Vite 8 upgrade: use rolldownOptions and oxc in config

Author: marlo-longley

vite.config.js

@@ -13,7 +13,7 @@ export default defineConfig({
   ...(
     process.env.NETLIFY ? {
       build: {
-        rollupOptions: {
+        rolldownOptions: {
           external: ['__tests__/*', '__mocks__/*'],
           input: Object.fromEntries(
             globSync('./demo/*.html').map((file) => [
@@ -39,7 +39,7 @@ export default defineConfig({
           formats: ['es'],
           name: 'Mirador',
         },
-        rollupOptions: {
+        rolldownOptions: {
           external: (id, parentId) => {
             const peers = Object.keys(packageJson.peerDependencies);
             return peers.indexOf(id) > -1

vitest.config.ts

@@ -1,30 +1,11 @@
 /// <reference types="vitest" />
-import { defineConfig } from 'vite';
+import { defineConfig } from 'vitest/config';
 import react from '@vitejs/plugin-react';
 import { fileURLToPath } from 'url';
-import fs from 'fs/promises';
-
 export default defineConfig({
-  esbuild: {
+  oxc: {
     exclude: [],
     include: /(src|__tests__)\/.*\.jsx?$/,
-    loader: 'jsx',
-  },
-  optimizeDeps: {
-    esbuildOptions: {
-      plugins: [
-        {
-          name: 'load-js-files-as-jsx',
-          /** */
-          setup(build) {
-            build.onLoad({ filter: /(src|__tests__)\/.*\.js$/ }, async (args) => ({
-              contents: await fs.readFile(args.path, 'utf8'),
-              loader: 'jsx',
-            }));
-          },
-        },
-      ],
-    },
   },
   plugins: [react()],
   resolve: {