From d89787d6c35c8162a6cecf278601707d769e4884 Mon Sep 17 00:00:00 2001
From: Andrey Lushnikov <lushnikov@chromium.org>
Date: Thu, 13 Feb 2020 12:15:22 -0800
Subject: [PATCH 1/2] fix(webkit): avoid UnhandledPromiseRejection

If we close a browser before sending first websocket message,
the `this._connect` promise will reject and will not be handled.

This surfaced at https://github.com/microsoft/playwright/pull/976/checks?check_run_id=444445350
---
 src/platform.ts | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/platform.ts b/src/platform.ts
index b4c0fea7baade..0624db79c26ae 100644
--- a/src/platform.ts
+++ b/src/platform.ts
@@ -316,16 +316,16 @@ export class WebSocketTransport implements ConnectionTransport {
 
   onmessage?: (message: string) => void;
   onclose?: () => void;
-  private _connect: Promise<void>;
+  private _connectPromise: Promise<(Error|null)>;
 
   constructor(url: string) {
     this._ws = (isNode ? new NodeWebSocket(url, [], {
       perMessageDeflate: false,
       maxPayload: 256 * 1024 * 1024, // 256Mb
     }) : new WebSocket(url)) as WebSocket;
-    this._connect = new Promise((fulfill, reject) => {
-      this._ws.addEventListener('open', () => fulfill());
-      this._ws.addEventListener('error', event => reject(new Error('WebSocket error: ' + (event as ErrorEvent).message)));
+    this._connectPromise = new Promise((fulfill => {
+      this._ws.addEventListener('open', () => fulfill(null));
+      this._ws.addEventListener('error', event => fulfill(new Error('WebSocket error: ' + (event as ErrorEvent).message)));
     });
     // The 'ws' module in node sometimes sends us multiple messages in a single task.
     // In Web, all IO callbacks (e.g. WebSocket callbacks)
@@ -349,7 +349,9 @@ export class WebSocketTransport implements ConnectionTransport {
   }
 
   async send(message: string) {
-    await this._connect;
+    const error = await this._connectPromise;
+    if (error)
+      throw error;
     this._ws.send(message);
   }
 

From 8a57c208be8b791c506d2e1f9c15fbb4a9204d83 Mon Sep 17 00:00:00 2001
From: Andrey Lushnikov <lushnikov@chromium.org>
Date: Thu, 13 Feb 2020 12:17:15 -0800
Subject: [PATCH 2/2] fix

---
 src/platform.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/platform.ts b/src/platform.ts
index 0624db79c26ae..7015b895193c4 100644
--- a/src/platform.ts
+++ b/src/platform.ts
@@ -323,7 +323,7 @@ export class WebSocketTransport implements ConnectionTransport {
       perMessageDeflate: false,
       maxPayload: 256 * 1024 * 1024, // 256Mb
     }) : new WebSocket(url)) as WebSocket;
-    this._connectPromise = new Promise((fulfill => {
+    this._connectPromise = new Promise(fulfill => {
       this._ws.addEventListener('open', () => fulfill(null));
       this._ws.addEventListener('error', event => fulfill(new Error('WebSocket error: ' + (event as ErrorEvent).message)));
     });