fix(WebSocket): don't patch EventTarget methods twice

tlancina · vicb · commit 345e56c7ba71 · 2016-01-27T10:19:45.000-08:00
closes #235 On older versions of Chrome, patching via property descriptors isn't available, but unlike Safari, window.EventTarget exists and is already patched, so the EventTarget methods on WebSocket.prototype don't need to be patched again. Closes #233.
diff --git a/lib/patch/websocket.ts b/lib/patch/websocket.ts
@@ -3,7 +3,11 @@ import * as utils from '../utils';
 // we have to patch the instance since the proto is non-configurable
 export function apply() {
   var WS = (<any>global).WebSocket;
-  utils.patchEventTargetMethods(WS.prototype);
+  // On Safari window.EventTarget doesn't exist so need to patch WS add/removeEventListener
+  // On older Chrome, no need since EventTarget was already patched
+  if (!(<any>global).EventTarget) {
+    utils.patchEventTargetMethods(WS.prototype);
+  }
   (<any>global).WebSocket = function(a, b) {
     var socket = arguments.length > 1 ? new WS(a, b) : new WS(a);
     var proxySocket;
