Migrate from rollup to rolldown (#3578)

* Migrate from rollup to rolldown

* use defineConfig

* tweak command

* update rolldown

* update rolldown

* update rolldown config

* don't need this

* add todo, remove other comment

* remove most babel deps

* update rolldown

* use output array

* pin @vitest/eslint-plugin

Author: nstepien

babel.config.json

@@ -1,18 +1,3 @@
 {
-  "presets": [
-    [
-      "@babel/env",
-      {
-        "loose": true,
-        "bugfixes": true,
-        "shippedProposals": true
-      }
-    ],
-    ["@babel/react", { "runtime": "automatic" }],
-    "@babel/typescript"
-  ],
-  "plugins": [
-    "@babel/transform-runtime",
-    ["optimize-clsx", { "functionNames": ["getCellClassname"] }]
-  ]
+  "presets": ["@babel/typescript"]
 }

package.json

@@ -36,7 +36,7 @@
     "start": "vite serve --clearScreen false",
     "preview": "vite preview",
     "build:website": "vite build",
-    "build": "rollup --config --no-stdin",
+    "build": "rolldown -c",
     "build:types": "tsc -p tsconfig.lib.json && api-extractor run --local --verbose",
     "test": "vitest run",
     "test:watch": "vitest watch",
@@ -55,21 +55,14 @@
     "clsx": "^2.0.0"
   },
   "devDependencies": {
-    "@babel/core": "^7.26.0",
-    "@babel/plugin-transform-runtime": "^7.25.9",
-    "@babel/preset-env": "^7.26.0",
-    "@babel/preset-react": "^7.26.3",
     "@babel/preset-typescript": "^7.26.0",
-    "@babel/runtime": "^7.26.0",
     "@biomejs/biome": "1.9.4",
     "@eslint/compat": "^1.2.4",
     "@eslint/markdown": "^6.2.1",
     "@faker-js/faker": "^9.3.0",
     "@ianvs/prettier-plugin-sort-imports": "^4.0.2",
     "@linaria/core": "^6.0.0",
     "@microsoft/api-extractor": "^7.48.1",
-    "@rollup/plugin-babel": "^6.0.4",
-    "@rollup/plugin-node-resolve": "^16.0.0",
     "@tanstack/react-router": "^1.85.5",
     "@tanstack/router-plugin": "^1.69.1",
     "@testing-library/dom": "^10.1.0",
@@ -83,10 +76,9 @@
     "@vitejs/plugin-react": "^4.3.4",
     "@vitest/browser": "^2.1.8",
     "@vitest/coverage-v8": "^2.1.8",
-    "@vitest/eslint-plugin": "^1.1.17",
+    "@vitest/eslint-plugin": "1.1.20",
     "@wyw-in-js/rollup": "^0.5.0",
     "@wyw-in-js/vite": "^0.5.0",
-    "babel-plugin-optimize-clsx": "^2.6.2",
     "browserslist": "^4.24.3",
     "eslint": "^9.17.0",
     "eslint-plugin-jest-dom": "^5.5.0",
@@ -105,8 +97,7 @@
     "react-dnd": "^16.0.1",
     "react-dnd-html5-backend": "^16.0.1",
     "react-dom": "^18.3.1",
-    "rollup": "^4.28.1",
-    "rollup-plugin-postcss": "^4.0.2",
+    "rolldown": "^1.0.0-beta.1",
     "typescript": "~5.7.2",
     "vite": "^6.0.3",
     "vitest": "^2.1.8",

rolldown.config.js

@@ -0,0 +1,41 @@
+// @ts-check
+import { isAbsolute } from 'node:path';
+import wyw from '@wyw-in-js/rollup';
+import pkg from './package.json' with { type: 'json' };
+import { defineConfig } from 'rolldown';
+
+export default defineConfig({
+  input: './src/index.ts',
+  output: [
+    {
+      dir: 'lib',
+      entryFileNames: 'bundle.js',
+      cssEntryFileNames: 'styles.css',
+      format: 'es',
+      sourcemap: true
+    },
+    {
+      dir: 'lib',
+      entryFileNames: 'bundle.cjs',
+      cssEntryFileNames: 'styles.css',
+      format: 'cjs',
+      sourcemap: true
+    }
+  ],
+  platform: 'browser',
+  external: (id) => !id.startsWith('.') && !isAbsolute(id),
+  plugins: [
+    // @ts-expect-error
+    wyw({
+      preprocessor: 'none',
+      /**
+       * @param {string} hash
+       */
+      classNameSlug(hash) {
+        // We add the package version as suffix to avoid style conflicts
+        // between multiple versions of RDG on the same page.
+        return `${hash}${pkg.version.replaceAll('.', '-')}`;
+      }
+    })
+  ]
+});

rollup.config.js

@@ -4,8 +4,9 @@
     "allowJs": true,
     "module": "NodeNext",
     "moduleResolution": "NodeNext",
+    "resolveJsonModule": true,
     "skipLibCheck": true
   },
-  "include": ["**/*.js", ".github/**/*.js"],
+  "include": ["**/*.js", ".github/**/*.js", "package.json"],
   "exclude": ["./coverage/**/*", "./dist/**/*", "./lib/**/*"]
 }