$dispose in a component cannot update bindings

hsp/rt/cptwrapper.js

@@ -152,15 +152,17 @@ var CptWrapper = klass({
 
     $dispose : function () {
         // unobserve properties and events
+        var c=this.cpt;
+        if (c && c.$dispose) {
+            // call $dispose before removing the observer in case
+            // there is a last synchronization to do
+            c.$dispose();
+        }
         if (this._cptChgeCb) {
             json.unobserve(this.cpt, this._cptChgeCb);
             this._cptChgeCb = null;
         }
-        var c=this.cpt;
         if (c) {
-            if (c.$dispose) {
-                c.$dispose();
-            }
             c.nodeInstance = null;
             this.cpt = null;
         }
@@ -397,7 +399,7 @@ function createCptWrapper(Ctl, cptArgs) {
 
             if (attributes) {
                 for (var k in attributes) {
-                    
+
                     // set the template attribute value on the component instance
                     if (attributes.hasOwnProperty(k)) {
                         att=cw.cpt.attributes[k];

public/test/rt/cptintegration.spec.hsp

@@ -62,12 +62,58 @@ var TestCtrl1=klass({
 # /template
 
 
+var TextareaWithOnDisposeCtrl=klass({
+  attributes:{
+    text: {type:"string",binding:"2-way"}
+  },
+  $refresh: function() {
+    this.onTextChange();
+  },
+  onTextChange: function () {
+    var textarea = this.$getElement(0);
+    if (textarea) {
+      textarea.value = this.text;
+    }
+  },
+  $dispose: function() {
+    var textarea = this.$getElement(0);
+    if (textarea) {
+      this.text = textarea.value; 
+    }
+  }
+});
+
+# template textareaWithOnDispose using c:TextareaWithOnDisposeCtrl
+  <textarea></textarea>
+# /template
+
+# template useTextarea(data)
+  {if data.visible}
+    <#textareaWithOnDispose text="{data.text}" />
+  {/if}
+# /template
+
 describe("External component integration", function () {
     beforeEach(function() {
         msg='';
         refreshCount=0;
     });
 
+    it("validates $dispose is called before bindings are removed", function () {
+        var firstValue = "hello";
+        var h=ht.newTestContext(), d={visible: true, text:firstValue};
+        useTextarea(d).render(h.container);
+        var textarea = h("textarea");
+        expect(textarea.value()).to.equal(firstValue);
+        expect(d.text).to.equal(firstValue);
+        var secondValue = "new value";
+        textarea.type(secondValue);
+        expect(textarea.value()).to.equal(secondValue);
+        expect(d.text).to.equal(firstValue); // still the first value because the update in the data model is on dispose
+        h.$set(d,"visible", false);
+        expect(d.text).to.equal(secondValue); // data model update normally happens when disposing the textarea on the previous line
+    });
+
     it("validates $getElement() method through direct template call", function() {
         var h=ht.newTestContext(), d={value:"hello"};