From 48a5666c639803c3a0d8c9113a1551f6aaed1042 Mon Sep 17 00:00:00 2001
From: Jan Varwig <jan@varwig.org>
Date: Fri, 8 Aug 2014 16:28:57 +0200
Subject: [PATCH] fix(select): Add exception for unsupported ngOptions use case

ngOptions introduced `track by` in c32a859bdb93699cc080f9affed4bcff63005a64.
Using `track by` puts constraints on the value you can use in the interpolation
expression in ngOptions. This patch adds an exception
if you use ngOptions in an unsupported way.
---
 src/ng/directive/select.js      | 6 ++++++
 test/ng/directive/selectSpec.js | 9 +++++++++
 2 files changed, 15 insertions(+)

diff --git a/src/ng/directive/select.js b/src/ng/directive/select.js
index 852fcef639aa..b8bf240b086c 100644
--- a/src/ng/directive/select.js
+++ b/src/ng/directive/select.js
@@ -338,6 +338,12 @@ var selectDirective = ['$compile', '$parse', function($compile,   $parse) {
             // - optionGroupsCache[?][0] is the parent: either the SELECT or OPTGROUP element
             optionGroupsCache = [[{element: selectElement, label:''}]];
 
+        if (track && match[2] && valueName !== match[1]) {
+          throw ngOptionsMinErr('trackSelect',
+            "Do not use 'track by' when your select ('{0}') is different from your value ('{1}')",
+            match[1], valueName);
+        }
+
         if (nullOption) {
           // compile the element since there might be bindings in it
           $compile(nullOption)(scope);
diff --git a/test/ng/directive/selectSpec.js b/test/ng/directive/selectSpec.js
index e896dc05836d..c5c1ca0cf1c5 100644
--- a/test/ng/directive/selectSpec.js
+++ b/test/ng/directive/selectSpec.js
@@ -877,6 +877,15 @@ describe('select', function() {
         expect(element.val()).toEqual('4');
       });
 
+      it('should throw an error when trying to combine track by with a complex select expression', function() {
+        expect(function() {
+          createSelect({
+            'ng-model': 'selected',
+            'ng-options': 'item.id as item.name for item in values track by item.id'
+          });
+        }).toThrowMinErr('ngOptions','trackSelect', "Do not use 'track by' when your select ('item.id') is different from your value ('item')");
+      });
+
 
       it('should bind to scope value through experession', function() {
         createSelect({