fix(vitest): always resolve vitest to the root version (#6369)

packages/vitest/src/node/plugins/index.ts

@@ -21,7 +21,6 @@ import {
   hijackVitePluginInject,
   resolveFsAllow,
 } from './utils'
-import { VitestResolver } from './vitestResolver'
 import { VitestOptimizer } from './optimizer'
 import { NormalizeURLPlugin } from './normalizeURL'
 
@@ -256,7 +255,6 @@ export async function VitestPlugin(
     CoverageTransform(ctx),
     options.ui ? await UIPlugin() : null,
     ...MocksPlugins(),
-    VitestResolver(ctx),
     VitestOptimizer(),
     NormalizeURLPlugin(),
   ].filter(notNullish)

packages/vitest/src/node/plugins/vitestResolver.ts

@@ -1,17 +1,21 @@
 import type { Plugin } from 'vite'
-import { join } from 'pathe'
 import type { Vitest } from '../core'
 
 export function VitestResolver(ctx: Vitest): Plugin {
-  return {
+  const plugin: Plugin = {
     name: 'vitest:resolve-root',
     enforce: 'pre',
-    async resolveId(id) {
+    async resolveId(id, _, { ssr }) {
       if (id === 'vitest' || id.startsWith('@vitest/')) {
-        return this.resolve(id, join(ctx.config.root, 'index.html'), {
-          skipSelf: true,
+        // always redirect the request to the root vitest plugin since
+        // it will be the one used to run Vitest
+        const resolved = await ctx.server.pluginContainer.resolveId(id, undefined, {
+          skip: new Set([plugin]),
+          ssr,
         })
+        return resolved
       }
     },
   }
+  return plugin
 }

test/workspaces/space_3/fake-vitest/config.js

@@ -0,0 +1,3 @@
+exports.defineProject = (c) => {
+  return c
+}

test/workspaces/space_3/fake-vitest/index.js

@@ -0,0 +1 @@
+throw new Error('should not import from fake vitest')

test/workspaces/space_3/fake-vitest/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "vitest",
+  "type": "commonjs",
+  "exports": {
+    ".": "./index.js",
+    "./config": "./config.js"
+  }
+}

test/workspaces/space_3/package.json

@@ -1,4 +1,10 @@
 {
   "name": "@vitest/space_3",
-  "private": true
+  "private": true,
+  "scripts": {
+    "test": "vitest"
+  },
+  "dependencies": {
+    "vitest": "link:./fake-vitest"
+  }
 }