From b6fb9c356620775c074a2f04be880c7c7472b788 Mon Sep 17 00:00:00 2001
From: robw <rob.whitehead@gmail.com>
Date: Tue, 8 Dec 2015 15:38:50 -0800
Subject: [PATCH 1/3] feat(ngOptions): add ngEmptyValue attribute to ngOptions

allow an optional ng-empty-value attribute on select elements using ng-options. any option whose value is an empty string will be replaced with the given empty-value.

Closes: #13334
---
 src/ng/directive/ngOptions.js      |  9 +++++++++
 test/ng/directive/ngOptionsSpec.js | 20 ++++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/src/ng/directive/ngOptions.js b/src/ng/directive/ngOptions.js
index 7f1e13ec32f4..f2a849afe163 100644
--- a/src/ng/directive/ngOptions.js
+++ b/src/ng/directive/ngOptions.js
@@ -31,6 +31,9 @@ var ngOptionsMinErr = minErr('ngOptions');
  * be nested into the `<select>` element. This element will then represent the `null` or "not selected"
  * option. See example below for demonstration.
  *
+ * Additionally, a default value can be specified for empty options using the `ng-empty-value` attribute.
+ * See Usage section for more details.
+ *
  * ## Complex Models (objects or collections)
  *
  * By default, `ngModel` watches the model by reference, not value. This is important to know when
@@ -156,6 +159,9 @@ var ngOptionsMinErr = minErr('ngOptions');
  *     `value` variable (e.g. `value.propertyName`). With this the selection is preserved
  *      even when the options are recreated (e.g. reloaded from the server).
  *
+ * @param {expression=} ngEmptyValue When an option with empty value is selected, whether hardcoded or created
+ *    with ngOptions, the associated ngModel will be assigned the result of this expression.
+ *
  * @example
     <example module="selectExample">
       <file name="index.html">
@@ -489,6 +495,9 @@ var ngOptionsDirective = ['$compile', '$parse', function($compile, $parse) {
 
         selectCtrl.readValue = function readNgOptionsValue() {
 
+          // Allow a default value to be substituted for any options with empty values
+          if (selectElement.val() === '') return $parse(attr.ngEmptyValue)(scope);
+
           var selectedOption = options.selectValueMap[selectElement.val()];
 
           if (selectedOption && !selectedOption.disabled) {
diff --git a/test/ng/directive/ngOptionsSpec.js b/test/ng/directive/ngOptionsSpec.js
index 0edbabe1459d..b9c00895f2ff 100644
--- a/test/ng/directive/ngOptionsSpec.js
+++ b/test/ng/directive/ngOptionsSpec.js
@@ -2143,6 +2143,26 @@ describe('ngOptions', function() {
       expect(scope.selected).toEqual([]);
     });
 
+    it('should be possible to specify a value for empty options', function() {
+      var html = '<select ng-model="someModel" ng-options="c for c in choices" ng-empty-value="someVar">' +
+                   '<option value="">Choose One</option>' +
+                 '</select>';
+      compile(html);
+      scope.$apply(function() {
+        scope.choices = ['A','B','C'];
+        scope.someModel = "";
+        scope.someVar = "foo";
+      });
+      //current implementation only works if select is not pristine, so we click it back and forth
+      setSelectValue(element, 3);
+      setSelectValue(element, 0);
+
+      //make sure the empty value is being evaluated as an Angular expression
+      expect(scope.someModel).toBe("foo");
+
+      dealoc(element);
+
+    });
 
     it('should be possible to use ngIf in the blank option', function() {
       var option;

From df89869cb26302ad9cb043166b8097ef5c6eea5b Mon Sep 17 00:00:00 2001
From: robw <rob.whitehead@gmail.com>
Date: Tue, 15 Dec 2015 14:22:27 -0800
Subject: [PATCH 2/3] changes in response to notes in PR thread -- to be
 squashed later

---
 src/ng/directive/ngOptions.js      |  4 +++-
 test/ng/directive/ngOptionsSpec.js | 24 +++++++++++++++++-------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/src/ng/directive/ngOptions.js b/src/ng/directive/ngOptions.js
index f2a849afe163..410051f50ca4 100644
--- a/src/ng/directive/ngOptions.js
+++ b/src/ng/directive/ngOptions.js
@@ -493,10 +493,12 @@ var ngOptionsDirective = ['$compile', '$parse', function($compile, $parse) {
           }
         };
 
+        var emptyValueParseFn = 'ngEmptyValue' in attr && attr.ngEmptyValue.length > 0 && $parse(attr.ngEmptyValue);
+
         selectCtrl.readValue = function readNgOptionsValue() {
 
           // Allow a default value to be substituted for any options with empty values
-          if (selectElement.val() === '') return $parse(attr.ngEmptyValue)(scope);
+          if (selectElement.val() === '' && emptyValueParseFn) return emptyValueParseFn(scope);
 
           var selectedOption = options.selectValueMap[selectElement.val()];
 
diff --git a/test/ng/directive/ngOptionsSpec.js b/test/ng/directive/ngOptionsSpec.js
index b9c00895f2ff..0d1ec1663d4a 100644
--- a/test/ng/directive/ngOptionsSpec.js
+++ b/test/ng/directive/ngOptionsSpec.js
@@ -2144,13 +2144,15 @@ describe('ngOptions', function() {
     });
 
     it('should be possible to specify a value for empty options', function() {
-      var html = '<select ng-model="someModel" ng-options="c for c in choices" ng-empty-value="someVar">' +
-                   '<option value="">Choose One</option>' +
-                 '</select>';
-      compile(html);
+      createSelect({
+        'ng-model':'selected',
+        'ng-empty-value': 'someVar',
+        'ng-options':'c for c in choices'
+      }, true);
+
       scope.$apply(function() {
         scope.choices = ['A','B','C'];
-        scope.someModel = "";
+        scope.selected = "";
         scope.someVar = "foo";
       });
       //current implementation only works if select is not pristine, so we click it back and forth
@@ -2158,9 +2160,17 @@ describe('ngOptions', function() {
       setSelectValue(element, 0);
 
       //make sure the empty value is being evaluated as an Angular expression
-      expect(scope.someModel).toBe("foo");
+      expect(scope.selected).toBe("foo");
 
-      dealoc(element);
+      //make sure a change to the value given in ng-empty-value also changes the model
+      scope.$apply(function() {
+        scope.someVar = "bar";
+      });
+
+      setSelectValue(element, 3);
+      setSelectValue(element, 0);
+
+      expect(scope.selected).toBe("bar");
 
     });
 

From 0a5306166652c80a2af932e27f7939f397441889 Mon Sep 17 00:00:00 2001
From: robw <rob.whitehead@gmail.com>
Date: Tue, 15 Dec 2015 14:42:37 -0800
Subject: [PATCH 3/3] split line for linter

---
 src/ng/directive/ngOptions.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/ng/directive/ngOptions.js b/src/ng/directive/ngOptions.js
index 410051f50ca4..b5ce45475b02 100644
--- a/src/ng/directive/ngOptions.js
+++ b/src/ng/directive/ngOptions.js
@@ -493,7 +493,8 @@ var ngOptionsDirective = ['$compile', '$parse', function($compile, $parse) {
           }
         };
 
-        var emptyValueParseFn = 'ngEmptyValue' in attr && attr.ngEmptyValue.length > 0 && $parse(attr.ngEmptyValue);
+        var emptyValueParseFn = 'ngEmptyValue' in attr && attr.ngEmptyValue.length > 0
+                                && $parse(attr.ngEmptyValue);
 
         selectCtrl.readValue = function readNgOptionsValue() {