wip: code formatting nits continued

test/isElement.spec.js

@@ -0,0 +1,56 @@
+import lodashStable from 'lodash';
+import { document, body, falsey, stubFalse, args, slice, symbol, realm } from './utils';
+import isElement from '../src/isElement';
+
+describe('isElement', () => {
+    it('should return `true` for elements', () => {
+        if (document) {
+            expect(isElement(body)).toBe(true);
+        }
+    });
+
+    it('should return `true` for non-plain objects', () => {
+        function Foo() {
+            this.nodeType = 1;
+        }
+
+        expect(isElement(new Foo())).toBe(true);
+    });
+
+    it('should return `false` for non DOM elements', () => {
+        const expected = lodashStable.map(falsey, stubFalse);
+
+        const actual = lodashStable.map(falsey, (value, index) =>
+            index ? isElement(value) : isElement(),
+        );
+
+        expect(actual).toEqual(expected);
+
+        expect(isElement(args)).toBe(false);
+        expect(isElement([1, 2, 3])).toBe(false);
+        expect(isElement(true)).toBe(false);
+        expect(isElement(new Date())).toBe(false);
+        expect(isElement(new Error())).toBe(false);
+        expect(isElement(slice)).toBe(false);
+        expect(isElement({ a: 1 })).toBe(false);
+        expect(isElement(1)).toBe(false);
+        expect(isElement(/x/)).toBe(false);
+        expect(isElement('a')).toBe(false);
+        expect(isElement(symbol)).toBe(false);
+    });
+
+    it('should return `false` for plain objects', () => {
+        expect(isElement({ nodeType: 1 })).toBe(false);
+        expect(isElement({ nodeType: Object(1) })).toBe(false);
+        expect(isElement({ nodeType: true })).toBe(false);
+        expect(isElement({ nodeType: [1] })).toBe(false);
+        expect(isElement({ nodeType: '1' })).toBe(false);
+        expect(isElement({ nodeType: '001' })).toBe(false);
+    });
+
+    it('should work with a DOM element from another realm', () => {
+        if (realm.element) {
+            expect(isElement(realm.element)).toBe(true);
+        }
+    });
+});