Create specs for comments messages in diffs/appstash-spec-helpers-mock-vuex-module

- This component was missing unit tests
  https://gitlab.com/gitlab-org/gitlab-ce/issues/48034
- The comments message behavior will be updated to resolve
  https://gitlab.com/gitlab-org/gitlab-ce/issues/49329

3 files changed, 94 insertions, 1 deletions

diff --git a/app/assets/javascripts/diffs/store/modules/diff_state.js b/app/assets/javascripts/diffs/store/modules/diff_state.js
index 39d90a64aab..eb596b251c1 100644
--- a/app/assets/javascripts/diffs/store/modules/diff_state.js
+++ b/app/assets/javascripts/diffs/store/modules/diff_state.js
@@ -11,8 +11,10 @@ export default () => ({
   endpoint: '',
   basePath: '',
   commit: null,
+  startVersion: null,
   diffFiles: [],
   mergeRequestDiffs: [],
+  mergeRequestDiff: null,
   diffLineCommentForms: {},
   diffViewType: viewTypeFromQueryString || viewTypeFromCookie || defaultViewType,
 });
diff --git a/spec/javascripts/diffs/components/app_spec.js b/spec/javascripts/diffs/components/app_spec.js
index 7237274eb43..0757e926666 100644
--- a/spec/javascripts/diffs/components/app_spec.js
+++ b/spec/javascripts/diffs/components/app_spec.js
@@ -1 +1,76 @@
-// TODO: https://gitlab.com/gitlab-org/gitlab-ce/issues/48034
+import Vue from 'vue';
+import App from '~/diffs/components/app.vue';
+import { mountComponentWithStore } from 'spec/helpers/vue_mount_component_helper';
+import { TEST_HOST } from 'spec/test_constants';
+import createMockStore from '../create_mock_store';
+
+const TEST_ENDPOINT = `${TEST_HOST}/diff/endpoint`;
+const TEST_PROJECT_PATH = 'namespace/project';
+
+describe('diffs App', () => {
+  const Component = Vue.extend(App);
+  const oldMrTabs = window.mrTabs;
+
+  let vm;
+
+  beforeEach(() => {
+    // --- setup globals ---
+    window.mrTabs = jasmine.createSpyObj('mrTabs', ['resetViewContainer']);
+
+    // --- setup component ---
+    const store = createMockStore();
+    store.state.diffs.isLoading = false;
+
+    vm = mountComponentWithStore(Component, {
+      store,
+      props: {
+        endpoint: TEST_ENDPOINT,
+        projectPath: TEST_PROJECT_PATH,
+        currentUser: {},
+      },
+    });
+  });
+
+  afterEach(() => {
+    // --- reset globals ---
+    window.mrTabs = oldMrTabs;
+
+    // --- reset component ---
+    vm.$destroy();
+  });
+
+  it('shows comments message, with commit', done => {
+    vm.$store.state.diffs.commit = {};
+
+    vm.$nextTick()
+      .then(() => {
+        expect(vm.$el).toContainText('Only comments from the following commit are shown below');
+      })
+      .then(done)
+      .catch(done.fail);
+  });
+
+  it('shows comments message, with old mergeRequestDiff', done => {
+    vm.$store.state.diffs.mergeRequestDiff = {
+      latest: false,
+    };
+
+    vm.$nextTick()
+      .then(() => {
+        expect(vm.$el).toContainText("Not all comments are displayed because you're viewing an old version of the diff.");
+      })
+      .then(done)
+      .catch(done.fail);
+  });
+
+  it('shows comments message, with startVersion', done => {
+    vm.$store.state.diffs.startVersion = 'test';
+
+    vm.$nextTick()
+      .then(() => {
+        expect(vm.$el).toContainText("Not all comments are displayed because you're comparing two versions of the diff.");
+      })
+      .then(done)
+      .catch(done.fail);
+  });
+});
diff --git a/spec/javascripts/diffs/create_mock_store.js b/spec/javascripts/diffs/create_mock_store.js
new file mode 100644
index 00000000000..5333ea38931
--- /dev/null
+++ b/spec/javascripts/diffs/create_mock_store.js
@@ -0,0 +1,16 @@
+import Vue from 'vue';
+import Vuex from 'vuex';
+import diffsModule from '~/diffs/store/modules';
+import notesModule from '~/notes/stores/modules';
+import mockVuexModule from 'spec/helpers/mock_vuex_module';
+
+Vue.use(Vuex);
+
+export default function createDiffsStore() {
+  return new Vuex.Store(mockVuexModule({
+    modules: {
+      diffs: diffsModule,
+      notes: notesModule,
+    },
+  }));
+}