replace process.env.NODE_ENV at build time and enable react module-resolution build test

packages/vite-plugin-cloudflare/package.json

@@ -36,6 +36,7 @@
 	},
 	"dependencies": {
 		"@hattip/adapter-node": "^0.0.49",
+		"@rollup/plugin-replace": "^6.0.1",
 		"miniflare": "^3.20241205.0"
 	},
 	"devDependencies": {

packages/vite-plugin-cloudflare/src/cloudflare-environment.ts

@@ -1,5 +1,6 @@
 import assert from 'node:assert';
 import { builtinModules } from 'node:module';
+import replace from '@rollup/plugin-replace';
 import * as vite from 'vite';
 import { getNodeCompatExternals } from './node-js-compat';
 import { INIT_PATH, UNKNOWN_HOST } from './shared';
@@ -153,6 +154,13 @@ export function createCloudflareEnvironmentOptions(
 				//       optimizeDeps.entries in the dev config)
 				input: workerConfig.main,
 				external: [...cloudflareBuiltInModules, ...getNodeCompatExternals()],
+				plugins: [
+					replace({
+						'process.env.NODE_ENV': JSON.stringify(
+							process.env.NODE_ENV ?? 'production',
+						),
+					}),
+				],
 			},
 		},
 		optimizeDeps: {

playground/module-resolution/__tests__/module-resolution.spec.ts

@@ -76,9 +76,7 @@ describe('module resolution', async () => {
 	 *  special meaning to us.
 	 */
 	describe('third party packages resolutions', () => {
-		// TODO: we skip this test on build because a `ReferenceError: process is not defined` is thrown
-		//       (https://github.com/flarelabs-net/vite-plugin-cloudflare/issues/82)
-		test.skipIf(isBuild)('react', async () => {
+		test('react', async () => {
 			const result = await getJsonResponse('/third-party/react');
 			expect(result).toEqual({
 				'(react) reactVersionsMatch': true,