From 66d64b332190be1277c14e3e28431d8e8e32de44 Mon Sep 17 00:00:00 2001
From: Caitlin Potter <caitpotter88@gmail.com>
Date: Tue, 6 May 2014 22:57:31 -0400
Subject: [PATCH] fix(ngSwitch): properly support case labels with different
 numbers of transclude fns

Due to a regression introduced several releases ago, the ability for multiple transclude functions
to work correctly changed, as they would break if different case labels had different numbers of
transclude functions.

This CL corrects this by not assuming that previous elements and scope count have the same length.
---
 src/ng/directive/ngSwitch.js      | 42 +++++++++++++------------------
 test/ng/directive/ngSwitchSpec.js | 23 +++++++++++++++++
 2 files changed, 40 insertions(+), 25 deletions(-)

diff --git a/src/ng/directive/ngSwitch.js b/src/ng/directive/ngSwitch.js
index 312cdf728b0f..e34b89b0dafb 100644
--- a/src/ng/directive/ngSwitch.js
+++ b/src/ng/directive/ngSwitch.js
@@ -138,37 +138,29 @@ var ngSwitchDirective = ['$animate', function($animate) {
     }],
     link: function(scope, element, attr, ngSwitchController) {
       var watchExpr = attr.ngSwitch || attr.on,
-          selectedTranscludes,
-          selectedElements,
-          previousElements,
+          selectedTranscludes = [],
+          selectedElements = [],
+          previousElements = [],
           selectedScopes = [];
 
       scope.$watch(watchExpr, function ngSwitchWatchAction(value) {
-        var i, ii = selectedScopes.length;
-        if(ii > 0) {
-          if(previousElements) {
-            for (i = 0; i < ii; i++) {
-              previousElements[i].remove();
-            }
-            previousElements = null;
-          }
+        var i, ii;
+        for (i = 0, ii = previousElements.length; i < ii; ++i) {
+          previousElements[i].remove();
+        }
+        previousElements.length = 0;
 
-          previousElements = [];
-          for (i= 0; i<ii; i++) {
-            var selected = selectedElements[i];
-            selectedScopes[i].$destroy();
-            previousElements[i] = selected;
-            $animate.leave(selected, function() {
-              previousElements.splice(i, 1);
-              if(previousElements.length === 0) {
-                previousElements = null;
-              }
-            });
-          }
+        for (i = 0, ii = selectedScopes.length; i < ii; ++i) {
+          var selected = selectedElements[i];
+          selectedScopes[i].$destroy();
+          previousElements[i] = selected;
+          $animate.leave(selected, function() {
+            previousElements.splice(i, 1);
+          });
         }
 
-        selectedElements = [];
-        selectedScopes = [];
+        selectedElements.length = 0;
+        selectedScopes.length = 0;
 
         if ((selectedTranscludes = ngSwitchController.cases['!' + value] || ngSwitchController.cases['?'])) {
           scope.$eval(attr.change);
diff --git a/test/ng/directive/ngSwitchSpec.js b/test/ng/directive/ngSwitchSpec.js
index 60193adcde2e..9044147e139c 100644
--- a/test/ng/directive/ngSwitchSpec.js
+++ b/test/ng/directive/ngSwitchSpec.js
@@ -212,6 +212,29 @@ describe('ngSwitch', function() {
     // element now contains only empty repeater. this element is dealocated by local afterEach.
     // afterwards a global afterEach will check for leaks in jq data cache object
   }));
+
+
+  it('should properly support case labels with different numbers of transclude fns', inject(function($rootScope, $compile) {
+    element = $compile(
+      '<div ng-switch="mode">' +
+        '<p ng-switch-when="a">Block1</p>' +
+        '<p ng-switch-when="a">Block2</p>' +
+        '<a href ng-switch-when="b">a</a>' +
+      '</div>'
+    )($rootScope);
+
+    $rootScope.$apply('mode = "a"');
+    expect(element.children().length).toBe(2);
+
+    $rootScope.$apply('mode = "b"');
+    expect(element.children().length).toBe(1);
+
+    $rootScope.$apply('mode = "a"');
+    expect(element.children().length).toBe(2);
+
+    $rootScope.$apply('mode = "b"');
+    expect(element.children().length).toBe(1);
+  }));
 });
 
 describe('ngSwitch animations', function() {