Cover changes with jasmnine test

Author: Nazar65

dev/tests/js/jasmine/tests/app/code/Magento/Ui/base/js/grid/columns/image-preview.test.js

@@ -0,0 +1,50 @@
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+/* eslint-disable max-nested-callbacks, no-undef */
+
+define([
+    'Magento_Ui/js/grid/columns/image-preview',
+    'ko',
+    'jquery'
+], function (Preview, ko, $) {
+    'use strict';
+
+    describe('Ui/js/grid/columns/image-preview', function () {
+        var record = {
+            _rowIndex: 1,
+            rowNumber: 1
+        },
+           imagePreview;
+
+        beforeEach(function () {
+            imagePreview = new Preview();
+
+            /**
+             * @return {Object}
+             */
+            function getThumbnail()  {
+                return {
+                    previewRowId: ko.observable()
+                };
+            }
+
+            imagePreview.thumbnailComponent = getThumbnail;
+
+            imagePreview.visibleRecord = ko.observable(1);
+        });
+
+        describe('show method', function () {
+            it('show image', function () {
+                var mockImg = document.createElement('img'),
+                    hide = spyOn(imagePreview, 'hide');
+
+                spyOn($.fn, 'get').and.returnValue(mockImg);
+                imagePreview.show(record);
+                expect(hide).toHaveBeenCalledTimes(1);
+            });
+
+        });
+    });
+});