Cover js component with jasmine test

update

Author: Tu Nguyen

dev/tests/js/jasmine/tests/app/code/Magento/Checkout/frontend/js/view/form/element/email.test.js

@@ -0,0 +1,66 @@
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+/* eslint max-nested-callbacks: 0 */
+
+define(['squire', 'ko'], function (Squire, ko) {
+    'use strict';
+
+    describe('Magento_Checkout/js/view/form/element/email', function () {
+        var injector = new Squire(),
+            mocks = {
+                'Magento_Customer/js/model/customer': {
+                    isLoggedIn: ko.observable()
+                },
+                'Magento_Customer/js/action/check-email-availability': jasmine.createSpy(),
+                'Magento_Customer/js/action/login': jasmine.createSpy(),
+                'Magento_Checkout/js/model/quote': {
+                    isVirtual: jasmine.createSpy(),
+                    shippingAddress: jasmine.createSpy()
+                },
+                'Magento_Checkout/js/checkout-data': jasmine.createSpyObj(
+                    'checkoutData',
+                    [
+                        'setInputFieldEmailValue',
+                        'setValidatedEmailValue',
+                        'setCheckedEmailValue',
+                        'getInputFieldEmailValue',
+                        'getValidatedEmailValue',
+                        'getCheckedEmailValue'
+                    ]
+                ),
+                'Magento_Checkout/js/model/full-screen-loader': jasmine.createSpy(),
+                'mage/validation': jasmine.createSpy()
+            },
+            Component;
+
+        beforeEach(function (done) {
+            injector.mock(mocks);
+            injector.require(['Magento_Checkout/js/view/form/element/email'], function (Constr) {
+                Component = new Constr({
+                    provider: 'provName',
+                    name: '',
+                    index: '',
+                    isPasswordVisible: false,
+                    isEmailCheckComplete: null
+                });
+                done();
+            });
+        });
+
+        afterEach(function () {
+            try {
+                injector.clean();
+                injector.remove();
+            } catch (e) {}
+        });
+
+        describe('"resolveInitialPasswordVisibility" method', function () {
+            it('Check return type of method.', function () {
+                expect(typeof Component.resolveInitialPasswordVisibility()).toEqual('boolean');
+            });
+        });
+    });
+});