Guard property access to __raven_wrapper__ (#720)

Author: scothis

src/raven.js

@@ -258,18 +258,18 @@ Raven.prototype = {
             if (func.__raven__) {
                 return func;
             }
+
+            // If this has already been wrapped in the past, return that
+            if (func.__raven_wrapper__ ){
+                return func.__raven_wrapper__ ;
+            }
         } catch (e) {
-            // Just accessing the __raven__ prop in some Selenium environments
+            // Just accessing custom props in some Selenium environments
             // can cause a "Permission denied" exception (see raven-js#495).
             // Bail on wrapping and return the function as-is (defers to window.onerror).
             return func;
         }
 
-        // If this has already been wrapped in the past, return that
-        if (func.__raven_wrapper__ ){
-            return func.__raven_wrapper__ ;
-        }
-
         function wrapped() {
             var args = [], i = arguments.length,
                 deep = !options || options && options.deep !== false;
@@ -864,7 +864,11 @@ Raven.prototype = {
                 }, wrappedBuiltIns);
                 fill(proto, 'removeEventListener', function (orig) {
                     return function (evt, fn, capture, secure) {
-                        fn = fn && (fn.__raven_wrapper__ ? fn.__raven_wrapper__  : fn);
+                        try {
+                            fn = fn && (fn.__raven_wrapper__ ? fn.__raven_wrapper__  : fn);
+                        } catch (e) {
+                            // ignore, accessing __raven_wrapper__ will throw in some Selenium environments
+                        }
                         return orig.call(this, evt, fn, capture, secure);
                     };
                 }, wrappedBuiltIns);

test/raven.test.js

@@ -1735,6 +1735,19 @@ describe('Raven (public API)', function() {
             assert.equal(fn, wrapped);
         });
 
+        it('should return input funciton as-is if accessing __raven_wrapper__ prop throws exception', function (){
+            // see raven-js#495
+            var fn = function () {};
+            Object.defineProperty(fn, '__raven_wrapper__', {
+              get: function () {
+                  throw new Error('Permission denied')
+              }
+            });
+            assert.throw(function () { fn.__raven_wrapper__; }, 'Permission denied');
+            var wrapped = Raven.wrap(fn);
+            assert.equal(fn, wrapped);
+        });
+
     });
 
     describe('.context', function() {