From dd597d21973c0119147be806199d2d415ffc0b5c Mon Sep 17 00:00:00 2001
From: Ritchie Martori <skawful@gmail.com>
Date: Thu, 20 Feb 2014 17:25:07 -0800
Subject: [PATCH] Refactor mixin and always redefine proxy/delegate methods

---
 lib/jutil.js | 54 ++++++++++++++++++++++++++--------------------------
 1 file changed, 27 insertions(+), 27 deletions(-)

diff --git a/lib/jutil.js b/lib/jutil.js
index 03e21500..c33ec24c 100644
--- a/lib/jutil.js
+++ b/lib/jutil.js
@@ -55,39 +55,39 @@ exports.mixin = function (newClass, mixinClass, options) {
   }
 
   if (options.staticProperties) {
-    var staticProxies = [];
-    Object.keys(mixinClass).forEach(function (classProp) {
-      if (classProp !== 'super_' && classProp !== '_mixins'
-        && (!newClass.hasOwnProperty(classProp) || options.override)) {
-        var pd = Object.getOwnPropertyDescriptor(mixinClass, classProp);
-        if (options.proxyFunctions && pd.writable
-          && typeof pd.value === 'function') {
-          pd.value = exports.proxy(pd.value, staticProxies);
-        }
-        Object.defineProperty(newClass, classProp, pd);
-      }
-    });
+    mixInto(mixinClass, newClass, options);
   }
 
-  if (options.instanceProperties) {
-    if (mixinClass.prototype) {
-      var instanceProxies = [];
-      Object.keys(mixinClass.prototype).forEach(function (instanceProp) {
-        if (!newClass.prototype.hasOwnProperty(instanceProp) || options.override) {
-          var pd = Object.getOwnPropertyDescriptor(mixinClass.prototype, instanceProp);
-          if (options.proxyFunctions && pd.writable && typeof pd.value === 'function') {
-            pd.value = exports.proxy(pd.value, instanceProxies);
-          }
-          Object.defineProperty(newClass.prototype, instanceProp, pd);
-        }
-      });
-    }
+  if (options.instanceProperties && mixinClass.prototype) {
+    mixInto(mixinClass.prototype, newClass.prototype, options);
   }
-
+  
   return newClass;
 };
 
-exports.proxy = function (fn, proxies) {
+function mixInto(sourceScope, targetScope, options) {
+  var proxies = [];
+
+  Object.keys(sourceScope).forEach(function (propertyName, options) {
+    var targetPropertyExists = targetScope.hasOwnProperty(propertyName);
+    var sourceProperty = Object.getOwnPropertyDescriptor(sourceScope, propertyName);
+    var targetProperty = targetPropertyExists && Object.getOwnPropertyDescriptor(targetScope, propertyName);
+    var sourceIsFunc = typeof sourceProperty.value === 'function';
+    var isFunc = targetPropertyExists && typeof targetProperty.value === 'function';
+    var isDelegate = isFunc && targetProperty.value._delegate;
+    var shouldOverride = options.override || !targetPropertyExists || isDelegate;
+
+    if (shouldOverride) {
+      if (sourceIsFunc) {
+        sourceProperty.value = exports.proxy(sourceProperty.value, proxies);
+      }
+      
+      Object.defineProperty(targetScope, propertyName, sourceProperty);
+    }
+  });
+}
+
+exports.proxy = function createProxy(fn, proxies) {
   // Make sure same methods referenced by different properties have the same proxy
   // For example, deleteById is an alias of removeById
   proxies = proxies || [];