test: data router, one render helper, fetchRoutes in every test

src/components/GameMergeDialog.test.jsx

@@ -4,6 +4,7 @@ import {cleanup, fireEvent, render, screen, waitFor} from '@testing-library/reac
 import {MemoryRouter} from 'react-router-dom';
 import {toast} from 'sonner';
 import GameMergeDialog from './GameMergeDialog.jsx';
+import {fetchRoutes, json} from '../test/fetchRoutes.js';
 
 vi.mock('react-i18next', () => import('../test/i18n-mock.js'));
 vi.mock('sonner', () => ({toast: {success: vi.fn(), error: vi.fn()}}));
@@ -12,12 +13,11 @@ const hades = {appid: 1145360, name: 'Hades'};
 const hit = (appid, name) => ({appid, igdbId: Math.abs(appid), name, year: 2020, imageUrl: null,
     platforms: ['Switch'], inLibrary: false, inCatalog: true});
 
-const json = (status, body) => ({ok: status < 400, status, json: async () => body});
-
 function renderDialog(game, post, results) {
-    globalThis.fetch = vi.fn(async (url, init) => init?.method === 'POST'
-        ? post
-        : json(200, {available: true, results}));
+    fetchRoutes({
+        'GET /api/library/game-search': json(200, {available: true, results}),
+        [`POST /api/library/games/${game.appid}/merge`]: post,
+    });
     const onMerged = vi.fn();
     render(<MemoryRouter><GameMergeDialog game={game} open onOpenChange={vi.fn()} onMerged={onMerged}/></MemoryRouter>);
     return onMerged;