Add index spec

spec/javascripts/repo/index_spec.js

+import Tabs from '~/repo/repo_tabs';
+import Sidebar from '~/repo/repo_sidebar';
+import Editor from '~/repo/repo_editor';
+import FileButtons from '~/repo/repo_file_buttons';
+import EditButton from '~/repo/repo_edit_button';
+import BinaryViewer from '~/repo/repo_binary_viewer';
+import CommitSection from '~/repo/repo_commit_section';
+import Service from '~/repo/repo_service';
+import Store from '~/repo/repo_store';
+import Helper from '~/repo/repo_helper';
+
+describe('initRepo', () => {
+  const url = 'url';
+
+  it('should select all elements, set store service and url, init all needed classes and getContent', () => {
+    spyOn(Helper, 'getContent');
+    spyOn(document, 'getElementById').and.callFake((selector) => {
+      const element = document.createElement('div');
+
+      if (selector === 'ide') element.dataset.url = url;
+
+      return element;
+    });
+
+    require('~/repo/index'); // eslint-disable-line global-require
+
+    expect(document.getElementById).toHaveBeenCalledWith('ide');
+    expect(document.getElementById).toHaveBeenCalledWith('tabs');
+    expect(document.getElementById).toHaveBeenCalledWith('sidebar');
+    expect(document.getElementById).toHaveBeenCalledWith('repo-file-buttons');
+    expect(document.getElementById).toHaveBeenCalledWith('editable-mode');
+    expect(document.getElementById).toHaveBeenCalledWith('commit-area');
+    expect(document.getElementById).toHaveBeenCalledWith('binary-viewer');
+    expect(Store.service).toBe(Service);
+    expect(Store.service.url).toBe(url);
+    expect(Store.tabs instanceof Tabs).toBe(true);
+    expect(Store.sidebar instanceof Sidebar).toBe(true);
+    expect(Store.editor instanceof Editor).toBe(true);
+    expect(Store.buttons instanceof FileButtons).toBe(true);
+    expect(Store.editButton instanceof EditButton).toBe(true);
+    expect(Store.commitSection instanceof CommitSection).toBe(true);
+    expect(Store.binaryViewer instanceof BinaryViewer).toBe(true);
+    expect(Helper.getContent).toHaveBeenCalled();
+  });
+});