Added possibility of overriding notifySubscribers

micromata · Dec 12, 2011 · 2b978e6 · 2b978e6
1 parent eef5fd3
commit 2b978e6
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Showing 7 changed files with 117 additions and 90 deletions.
diff --git a/build/output/knockout-latest.debug.js b/build/output/knockout-latest.debug.js
@@ -748,7 +748,6 @@ ko.subscribable = function () {
     ko.utils.extend(this, ko.subscribable['fn']);
     ko.exportProperty(this, 'subscribe', this.subscribe);
     ko.exportProperty(this, 'extend', this.extend);
-    ko.exportProperty(this, 'notifySubscribers', this.notifySubscribers);
     ko.exportProperty(this, 'getSubscriptionsCount', this.getSubscriptionsCount);
 }
 
@@ -769,7 +768,7 @@ ko.subscribable['fn'] = {
         return subscription;
     },
 
-    notifySubscribers: function (valueToNotify, event) {
+    "notifySubscribers": function (valueToNotify, event) {
         event = event || defaultEvent;
         if (this._subscriptions[event]) {
             ko.utils.arrayForEach(this._subscriptions[event].slice(0), function (subscription) {
@@ -795,7 +794,7 @@ ko.subscribable['fn'] = {
 
 
 ko.isSubscribable = function (instance) {
-    return typeof instance.subscribe == "function" && typeof instance.notifySubscribers == "function";
+    return typeof instance.subscribe == "function" && typeof instance["notifySubscribers"] == "function";
 };
 
 ko.exportSymbol('ko.subscribable', ko.subscribable);
@@ -849,8 +848,8 @@ ko.observable = function (initialValue) {
         }
     }
     ko.subscribable.call(observable);
-    observable.valueHasMutated = function () { observable.notifySubscribers(_latestValue); }
-    observable.valueWillMutate = function () { observable.notifySubscribers(_latestValue, "beforeChange"); }
+    observable.valueHasMutated = function () { observable["notifySubscribers"](_latestValue); }
+    observable.valueWillMutate = function () { observable["notifySubscribers"](_latestValue, "beforeChange"); }
     ko.utils.extend(observable, ko.observable['fn']);
 
     ko.exportProperty(observable, "valueHasMutated", observable.valueHasMutated);
@@ -1082,13 +1081,13 @@ ko.dependentObservable = function (evaluatorFunctionOrOptions, evaluatorFunction
             });
             var valueForThis = options["owner"] || evaluatorFunctionTarget; // If undefined, it will default to "window" by convention. This might change in the future.
             var newValue = options["read"].call(valueForThis);
-            dependentObservable.notifySubscribers(_latestValue, "beforeChange");
+            dependentObservable["notifySubscribers"](_latestValue, "beforeChange");
             _latestValue = newValue;
         } finally {
             ko.dependencyDetection.end();
         }
 
-        dependentObservable.notifySubscribers(_latestValue);
+        dependentObservable["notifySubscribers"](_latestValue);
         _hasBeenEvaluated = true;
     }
 

diff --git a/build/output/knockout-latest.js b/build/output/knockout-latest.js
diff --git a/spec/observableBehaviors.js b/spec/observableBehaviors.js
@@ -211,5 +211,21 @@ describe('Observable', {
         // undefined vs object - change
         instance({ id: 1 });
         value_of(notifiedValues.length).should_be(5);
-    }    
+    },
+
+    'Should be possible to replace notifySubscribers with a custom handler': function() {
+        var instance = new ko.observable(123);
+        var interceptedNotifications = [];
+        instance.subscribe(function() { throw new Error("Should not notify subscribers by default once notifySubscribers is overridden") });
+        instance.notifySubscribers = function(newValue, eventName) {
+            interceptedNotifications.push({ eventName: eventName || "None", value: newValue });
+        };
+        instance(456);
+
+        value_of(interceptedNotifications.length).should_be(2);
+        value_of(interceptedNotifications[0].eventName).should_be("beforeChange");
+        value_of(interceptedNotifications[1].eventName).should_be("None");
+        value_of(interceptedNotifications[0].value).should_be(123);
+        value_of(interceptedNotifications[1].value).should_be(456);
+    }
 });
diff --git a/spec/subscribableBehaviors.js b/spec/subscribableBehaviors.js
@@ -83,5 +83,19 @@ describe('Subscribable', {
         instance.subscribe(function() { });
         instance.subscribe(function() { }, null, "someSpecificEvent");
         value_of(instance.getSubscriptionsCount()).should_be(2);
-    }
+    },
+
+    'Should be possible to replace notifySubscribers with a custom handler': function() {
+        var instance = new ko.subscribable();
+        var interceptedNotifications = [];
+        instance.subscribe(function() { throw new Error("Should not notify subscribers by default once notifySubscribers is overridden") });
+        instance.notifySubscribers = function(newValue, eventName) {
+            interceptedNotifications.push({ eventName: eventName, value: newValue });
+        };
+        instance.notifySubscribers(123, "myEvent");
+
+        value_of(interceptedNotifications.length).should_be(1);
+        value_of(interceptedNotifications[0].eventName).should_be("myEvent");
+        value_of(interceptedNotifications[0].value).should_be(123);
+    }    
 });
diff --git a/src/subscribables/dependentObservable.js b/src/subscribables/dependentObservable.js
@@ -71,13 +71,13 @@ ko.dependentObservable = function (evaluatorFunctionOrOptions, evaluatorFunction
             });
             var valueForThis = options["owner"] || evaluatorFunctionTarget; // If undefined, it will default to "window" by convention. This might change in the future.
             var newValue = options["read"].call(valueForThis);
-            dependentObservable.notifySubscribers(_latestValue, "beforeChange");
+            dependentObservable["notifySubscribers"](_latestValue, "beforeChange");
             _latestValue = newValue;
         } finally {
             ko.dependencyDetection.end();
         }
 
-        dependentObservable.notifySubscribers(_latestValue);
+        dependentObservable["notifySubscribers"](_latestValue);
         _hasBeenEvaluated = true;
     }
 

diff --git a/src/subscribables/observable.js b/src/subscribables/observable.js
@@ -22,8 +22,8 @@ ko.observable = function (initialValue) {
         }
     }
     ko.subscribable.call(observable);
-    observable.valueHasMutated = function () { observable.notifySubscribers(_latestValue); }
-    observable.valueWillMutate = function () { observable.notifySubscribers(_latestValue, "beforeChange"); }
+    observable.valueHasMutated = function () { observable["notifySubscribers"](_latestValue); }
+    observable.valueWillMutate = function () { observable["notifySubscribers"](_latestValue, "beforeChange"); }
     ko.utils.extend(observable, ko.observable['fn']);
 
     ko.exportProperty(observable, "valueHasMutated", observable.valueHasMutated);

diff --git a/src/subscribables/subscribable.js b/src/subscribables/subscribable.js
@@ -15,7 +15,6 @@ ko.subscribable = function () {
     ko.utils.extend(this, ko.subscribable['fn']);
     ko.exportProperty(this, 'subscribe', this.subscribe);
     ko.exportProperty(this, 'extend', this.extend);
-    ko.exportProperty(this, 'notifySubscribers', this.notifySubscribers);
     ko.exportProperty(this, 'getSubscriptionsCount', this.getSubscriptionsCount);
 }
 
@@ -36,7 +35,7 @@ ko.subscribable['fn'] = {
         return subscription;
     },
 
-    notifySubscribers: function (valueToNotify, event) {
+    "notifySubscribers": function (valueToNotify, event) {
         event = event || defaultEvent;
         if (this._subscriptions[event]) {
             ko.utils.arrayForEach(this._subscriptions[event].slice(0), function (subscription) {
@@ -62,7 +61,7 @@ ko.subscribable['fn'] = {
 
 
 ko.isSubscribable = function (instance) {
-    return typeof instance.subscribe == "function" && typeof instance.notifySubscribers == "function";
+    return typeof instance.subscribe == "function" && typeof instance["notifySubscribers"] == "function";
 };
 
 ko.exportSymbol('ko.subscribable', ko.subscribable);