Refactor ManifestListItem test to use a createWrapper helper

__tests__/src/components/ManifestListItem.test.js

@@ -2,60 +2,54 @@ import React from 'react';
 import { shallow } from 'enzyme';
 import ManifestListItem from '../../../src/components/ManifestListItem';
 
-describe('ManifestListItem', () => {
-  it('renders without an error', () => {
-    const addWindow = jest.fn();
-    const wrapper = shallow(
+/** */
+function createWrapper(props) {
+  return shallow(
     <ManifestListItem
       manifestId="http://example.com"
       title="xyz"
       ready
-        addWindow={addWindow}
+      addWindow={() => {}}
+      fetchManifest={() => {}}
       t={t => t}
+      {...props}
     />,
-    ).dive();
+  ).dive(); // to unwrapp HOC created by withStyle()
+}
+
+describe('ManifestListItem', () => {
+  it('renders without an error', () => {
+    const wrapper = createWrapper();
     expect(wrapper.find('.mirador-manifest-list-item').length).toBe(1);
     expect(wrapper.find('WithStyles(ButtonBase)').length).toBe(1);
     expect(wrapper.find('WithStyles(ButtonBase) WithStyles(Typography)').children().text()).toEqual('xyz');
   });
   it('renders a placeholder element until real data is available', () => {
-    const addWindow = jest.fn();
-    const wrapper = shallow(
-      <ManifestListItem manifestId="http://example.com" addWindow={addWindow} />,
-    ).dive();
+    const wrapper = createWrapper({ ready: false });
+
     expect(wrapper.find('.mirador-manifest-list-item').length).toBe(1);
     expect(wrapper.find('ReactPlaceholder').length).toBe(1);
   });
   it('updates and adds window when button clicked', () => {
     const addWindow = jest.fn();
-    const wrapper = shallow(
-      <ManifestListItem manifestId="http://example.com" title="xyz" addWindow={addWindow} />,
-    ).dive();
+    const wrapper = createWrapper({ addWindow });
     wrapper.find('WithStyles(ButtonBase)').simulate('click');
     expect(addWindow).toHaveBeenCalledTimes(1);
   });
   it('uses the manifest id if the title is not available', () => {
-    const addWindow = jest.fn();
-    const wrapper = shallow(
-      <ManifestListItem manifestId="http://example.com" ready addWindow={addWindow} />,
-    ).dive();
+    const wrapper = createWrapper({ ready: true, title: null });
+
     expect(wrapper.find('WithStyles(ButtonBase)').length).toBe(1);
     expect(wrapper.find('WithStyles(ButtonBase) WithStyles(Typography)').children().text()).toEqual('http://example.com');
   });
 
   it('displays the provider information', () => {
-    const addWindow = jest.fn();
-    const wrapper = shallow(
-      <ManifestListItem manifestId="http://example.com" ready provider="ACME" addWindow={addWindow} />,
-    ).dive();
+    const wrapper = createWrapper({ provider: 'ACME' });
     expect(wrapper.find('WithStyles(Typography).mirador-manifest-list-item-provider').children().text()).toEqual('ACME');
   });
 
   it('displays a placeholder provider if no information is given', () => {
-    const addWindow = jest.fn();
-    const wrapper = shallow(
-      <ManifestListItem manifestId="http://example.com" ready addWindow={addWindow} />,
-    ).dive();
+    const wrapper = createWrapper();
     expect(wrapper.find('WithStyles(Typography).mirador-manifest-list-item-provider').children().text()).toEqual('addedFromUrl');
   });
 });