Add mocked test users

src/api.test.ts

@@ -0,0 +1,24 @@
+import { applyMiddleware, legacy_createStore as createStore } from 'redux';
+import { thunk } from 'redux-thunk';
+
+import { requestLogin, requestUserData } from '@/api';
+import rootReducer from '@/reducers';
+
+const createTestStore = () => createStore(rootReducer, undefined, applyMiddleware(thunk));
+
+describe('dev fake users (__DEV__ only)', () => {
+  it.each([
+    ['nonmember', false],
+    ['member', true],
+  ])('logs in "%s" with a fake user without hitting the network', async (username, isMember) => {
+    const store = createTestStore();
+
+    await store.dispatch(requestLogin(username as string, 'any-password'));
+    expect(store.getState().isAuthenticated).toBe(true);
+
+    await store.dispatch(requestUserData(store.getState().userToken ?? ''));
+    expect(store.getState().user?.is_member).toBe(isMember);
+
+    expect(global.fetch).not.toHaveBeenCalled();
+  });
+});