From 54294f15ef9647b5f2582b2401fc4fd87d0e49e1 Mon Sep 17 00:00:00 2001
From: John-David Dalton <john.david.dalton@gmail.com>
Date: Tue, 23 Feb 2016 08:17:55 -0800
Subject: [PATCH] Update `_.assign` and `_.assignIn` fast paths.

---
 lodash.js | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/lodash.js b/lodash.js
index 8a86e46c2..64262f9a8 100644
--- a/lodash.js
+++ b/lodash.js
@@ -10843,6 +10843,10 @@
      * // => { 'a': 1, 'c': 3, 'e': 5 }
      */
     var assign = createAssigner(function(object, source) {
+      if (nonEnumShadows || isPrototype(source) || isArrayLike(source)) {
+        copyObject(source, keys(source), object);
+        return;
+      }
       for (var key in source) {
         if (hasOwnProperty.call(source, key)) {
           assignValue(object, key, source[key]);
@@ -10850,13 +10854,6 @@
       }
     });
 
-    // Slow path for IE < 9.
-    if (nonEnumShadows) {
-      assign = createAssigner(function(object, source) {
-        copyObject(source, keys(source), object);
-      });
-    }
-
     /**
      * This method is like `_.assign` except that it iterates over own and
      * inherited source properties.
@@ -10887,18 +10884,15 @@
      * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5 }
      */
     var assignIn = createAssigner(function(object, source) {
+      if (nonEnumShadows || isPrototype(source) || isArrayLike(source)) {
+        copyObject(source, keysIn(source), object);
+        return;
+      }
       for (var key in source) {
         assignValue(object, key, source[key]);
       }
     });
 
-    // Slow path for IE < 9.
-    if (nonEnumShadows) {
-      assignIn = createAssigner(function(object, source) {
-        copyObject(source, keysIn(source), object);
-      });
-    }
-
     /**
      * This method is like `_.assignIn` except that it accepts `customizer` which
      * is invoked to produce the assigned values. If `customizer` returns `undefined`