Fix App callCount test by no longer stubbing free-standing function getCurrentUser due to version change

It turns out that you can no longer stub free-standing functions in Typescript 3.9.2+ according to this issue:

microsoft/TypeScript#38568
sinonjs/sinon#562

The test in App.test.tsx was failing when it tried to get the callCount for a stub for a free-standing function getCurrentUser, and currently, my package-lock.json has 3.9.5, so that appears to be why. My fix was to use an object where the functions become methods instead.

Author: natalynyu

src/client/components/App.tsx

@@ -32,7 +32,7 @@ import {
   PageTitle,
   Link,
 } from 'mark-one';
-import { getCurrentUser } from 'client/api';
+import { UserAPI } from 'client/api';
 import { UserResponse } from 'common/dto/users/userResponse.dto';
 import { MetadataContext } from 'client/context/MetadataContext';
 import { getMetadata } from 'client/api/metadata';
@@ -76,7 +76,7 @@ const ColdApp: SFC = (): ReactElement => {
    */
 
   useEffect((): void => {
-    getCurrentUser()
+    UserAPI.getCurrentUser()
       .then(({ data: user }): UserResponse => {
         setUser(user);
         return user;

src/client/components/__tests__/App.test.tsx

@@ -10,14 +10,14 @@ import { stub, SinonStub } from 'sinon';
 import { AxiosResponse } from 'axios';
 import { UserResponse } from 'common/dto/users/userResponse.dto';
 import * as dummy from 'testData';
-import * as api from 'client/api';
+import { UserAPI } from 'client/api';
 import { MarkOneTheme } from 'mark-one';
 import { App } from '../App';
 
 describe('App', function () {
   let apiStub: SinonStub;
   beforeEach(function () {
-    apiStub = stub(api, 'getCurrentUser');
+    apiStub = stub(UserAPI, 'getCurrentUser');
     apiStub.resolves({
       data: dummy.regularUser,
     } as AxiosResponse<UserResponse>);
@@ -154,9 +154,10 @@ describe('App', function () {
             <App />
           </MemoryRouter>
         );
-        strictEqual(apiStub.callCount, 1);
         const { fullName } = dummy.regularUser;
-        return waitForElement(() => getByText(fullName, { exact: false }));
+        await waitForElement(() => getByText(fullName, { exact: false }));
+        strictEqual(apiStub.callCount, 1);
+        return getByText(fullName, { exact: false });
       });
     });
     context('When userFetch fails', function () {