fix: add a noop handler for the error event

Backported from main: 15af22f

lib/socket.js

@@ -49,6 +49,8 @@ var flags = [
 
 var emit = Emitter.prototype.emit;
 
+function noop() {}
+
 /**
  * Interface to a `Client` for a given `Namespace`.
  *
@@ -72,6 +74,9 @@ function Socket(nsp, client, query){
   this.fns = [];
   this.flags = {};
   this._rooms = [];
+
+  // prevents crash when the socket receives an "error" event without listener
+  this.on('error', noop);
 }
 
 /**
@@ -427,12 +432,7 @@ Socket.prototype.ondisconnect = function(){
  */
 
 Socket.prototype.onerror = function(err){
-  if (this.listeners('error').length) {
-    this.emit('error', err);
-  } else {
-    console.error('Missing error handler on `socket`.');
-    console.error(err.stack);
-  }
+  this.emit('error', err);
 };
 
 /**