refactor: define dependencies correctly

packages/browser/package.json

@@ -87,6 +87,7 @@
     "periscopic": "^4.0.2",
     "playwright": "^1.44.0",
     "playwright-core": "^1.44.0",
+    "rollup-plugin-copy": "^3.5.0",
     "safaridriver": "^0.1.2",
     "vitest": "workspace:*",
     "webdriverio": "^8.36.1"
@@ -96,4 +97,4 @@
       "msw"
     ]
   }
-}
+}

packages/browser/src/client/mocker.ts

@@ -1,5 +1,6 @@
 import { getType } from '@vitest/utils'
 import { extname, join } from 'pathe'
+import type { SetupWorker } from 'msw/browser'
 import { setupWorker } from 'msw/browser'
 import { HttpResponse, http, passthrough } from 'msw'
 import { rpc } from './rpc'
@@ -24,9 +25,13 @@ export class VitestBrowserClientMocker {
   private factories: Record<string, () => any> = {}
 
   private spyModule!: SpyModule
+  private mswWorker!: SetupWorker
 
-  startWorker() {
-    const worker = setupWorker(
+  private _mswStarted = false
+  private _mswPromise: Promise<unknown> | null = null
+
+  setupWorker() {
+    this.mswWorker = setupWorker(
       http.get(/.+/, async ({ request }) => {
         const path = cleanTimestamp(request.url.slice(location.origin.length))
         if (!(path in this.mocks))
@@ -63,12 +68,23 @@ export class VitestBrowserClientMocker {
         })
       }),
     )
-    return worker.start({
+  }
+
+  public async startMSW() {
+    if (this._mswStarted)
+      return
+    if (this._mswPromise)
+      return this._mswPromise
+    this._mswPromise = this.mswWorker.start({
       serviceWorker: {
         url: '/__virtual_vitest__:mocker-worker.js',
       },
       quiet: true,
+    }).then(() => {
+      this._mswStarted = true
+      this._mswPromise = null
     })
+    await this._mswPromise
   }
 
   public setSpyModule(mod: SpyModule) {
@@ -168,7 +184,10 @@ export class VitestBrowserClientMocker {
   public async prepare() {
     if (!this.queue.size)
       return
-    await Promise.all([...this.queue.values()])
+    await Promise.all([
+      this.startMSW(),
+      ...this.queue.values(),
+    ])
   }
 
   // TODO: move this logic into a util(?)

packages/browser/src/client/tester.ts

@@ -133,7 +133,7 @@ async function prepareTestEnvironment(files: string[]) {
   registerUnexpectedErrors(rpc)
 
   try {
-    await mocker.startWorker()
+    await mocker.setupWorker()
   }
   catch (err) {
     console.error(err)

packages/vitest/package.json

@@ -147,12 +147,14 @@
     }
   },
   "dependencies": {
+    "@ampproject/remapping": "^2.3.0",
     "@vitest/expect": "workspace:*",
     "@vitest/runner": "workspace:*",
     "@vitest/snapshot": "workspace:*",
     "@vitest/spy": "workspace:*",
     "@vitest/utils": "workspace:*",
     "chai": "^5.1.1",
+    "debug": "^4.3.4",
     "execa": "^8.0.1",
     "magic-string": "^0.30.10",
     "pathe": "^1.1.2",
@@ -165,7 +167,6 @@
     "why-is-node-running": "^2.2.2"
   },
   "devDependencies": {
-    "@ampproject/remapping": "^2.3.0",
     "@antfu/install-pkg": "0.3.1",
     "@edge-runtime/vm": "^3.2.0",
     "@sinonjs/fake-timers": "11.1.0",
@@ -183,7 +184,6 @@
     "cac": "^6.7.14",
     "chai-subset": "^1.6.0",
     "cli-truncate": "^4.0.0",
-    "debug": "^4.3.4",
     "expect-type": "^0.19.0",
     "fast-glob": "^3.3.2",
     "find-up": "^6.3.0",