From 68372ea26b0183ce5e2c25a3a7c291195dae7d25 Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Wed, 4 May 2016 16:48:47 -0400
Subject: [PATCH] update track-by usage

---
 src/compiler/parser/index.js              | 4 +---
 test/unit/features/directives/for.spec.js | 2 +-
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/compiler/parser/index.js b/src/compiler/parser/index.js
index d946fcb8..9274d9c6 100644
--- a/src/compiler/parser/index.js
+++ b/src/compiler/parser/index.js
@@ -216,9 +216,7 @@ function processFor (el) {
       el.alias = alias
     }
     if ((exp = getAndRemoveAttr(el, 'track-by'))) {
-      el.key = exp === '$index'
-        ? exp
-        : el.alias + '["' + exp + '"]'
+      el.key = exp
     }
   }
 }
diff --git a/test/unit/features/directives/for.spec.js b/test/unit/features/directives/for.spec.js
index 085ee5b7..a5a6ea47 100644
--- a/test/unit/features/directives/for.spec.js
+++ b/test/unit/features/directives/for.spec.js
@@ -295,7 +295,7 @@ describe('Directive v-for', () => {
           { id: 3, msg: 'c' }
         ]
       },
-      template: '<div><div v-for="item in items" track-by="id">{{ item.msg }}</div></div>'
+      template: '<div><div v-for="item in items" track-by="item.id">{{ item.msg }}</div></div>'
     })
     vm.$mount()
     expect(vm.$el.textContent).toBe('abc')