fix(launcher): unregister global process handlers when all browser are closed (#29011)

Otherwise, we forever block SIGTERM and SIGHUP by registering a handler
that does not do anything (due to no browsers to close) and prevents
default handler that exits from running.

Fixes #28091.

packages/playwright-core/src/utils/processLauncher.ts

@@ -121,6 +121,13 @@ function addProcessHandlerIfNeeded(name: 'exit' | 'SIGINT' | 'SIGTERM' | 'SIGHUP
     process.on(name, processHandlers[name]);
   }
 }
+function removeProcessHandlersIfNeeded() {
+  if (killSet.size)
+    return;
+  for (const handler of installedHandlers)
+    process.off(handler, processHandlers[handler]);
+  installedHandlers.clear();
+}
 
 export async function launchProcess(options: LaunchProcessOptions): Promise<LaunchResult> {
   const stdio: ('ignore' | 'pipe')[] = options.stdio === 'pipe' ? ['ignore', 'pipe', 'pipe', 'pipe', 'pipe'] : ['pipe', 'pipe', 'pipe'];
@@ -178,6 +185,7 @@ export async function launchProcess(options: LaunchProcessOptions): Promise<Laun
     processClosed = true;
     gracefullyCloseSet.delete(gracefullyClose);
     killSet.delete(killProcessAndCleanup);
+    removeProcessHandlersIfNeeded();
     options.onExit(exitCode, signal);
     // Cleanup as process exits.
     cleanup().then(fulfillCleanup);
@@ -216,6 +224,7 @@ export async function launchProcess(options: LaunchProcessOptions): Promise<Laun
   function killProcess() {
     gracefullyCloseSet.delete(gracefullyClose);
     killSet.delete(killProcessAndCleanup);
+    removeProcessHandlersIfNeeded();
     options.log(`[pid=${spawnedProcess.pid}] <kill>`);
     if (spawnedProcess.pid && !spawnedProcess.killed && !processClosed) {
       options.log(`[pid=${spawnedProcess.pid}] <will force kill>`);

tests/config/remote-server-impl.js

@@ -2,7 +2,7 @@ const fs = require('fs');
 const cluster = require('cluster');
 
 async function start() {
-  const { browserTypeName, launchOptions, stallOnClose, disconnectOnSIGHUP, exitOnFile, exitOnWarning } = JSON.parse(process.argv[2]);
+  const { browserTypeName, launchOptions, stallOnClose, disconnectOnSIGHUP, exitOnFile, exitOnWarning, startStopAndRunHttp } = JSON.parse(process.argv[2]);
   if (stallOnClose) {
     launchOptions.__testHookGracefullyClose = () => {
       console.log(`(stalled=>true)`);
@@ -11,11 +11,20 @@ async function start() {
   }
   if (exitOnWarning)
     process.on('warning', () => process.exit(43));
+  if (disconnectOnSIGHUP)
+    launchOptions.handleSIGHUP = false;
 
   const playwright = require('playwright-core');
 
-  if (disconnectOnSIGHUP)
+  if (startStopAndRunHttp) {
-    launchOptions.handleSIGHUP = false;
+    const browser = await playwright[browserTypeName].launch(launchOptions);
+    await browser.close();
+    console.log(`(wsEndpoint=>none)`);
+    console.log(`(closed=>success)`);
+    require('http').createServer(() => {}).listen();
+    return;
+  }
+
   const browserServer = await playwright[browserTypeName].launchServer(launchOptions);
   if (disconnectOnSIGHUP)
     process.on('SIGHUP', () => browserServer._disconnectForTest());

tests/config/remoteServer.ts

@@ -68,6 +68,7 @@ export type RemoteServerOptions = {
   exitOnWarning?: boolean;
   inCluster?: boolean;
   url?: string;
+  startStopAndRunHttp?: boolean;
 };
 
 export class RemoteServer implements PlaywrightServer {
@@ -150,6 +151,10 @@ export class RemoteServer implements PlaywrightServer {
     return await this._process.exitCode;
   }
 
+  async childSignal() {
+    return (await this._process.exited).signal;
+  }
+
   async close() {
     if (this._browser) {
       await this._browser.close();

tests/library/signals.spec.ts

@@ -133,4 +133,12 @@ test.describe('signals', () => {
     expect(await remoteServer.out('signal')).toBe('SIGKILL');
     expect(await remoteServer.childExitCode()).toBe(130);
   });
+
+  test('should not prevent default SIGTERM handling after browser close', async ({ startRemoteServer, server, platform }, testInfo) => {
+    const remoteServer = await startRemoteServer('launchServer', { startStopAndRunHttp: true });
+    expect(await remoteServer.out('closed')).toBe('success');
+    process.kill(remoteServer.child().pid, 'SIGTERM');
+    expect(await remoteServer.childExitCode()).toBe(null);
+    expect(await remoteServer.childSignal()).toBe('SIGTERM');
+  });
 });