From d251b4de879fbd6828d1208083b6411389141645 Mon Sep 17 00:00:00 2001
From: Erik Little <nuclear.ace@gmail.com>
Date: Wed, 8 Nov 2017 08:17:36 -0500
Subject: [PATCH] Fix #855

---
 Source/SocketIO/Engine/SocketEngine.swift | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Source/SocketIO/Engine/SocketEngine.swift b/Source/SocketIO/Engine/SocketEngine.swift
index bed0204..ead8671 100644
--- a/Source/SocketIO/Engine/SocketEngine.swift
+++ b/Source/SocketIO/Engine/SocketEngine.swift
@@ -536,8 +536,11 @@ public final class SocketEngine : NSObject, URLSessionDelegate, SocketEnginePoll
         pongsMissed += 1
         write("", withType: .ping, withData: [])
 
-        engineQueue.asyncAfter(deadline: DispatchTime.now() + .milliseconds(pingInterval)) {[weak self] in
-            self?.sendPing()
+        engineQueue.asyncAfter(deadline: DispatchTime.now() + .milliseconds(pingInterval)) {[weak self, id = self.sid] in
+            // Make sure not to ping old connections
+            guard let this = self, this.sid == id else { return }
+
+            this.sendPing()
         }
 
         client?.engineDidSendPing()