fix(vitest): support assets in new URL in Vite 5 (#4258)

Author: sheremet-va

Diff for: .eslintrc

@@ -14,7 +14,8 @@
         "paths": ["path"]
       }
     ],
-    "import/no-named-as-default": "off"
+    "import/no-named-as-default": "off",
+    "no-cond-assign": "off"
   },
   "overrides": [
     {

Diff for: packages/vitest/src/node/plugins/index.ts

@@ -14,6 +14,7 @@ import { MocksPlugin } from './mocks'
 import { deleteDefineConfig, hijackVitePluginInject, resolveFsAllow } from './utils'
 import { VitestResolver } from './vitestResolver'
 import { VitestOptimizer } from './optimizer'
+import { NormalizeURLPlugin } from './normalizeURL'
 
 export async function VitestPlugin(options: UserConfig = {}, ctx = new Vitest('test')): Promise<VitePlugin[]> {
   const userConfig = deepMerge({}, options) as UserConfig
@@ -185,6 +186,7 @@ export async function VitestPlugin(options: UserConfig = {}, ctx = new Vitest('t
     MocksPlugin(),
     VitestResolver(ctx),
     VitestOptimizer(),
+    NormalizeURLPlugin(),
   ]
     .filter(notNullish)
 }

Diff for: packages/vitest/src/node/plugins/normalizeURL.ts

@@ -0,0 +1,38 @@
+import { stripLiteral } from 'strip-literal'
+import type { Plugin } from 'vite'
+
+const metaUrlLength = 'import.meta.url'.length
+const locationString = 'self.location'.padEnd(metaUrlLength, ' ')
+
+// Vite transforms new URL('./path', import.meta.url) to new URL('/path.js', import.meta.url)
+// This makes "href" equal to "http://localhost:3000/path.js" in the browser, but if we keep it like this,
+// then in tests the URL will become "file:///path.js".
+// To battle this, we replace "import.meta.url" with "self.location" in the code to keep the browser behavior.
+export function NormalizeURLPlugin(): Plugin {
+  return {
+    name: 'vitest:normalize-url',
+    enforce: 'post',
+    transform(code, id, options) {
+      const ssr = options?.ssr === true
+      if (ssr || !code.includes('new URL') || !code.includes('import.meta.url'))
+        return
+
+      const cleanString = stripLiteral(code)
+      const assetImportMetaUrlRE
+      = /\bnew\s+URL\s*\(\s*('[^']+'|"[^"]+"|`[^`]+`)\s*,\s*import\.meta\.url\s*(?:,\s*)?\)/g
+
+      let updatedCode = code
+      let match: RegExpExecArray | null
+      while ((match = assetImportMetaUrlRE.exec(cleanString))) {
+        const { 0: exp, index } = match
+        const metaUrlIndex = index + exp.indexOf('import.meta.url')
+        updatedCode = updatedCode.slice(0, metaUrlIndex) + locationString + updatedCode.slice(metaUrlIndex + metaUrlLength)
+      }
+
+      return {
+        code: updatedCode,
+        map: null,
+      }
+    },
+  }
+}

Diff for: packages/vitest/src/node/plugins/ssrReplacer.ts

@@ -10,7 +10,7 @@ export function SsrReplacerPlugin(): Plugin {
     name: 'vitest:ssr-replacer',
     enforce: 'pre',
     transform(code, id) {
-      if (!/\bimport\.meta\.env\b/.test(code) && !/\bimport\.meta\.url\b/.test(code))
+      if (!/\bimport\.meta\.env\b/.test(code))
         return null
 
       let s: MagicString | null = null

Diff for: packages/vitest/src/node/plugins/workspace.ts

@@ -12,6 +12,7 @@ import { MocksPlugin } from './mocks'
 import { deleteDefineConfig, hijackVitePluginInject, resolveFsAllow } from './utils'
 import { VitestResolver } from './vitestResolver'
 import { VitestOptimizer } from './optimizer'
+import { NormalizeURLPlugin } from './normalizeURL'
 
 interface WorkspaceOptions extends UserWorkspaceConfig {
   root?: string
@@ -125,5 +126,6 @@ export function WorkspaceVitestPlugin(project: WorkspaceProject, options: Worksp
     MocksPlugin(),
     VitestResolver(project.ctx),
     VitestOptimizer(),
+    NormalizeURLPlugin(),
   ]
 }