Adds unit tests for discussion component

app/assets/javascripts/notes/components/issue_discussion.vue

@@ -179,7 +179,7 @@
                     v-if="canReply && !isReplying"
                     @click="showReplyForm"
                     type="button"
-                    class="btn btn-text-field"
+                    class="js-vue-discussion-reply btn btn-text-field"
                     title="Add a reply">Reply...</button>
                   <issue-note-form
                     v-if="isReplying"

spec/javascripts/notes/components/issue_discussion_spec.js

+import Vue from 'vue';
+import store from '~/notes/stores';
+import issueDiscussion from '~/notes/components/issue_discussion.vue';
+import { issueDataMock, discussionMock, notesDataMock } from '../mock_data';
 
 describe('issue_discussion component', () => {
-  it('should render user avatar', () => {
-  });
-
-  it('should render discussion header', () => {
+  let vm;
 
-  });
+  beforeEach(() => {
+    const Component = Vue.extend(issueDiscussion);
 
-  describe('updated note', () => {
-    it('should show information about update', () => {
+    store.dispatch('setIssueData', issueDataMock);
+    store.dispatch('setNotesData', notesDataMock);
 
-    });
+    vm = new Component({
+      store,
+      propsData: {
+        note: discussionMock,
+      },
+    }).$mount();
   });
 
-  describe('with open discussion', () => {
-    it('should render system note', () => {
-
+  afterEach(() => {
+    vm.$destroy();
   });
 
-    it('should render placeholder note', () => {
-
+  it('should render user avatar', () => {
+    expect(vm.$el.querySelector('.user-avatar-link')).toBeDefined();
   });
 
-    it('should render regular note', () => {
-
+  it('should render discussion header', () => {
+    expect(vm.$el.querySelector('.discussion-header')).toBeDefined();
+    expect(vm.$el.querySelectorAll('.notes li').length).toEqual(discussionMock.notes.length);
   });
 
   describe('actions', () => {
     it('should render reply button', () => {
-
+      expect(vm.$el.querySelector('.js-vue-discussion-reply').textContent.trim()).toEqual('Reply...');
     });
 
-      it('should toggle reply form', () => {
-
-      });
-
-      it('should render signout widget when user is logged out', () => {
-
+    it('should toggle reply form', (done) => {
+      vm.$el.querySelector('.js-vue-discussion-reply').click();
+      Vue.nextTick(() => {
+        expect(vm.$refs.noteForm).toBeDefined();
+        expect(vm.isReplying).toEqual(true);
+        done();
       });
     });
   });