chore(e2e): add warning message for e2e in nuxt vitest setup

Author: yamachi4416

src/config.ts

@@ -137,6 +137,7 @@ export async function getVitestConfigFromNuxt(
     {
       define: {
         'process.env.NODE_ENV': '"test"',
+        'process.env.__NUXT_VITEST_RESOLVED__': '"true"',
       },
       resolve: {
         alias: {

src/e2e/setup/index.ts

@@ -75,6 +75,12 @@ export function createTest(options: Partial<TestOptions>): TestHooks {
 }
 
 export async function setup(options: Partial<TestOptions> = {}) {
+  if (process.env.__NUXT_VITEST_RESOLVED__) {
+    console.warn(
+      'Do not use defineVitestConfig or defineVitestProject for end-to-end tests, as they only work with nuxt client-environment tests.\n'
+      + 'Please refer to the setup section: https://nuxt.com/docs/4.x/getting-started/testing#setup')
+  }
+
   const hooks = createTest(options)
 
   const setupFn = setupMaps[hooks.ctx.options.runner]