fix: avoid waiting for inherited Edge stdio

packages/playwright-core/src/server/browserType.ts

@@ -225,6 +225,7 @@ export abstract class BrowserType extends SdkObject {
         browserLogsCollector.log(message);
       },
       stdio: 'pipe',
+      waitForStdioClose: !this.getExecutableName(options).startsWith('msedge'),
       tempDirectories: prepared.tempDirectories,
       attemptToGracefullyClose: async () => {
         if ((options as any).__testHookGracefullyClose)

packages/utils/processLauncher.ts

@@ -32,6 +32,9 @@ export type LaunchProcessOptions = {
   handleSIGTERM?: boolean,
   handleSIGHUP?: boolean,
   stdio: 'pipe' | 'stdin',
+  // Defaults to true. Set to false when a child process can spawn helpers
+  // that inherit stdio and outlive the child itself.
+  waitForStdioClose?: boolean,
   tempDirectories: string[],
 
   cwd?: string,
@@ -179,10 +182,11 @@ export async function launchProcess(options: LaunchProcessOptions): Promise<Laun
     options.log(`[pid=${spawnedProcess.pid}][err] ` + data);
   });
 
+  const waitForStdioClose = options.waitForStdioClose ?? true;
   let processClosed = false;
   let fulfillCleanup = () => {};
   const waitForCleanup = new Promise<void>(f => fulfillCleanup = f);
-  spawnedProcess.once('close', (exitCode, signal) => {
+  const handleProcessExit = (exitCode: number | null, signal: string | null) => {
     options.log(`[pid=${spawnedProcess.pid}] <process did exit: exitCode=${exitCode}, signal=${signal}>`);
     processClosed = true;
     gracefullyCloseSet.delete(gracefullyClose);
@@ -191,7 +195,8 @@ export async function launchProcess(options: LaunchProcessOptions): Promise<Laun
     options.onExit(exitCode, signal);
     // Cleanup as process exits.
     cleanup().then(fulfillCleanup);
-  });
+  };
+  spawnedProcess.once(waitForStdioClose ? 'close' : 'exit', handleProcessExit);
 
   addProcessHandlerIfNeeded('exit');
   if (options.handleSIGINT)

tests/playwright-test/process-launcher.spec.ts

@@ -0,0 +1,91 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { test, expect } from './playwright-test-fixtures';
+import fs from 'fs';
+import { utils } from '../../packages/playwright-core/lib/coreBundle';
+
+const { launchProcess } = utils;
+
+async function launchProcessWithStdioGrandchild(pidFile: string, cleanupDir: string, waitForStdioClose: boolean) {
+  fs.mkdirSync(cleanupDir, { recursive: true });
+  let onExitCalls = 0;
+  const script = `
+    const { spawn } = require('child_process');
+    const fs = require('fs');
+    const child = spawn(process.execPath, ['-e', 'setTimeout(() => {}, 30000)'], { stdio: 'inherit' });
+    fs.writeFileSync(process.argv[1], String(child.pid));
+    child.unref();
+  `;
+  const result = await launchProcess({
+    command: process.execPath,
+    args: ['-e', script, pidFile],
+    stdio: 'pipe',
+    waitForStdioClose,
+    tempDirectories: [cleanupDir],
+    attemptToGracefullyClose: async () => {},
+    handleSIGINT: false,
+    handleSIGTERM: false,
+    handleSIGHUP: false,
+    log: () => {},
+    onExit: () => ++onExitCalls,
+  });
+  return { ...result, onExitCalls: () => onExitCalls };
+}
+
+function killGrandchild(pidFile: string) {
+  if (!fs.existsSync(pidFile))
+    return;
+  const pid = +fs.readFileSync(pidFile, 'utf8');
+  try {
+    process.kill(pid, 'SIGKILL');
+  } catch (e) {
+  }
+}
+
+test('process launcher can wait for the main process exit without waiting for inherited stdio', async ({}, testInfo) => {
+  const pidFile = testInfo.outputPath('grandchild.pid');
+  const cleanupDir = testInfo.outputPath('cleanup');
+  const { gracefullyClose, onExitCalls } = await launchProcessWithStdioGrandchild(pidFile, cleanupDir, false);
+  try {
+    const start = Date.now();
+    await gracefullyClose();
+    expect(Date.now() - start).toBeLessThan(1000);
+    expect(onExitCalls()).toBe(1);
+    expect(fs.existsSync(cleanupDir)).toBe(false);
+  } finally {
+    killGrandchild(pidFile);
+  }
+});
+
+test('process launcher waits for stdio close by default', async ({}, testInfo) => {
+  const pidFile = testInfo.outputPath('grandchild.pid');
+  const cleanupDir = testInfo.outputPath('cleanup');
+  const { gracefullyClose, onExitCalls } = await launchProcessWithStdioGrandchild(pidFile, cleanupDir, true);
+  const closePromise = gracefullyClose();
+  try {
+    const closed = await Promise.race([
+      closePromise.then(() => true),
+      new Promise<boolean>(f => setTimeout(() => f(false), 1000)),
+    ]);
+    expect(closed).toBe(false);
+  } finally {
+    killGrandchild(pidFile);
+    await closePromise;
+    expect(onExitCalls()).toBe(1);
+    expect(fs.existsSync(cleanupDir)).toBe(false);
+  }
+});