From d0644f5444a00531517a2cd0ffec0a1364e6bdf6 Mon Sep 17 00:00:00 2001
From: Joel Einbinder <joel.einbinder@gmail.com>
Date: Tue, 21 May 2024 15:15:05 -0400
Subject: [PATCH] fix(electron): flaky startup if stderr comes in too fast
 (#30855)

Chromium's `DevTools listening on` message sometimes arrives before
Playwright is finished connecting to Node. Without this patch, it would
miss the message and fail to connect.
---
 .../playwright-core/src/server/electron/electron.ts   | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/packages/playwright-core/src/server/electron/electron.ts b/packages/playwright-core/src/server/electron/electron.ts
index 9b934ca2f7..b8f361b48a 100644
--- a/packages/playwright-core/src/server/electron/electron.ts
+++ b/packages/playwright-core/src/server/electron/electron.ts
@@ -229,6 +229,8 @@ export class Electron extends SdkObject {
         onExit: () => app?.emit(ElectronApplication.Events.Close),
       });
 
+      // All waitForLines must be started immediately.
+      // Otherwise the lines might come before we are ready.
       const waitForXserverError = new Promise(async (resolve, reject) => {
         waitForLine(progress, launchedProcess, /Unable to open X display/).then(() => reject(new Error([
           'Unable to open X display!',
@@ -240,17 +242,20 @@ export class Electron extends SdkObject {
           progress.metadata.log
         ].join('\n')))).catch(() => {});
       });
+      const nodeMatchPromise = waitForLine(progress, launchedProcess, /^Debugger listening on (ws:\/\/.*)$/);
+      const chromeMatchPromise = waitForLine(progress, launchedProcess, /^DevTools listening on (ws:\/\/.*)$/);
+      const debuggerDisconnectPromise = waitForLine(progress, launchedProcess, /Waiting for the debugger to disconnect\.\.\./);
 
-      const nodeMatch = await waitForLine(progress, launchedProcess, /^Debugger listening on (ws:\/\/.*)$/);
+      const nodeMatch = await nodeMatchPromise;
       const nodeTransport = await WebSocketTransport.connect(progress, nodeMatch[1]);
       const nodeConnection = new CRConnection(nodeTransport, helper.debugProtocolLogger(), browserLogsCollector);
 
       // Immediately release exiting process under debug.
-      waitForLine(progress, launchedProcess, /Waiting for the debugger to disconnect\.\.\./).then(() => {
+      debuggerDisconnectPromise.then(() => {
         nodeTransport.close();
       }).catch(() => {});
       const chromeMatch = await Promise.race([
-        waitForLine(progress, launchedProcess, /^DevTools listening on (ws:\/\/.*)$/),
+        chromeMatchPromise,
         waitForXserverError,
       ]) as RegExpMatchArray;
       const chromeTransport = await WebSocketTransport.connect(progress, chromeMatch[1]);