Wire up role dropdown with Vuex action

Part of a larger initiative to convert the group members view from
HAML to Vue

app/assets/javascripts/groups/members/index.js

 import Vue from 'vue';
 import Vuex from 'vuex';
+import { GlToast } from '@gitlab/ui';
 import { parseDataAttributes } from 'ee_else_ce/groups/members/utils';
 import App from './components/app.vue';
 import membersModule from '~/vuex_shared/modules/members';
@@ -10,6 +11,7 @@ export const initGroupMembersApp = (el, tableFields, requestFormatter) => {
   }
 
   Vue.use(Vuex);
+  Vue.use(GlToast);
 
   const store = new Vuex.Store({
     ...membersModule({

app/assets/javascripts/vue_shared/components/members/table/role_dropdown.vue

 <script>
 import { GlDropdown, GlDropdownItem } from '@gitlab/ui';
 import { GlBreakpointInstance as bp } from '@gitlab/ui/dist/utils';
+import { mapActions } from 'vuex';
+import { s__ } from '~/locale';
 
 export default {
   name: 'RoleDropdown',
@@ -17,14 +19,32 @@ export default {
   data() {
     return {
       isDesktop: false,
+      busy: false,
     };
   },
   mounted() {
     this.isDesktop = bp.isDesktop();
   },
   methods: {
-    handleSelect() {
-      // Vuex action will be called here to make API request and update `member.accessLevel`
+    ...mapActions(['updateMemberRole']),
+    handleSelect(value, name) {
+      if (value === this.member.accessLevel.integerValue) {
+        return;
+      }
+
+      this.busy = true;
+
+      this.updateMemberRole({
+        memberId: this.member.id,
+        accessLevel: { integerValue: value, stringValue: name },
+      })
+        .then(() => {
+          this.$toast.show(s__('Members|Role updated successfully.'));
+          this.busy = false;
+        })
+        .catch(() => {
+          this.busy = false;
+        });
     },
   },
 };
@@ -35,13 +55,14 @@ export default {
     :right="!isDesktop"
     :text="member.accessLevel.stringValue"
     :header-text="__('Change permissions')"
+    :disabled="busy"
   >
     <gl-dropdown-item
       v-for="(value, name) in member.validRoles"
       :key="value"
       is-check-item
       :is-checked="value === member.accessLevel.integerValue"
-      @click="handleSelect"
+      @click="handleSelect(value, name)"
     >
       {{ name }}
     </gl-dropdown-item>

locale/gitlab.pot

@@ -16193,6 +16193,9 @@ msgstr ""
 msgid "Members|No expiration set"
 msgstr ""
 
+msgid "Members|Role updated successfully."
+msgstr ""
+
 msgid "Members|in %{time}"
 msgstr ""
 

spec/frontend/vue_shared/components/members/table/role_dropdown_spec.js

-import { mount, createWrapper } from '@vue/test-utils';
+import { mount, createWrapper, createLocalVue } from '@vue/test-utils';
+import Vuex from 'vuex';
 import { nextTick } from 'vue';
 import { within } from '@testing-library/dom';
 import { GlDropdown, GlDropdownItem } from '@gitlab/ui';
 import { GlBreakpointInstance as bp } from '@gitlab/ui/dist/utils';
+import waitForPromises from 'helpers/wait_for_promises';
 import RoleDropdown from '~/vue_shared/components/members/table/role_dropdown.vue';
 import { member } from '../mock_data';
 
+const localVue = createLocalVue();
+localVue.use(Vuex);
+
 describe('RoleDropdown', () => {
   let wrapper;
+  let actions;
+  const $toast = {
+    show: jest.fn(),
+  };
+
+  const createStore = () => {
+    actions = {
+      updateMemberRole: jest.fn(() => Promise.resolve()),
+    };
+
+    return new Vuex.Store({ actions });
+  };
 
   const createComponent = (propsData = {}) => {
     wrapper = mount(RoleDropdown, {
@@ -15,6 +32,11 @@ describe('RoleDropdown', () => {
         member,
         ...propsData,
       },
+      localVue,
+      store: createStore(),
+      mocks: {
+        $toast,
+      },
     });
   };
 
@@ -22,7 +44,11 @@ describe('RoleDropdown', () => {
   const getByTextInDropdownMenu = (text, options = {}) =>
     createWrapper(within(getDropdownMenu()).getByText(text, options));
   const getDropdownItemByText = text =>
-    getByTextInDropdownMenu(text, { selector: '[role="menuitem"] p' });
+    createWrapper(
+      within(getDropdownMenu())
+        .getByText(text, { selector: '[role="menuitem"] p' })
+        .closest('[role="menuitem"]'),
+    );
   const getCheckedDropdownItem = () =>
     wrapper
       .findAll(GlDropdownItem)
@@ -55,10 +81,47 @@ describe('RoleDropdown', () => {
       expect(getByTextInDropdownMenu('Change permissions').exists()).toBe(true);
     });
 
-    it('sets dropdown toggle and checks selected role', async () => {
+    it('sets dropdown toggle and checks selected role', () => {
       expect(findDropdownToggle().text()).toBe('Owner');
       expect(getCheckedDropdownItem().text()).toBe('Owner');
     });
+
+    describe('when dropdown item is selected', () => {
+      it('does nothing if the item selected was already selected', () => {
+        getDropdownItemByText('Owner').trigger('click');
+
+        expect(actions.updateMemberRole).not.toHaveBeenCalled();
+      });
+
+      it('calls `updateMemberRole` Vuex action', () => {
+        getDropdownItemByText('Developer').trigger('click');
+
+        expect(actions.updateMemberRole).toHaveBeenCalledWith(expect.any(Object), {
+          memberId: member.id,
+          accessLevel: { integerValue: 30, stringValue: 'Developer' },
+        });
+      });
+
+      it('displays toast when successful', async () => {
+        getDropdownItemByText('Developer').trigger('click');
+
+        await waitForPromises();
+
+        expect($toast.show).toHaveBeenCalledWith('Role updated successfully.');
+      });
+
+      it('disables dropdown while waiting for `updateMemberRole` to resolve', async () => {
+        getDropdownItemByText('Developer').trigger('click');
+
+        await nextTick();
+
+        expect(findDropdown().attributes('disabled')).toBe('disabled');
+
+        await waitForPromises();
+
+        expect(findDropdown().attributes('disabled')).toBeUndefined();
+      });
+    });
   });
 
   it("sets initial dropdown toggle value to member's role", () => {