From 5817877aa100f4aecb6a8f0c021d20423e34a668 Mon Sep 17 00:00:00 2001
From: Matthew Creager <mattcreager@goinstant.com>
Date: Mon, 28 Apr 2014 14:08:20 -0300
Subject: [PATCH] fix(key_sync): optimize model updates

Removing dead properties and adding new properties now occurs within
a single `$timeout`.

Closes: #95
Signed-off-by: Colin MacDonald <colin@goinstant.com>
---
 lib/key_sync.js | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/lib/key_sync.js b/lib/key_sync.js
index 508749b..8319dc2 100644
--- a/lib/key_sync.js
+++ b/lib/key_sync.js
@@ -103,16 +103,6 @@ KeySync.prototype.$$handleUpdate = function(value, context) {
 
   value = normalize(_.cloneDeep(value), context);
 
-  if (context.command === 'SET' && targetKey === context.currentKey) {
-    self.$timeout(function() {
-      _.each(self.$$model, function(value, key, model) {
-        if (_.first(key) !== '$') {
-          delete model[key];
-        }
-      });
-    });
-  }
-
   if (context.command === 'SET' && targetKey !== context.currentKey) {
     // Determine the relative path between the key we are listening too and the
     // origin of the event.
@@ -151,8 +141,19 @@ KeySync.prototype.$$handleUpdate = function(value, context) {
   }
 
   self.$timeout(function() {
+    if (context.command === 'SET' && targetKey === context.currentKey) {
+      _.each(self.$$model, function(value, key, model) {
+        if (_.first(key) !== '$') {
+          delete model[key];
+        }
+      });
+    }
+
     _.merge(self.$$model, value);
-    delete self.$$model.$value;
+
+    if (self.$$model.$value) {
+      delete self.$$model.$value;
+    }
   });
 };