fix(vitest): dispose vmForks listeners to avoid memory leak (#6448)

packages/vitest/src/runtime/worker.ts

@@ -7,13 +7,16 @@ import type { ContextRPC, WorkerGlobalState } from '../types/worker'
 import { setupInspect } from './inspector'
 import { createRuntimeRpc, rpcDone } from './rpc'
 import type { VitestWorker } from './workers/types'
+import { disposeInternalListeners } from './workers/utils'
 
 if (isChildProcess()) {
   setProcessTitle(`vitest ${poolId}`)
 }
 
 // this is what every pool executes when running tests
 async function execute(mehtod: 'run' | 'collect', ctx: ContextRPC) {
+  disposeInternalListeners()
+
   const prepareStart = performance.now()
 
   const inspectorCleanup = setupInspect(ctx)

packages/vitest/src/runtime/workers/utils.ts

@@ -9,6 +9,8 @@ const REGEXP_WRAP_PREFIX = '$$vitest:'
 // Store global APIs in case process is overwritten by tests
 const processSend = process.send?.bind(process)
 const processOn = process.on?.bind(process)
+const processOff = process.off?.bind(process)
+const dispose: (() => void)[] = []
 
 export function createThreadsRpcOptions({
   port,
@@ -23,6 +25,16 @@ export function createThreadsRpcOptions({
   }
 }
 
+export function disposeInternalListeners() {
+  for (const fn of dispose) {
+    try {
+      fn()
+    }
+    catch {}
+  }
+  dispose.length = 0
+}
+
 export function createForksRpcOptions(
   nodeV8: typeof import('v8'),
 ): WorkerRpcOptions {
@@ -33,14 +45,16 @@ export function createForksRpcOptions(
       processSend!(v)
     },
     on(fn) {
-      processOn('message', (message: any, ...extras: any) => {
+      const handler = (message: any, ...extras: any) => {
         // Do not react on Tinypool's internal messaging
         if ((message as TinypoolWorkerMessage)?.__tinypool_worker_message__) {
           return
         }
 
         return fn(message, ...extras)
-      })
+      }
+      processOn('message', handler)
+      dispose.push(() => processOff('message', handler))
     },
   }
 }