fix: config.root priority (#1164)

* fix: config.root priority

* test: add vite config root test

packages/vitest/src/node/create.ts

@@ -16,15 +16,14 @@ export async function createVitest(options: UserConfig, viteOverrides: ViteUserC
     : await findUp(configFiles, { cwd: root } as any)
 
   const config: ViteInlineConfig = {
-    root,
     logLevel: 'error',
     configFile: configPath,
     // this will make "mode" = "test" inside defineConfig
     mode: options.mode || process.env.NODE_ENV || 'test',
     plugins: await VitestPlugin(options, ctx),
   }
 
-  const server = await createServer(mergeConfig(config, viteOverrides))
+  const server = await createServer(mergeConfig(config, mergeConfig(viteOverrides, { root: options.root })))
 
   if (ctx.config.api?.port)
     await server.listen()

test/vite-config/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "@vitest/test-vite-config",
+  "private": true,
+  "scripts": {
+    "test": "vitest",
+    "coverage": "vitest run --coverage"
+  },
+  "devDependencies": {
+    "pathe": "^0.2.0",
+    "vitest": "workspace:*"
+  }
+}

test/vite-config/src/index.html

@@ -0,0 +1 @@
+Hello Vitest

test/vite-config/src/test/root.test.ts

@@ -0,0 +1,5 @@
+import { it } from 'vitest'
+
+it('should work', () => {
+  //
+})

test/vite-config/vite.config.ts

@@ -0,0 +1,19 @@
+/// <reference types="vitest" />
+
+import assert from 'assert'
+import { join } from 'pathe'
+import { defineConfig } from 'vite'
+
+const configRoot = join(__dirname, 'src')
+
+export default defineConfig({
+  root: configRoot,
+  plugins: [
+    {
+      name: 'root-checker',
+      configResolved(config) {
+        assert.equal(config.root, configRoot)
+      },
+    },
+  ],
+})