Fixes #2151 Problem when valueAllowUnset is true and option value is …

…0 and model value is null
knockout · Dec 3, 2016 · 2f230dc · 2f230dc
1 parent cdd2741
commit 2f230dc
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Showing 2 changed files with 14 additions and 1 deletion.
diff --git a/spec/defaultBindings/valueBehaviors.js b/spec/defaultBindings/valueBehaviors.js
@@ -641,6 +641,19 @@ describe('Binding: Value', function() {
                 expect(testNode.childNodes[0].selectedIndex).toEqual(-1);
                 expect(selected()).toEqual("B");
             });
+
+            it('Should select no options if model value is null and option value is 0', function() {
+                var observable = ko.observable(null);
+                var options = [
+                    { name: 'B', id: 1 },
+                    { name: 'A', id: 0 }
+                ];
+                testNode.innerHTML = "<select data-bind='options:options, optionsValue:\"id\", optionsText:\"name\", value:myObservable, valueAllowUnset:true'></select>";
+                ko.applyBindings({ myObservable: observable, options: options }, testNode);
+
+                expect(testNode.childNodes[0].selectedIndex).toEqual(-1);
+                expect(observable()).toEqual(undefined);
+            });
         });
     });
 

diff --git a/src/binding/selectExtensions.js b/src/binding/selectExtensions.js
@@ -48,7 +48,7 @@
                     for (var i = 0, n = element.options.length, optionValue; i < n; ++i) {
                         optionValue = ko.selectExtensions.readValue(element.options[i]);
                         // Include special check to handle selecting a caption with a blank string value
-                        if (optionValue == value || (optionValue == "" && value === undefined)) {
+                        if (optionValue == value || (optionValue === "" && value === undefined)) {
                             selection = i;
                             break;
                         }