)).toBe(false);
+        expect(isMap(weakMap)).toBe(false);
+    });
+
+    it('should work for objects with a non-function `constructor` (test in IE 11)', () => {
+        const values = [false, true];
+        const expected = lodashStable.map(values, stubFalse);
+
+        const actual = lodashStable.map(values, (value) => isMap({ constructor: value }));
+
+        expect(actual).toEqual(expected);
+    });
+
+    it('should work with maps from another realm', () => {
+        if (realm.map) {
+            expect(isMap(realm.map)).toBe(true);
+        }
+    });
+});