[FEATURE ember-router-willtransition]

FEATURES.md

@@ -204,3 +204,18 @@ for a detailed explanation.
   ```
 
   Added in [#10160](https://github.com/emberjs/ember.js/pull/10160)
+
+* `ember-router-willtransition`
+
+
+  Adds `willTransition` hook to `Ember.Router`. For example:
+
+  ```js
+  Ember.Router.extend({
+    onBeforeTransition: function(transition) {
+      //doSomething
+    }.on('willTransition')
+  });
+  ```
+
+  Added in [#10274](https://github.com/emberjs/ember.js/pull/10274)

bower.json

@@ -8,7 +8,7 @@
   "devDependencies": {
     "backburner": "https://github.com/ebryn/backburner.js.git#f4bd6a2df221240ed36d140f0c53c036a7ecacad",
     "rsvp": "https://github.com/tildeio/rsvp.js.git#3.0.14",
-    "router.js": "https://github.com/tildeio/router.js.git#a1ffd97dc66a6d9d4e8dd89a72c1c4e21a3328c5",
+    "router.js": "https://github.com/tildeio/router.js.git#72eb0d336c1c3b7ad3965198b330fe148d935efe",
     "dag-map": "https://github.com/krisselden/dag-map.git#e307363256fe918f426e5a646cb5f5062d3245be",
     "ember-dev": "https://github.com/emberjs/ember-dev.git#1c30a1666273ab2a9b134a42bad28c774f9ecdfc"
   }

features.json

@@ -16,7 +16,8 @@
     "ember-metal-stream": null,
     "ember-htmlbars-each-with-index": true,
     "ember-application-instance-initializers": null,
-    "ember-application-initializer-context": null
+    "ember-application-initializer-context": null,
+    "ember-router-willtransition": true
   },
   "debugStatements": [
     "Ember.warn",

packages/ember-htmlbars/lib/helpers/view.js

@@ -4,6 +4,7 @@
 */
 
 import Ember from "ember-metal/core"; // Ember.warn, Ember.assert
+import { read } from "ember-metal/streams/utils";
 import { readViewFactory } from "ember-views/streams/utils";
 import View from "ember-views/views/view";
 import mergeViewBindings from "ember-htmlbars/system/merge-view-bindings";
@@ -190,7 +191,7 @@ export function viewHelper(params, hash, options, env) {
     params.length <= 2
   );
 
-  var container = this.container || this._keywords.view.value().container;
+  var container = this.container || read(this._keywords.view).container;
   var viewClassOrInstance;
   if (params.length === 0) {
     if (container) {

packages/ember-routing/lib/system/router.js

@@ -188,6 +188,24 @@ var EmberRouter = EmberObject.extend(Evented, {
     }
   },
 
+  /**
+    Handles notifying any listeners of an impending URL
+    change.
+
+    Triggers the router level `willTransition` hook.
+
+    @method willTransition
+    @private
+    @since 1.11.0
+  */
+  willTransition: function(oldInfos, newInfos, transition) {
+    run.once(this, this.trigger, 'willTransition', transition);
+
+    if (get(this, 'namespace').LOG_TRANSITIONS) {
+      Ember.Logger.log("Preparing to transition from '" + EmberRouter._routePath(oldInfos) + "' to '" + EmberRouter._routePath(newInfos) + "'");
+    }
+  },
+
   handleURL: function(url) {
     // Until we have an ember-idiomatic way of accessing #hashes, we need to
     // remove it because router.js doesn't know how to handle it.
@@ -419,6 +437,12 @@ var EmberRouter = EmberObject.extend(Evented, {
     router.didTransition = function(infos) {
       emberRouter.didTransition(infos);
     };
+
+    if (Ember.FEATURES.isEnabled('ember-router-willtransition')) {
+      router.willTransition = function(oldInfos, newInfos, transition) {
+        emberRouter.willTransition(oldInfos, newInfos, transition);
+      };
+    }
   },
 
   _serializeQueryParams: function(targetRouteName, queryParams) {

packages/ember-views/lib/views/component.js

@@ -113,6 +113,7 @@ var Component = View.extend(TargetActionSupport, ComponentTemplateDeprecation, {
 
   init: function() {
     this._super();
+    this._keywords.view = this;
     set(this, 'context', this);
     set(this, 'controller', this);
   },
@@ -158,9 +159,7 @@ var Component = View.extend(TargetActionSupport, ComponentTemplateDeprecation, {
   */
   templateName: null,
 
-  _setupKeywords: function() {
-    this._keywords.view.setSource(this);
-  },
+  _setupKeywords: function() {},
 
   _yield: function(context, options, morph, blockArguments) {
     var view = options.data.view;

packages/ember-views/lib/views/view.js

@@ -24,7 +24,6 @@ import {
   observer,
   beforeObserver
 } from "ember-metal/mixin";
-import SimpleStream from "ember-metal/streams/simple";
 import KeyStream from "ember-views/streams/key_stream";
 import StreamBinding from "ember-metal/streams/stream_binding";
 import ContextStream from "ember-views/streams/context_stream";
@@ -1070,7 +1069,7 @@ var View = CoreView.extend({
     if (contextView) {
       var parentKeywords = contextView._keywords;
 
-      keywords.view.setSource(this.isVirtual ? parentKeywords.view : this);
+      keywords.view = this.isVirtual ? parentKeywords.view : this;
 
       for (var name in parentKeywords) {
         if (keywords[name]) {
@@ -1080,7 +1079,7 @@ var View = CoreView.extend({
         keywords[name] = parentKeywords[name];
       }
     } else {
-      keywords.view.setSource(this.isVirtual ? null : this);
+      keywords.view = this.isVirtual ? null : this;
     }
   },
 
@@ -1753,8 +1752,8 @@ var View = CoreView.extend({
     if (!this._keywords) {
       this._keywords = create(null);
     }
-    this._keywords.view = new SimpleStream();
     this._keywords._view = this;
+    this._keywords.view = undefined;
     this._keywords.controller = new KeyStream(this, 'controller');
     this._setupKeywords();
 

packages/ember-views/tests/views/container_view_test.js

@@ -2,6 +2,7 @@ import { get } from "ember-metal/property_get";
 import { set } from "ember-metal/property_set";
 import run from "ember-metal/run_loop";
 import { computed } from "ember-metal/computed";
+import { read } from "ember-metal/streams/utils";
 import Controller from "ember-runtime/controllers/controller";
 import jQuery from "ember-views/system/jquery";
 import View from "ember-views/views/view";
@@ -300,8 +301,8 @@ test("if a ContainerView starts with a currentView, it is rendered as a child vi
   equal(container.objectAt(0), mainView, "should have the currentView as the only child view");
   equal(mainView.get('parentView'), container, "parentView is setup");
   equal(context, container.get('context'), 'context preserved');
-  equal(mainView._keywords.controller.value(), controller, 'controller keyword is setup');
-  equal(mainView._keywords.view.value(), mainView, 'view keyword is setup');
+  equal(read(mainView._keywords.controller), controller, 'controller keyword is setup');
+  equal(read(mainView._keywords.view), mainView, 'view keyword is setup');
 });
 
 test("if a ContainerView is created with a currentView, it is rendered as a child view", function() {
@@ -329,8 +330,8 @@ test("if a ContainerView is created with a currentView, it is rendered as a chil
   equal(container.objectAt(0), mainView, "should have the currentView as the only child view");
   equal(mainView.get('parentView'), container, "parentView is setup");
   equal(context, container.get('context'), 'context preserved');
-  equal(mainView._keywords.controller.value(), controller, 'controller keyword is setup');
-  equal(mainView._keywords.view.value(), mainView, 'view keyword is setup');
+  equal(read(mainView._keywords.controller), controller, 'controller keyword is setup');
+  equal(read(mainView._keywords.view), mainView, 'view keyword is setup');
 });
 
 test("if a ContainerView starts with no currentView and then one is set, the ContainerView is updated", function() {
@@ -364,8 +365,8 @@ test("if a ContainerView starts with no currentView and then one is set, the Con
   equal(container.objectAt(0), mainView, "should have the currentView as the only child view");
   equal(mainView.get('parentView'), container, "parentView is setup");
   equal(context, container.get('context'), 'context preserved');
-  equal(mainView._keywords.controller.value(), controller, 'controller keyword is setup');
-  equal(mainView._keywords.view.value(), mainView, 'view keyword is setup');
+  equal(read(mainView._keywords.controller), controller, 'controller keyword is setup');
+  equal(read(mainView._keywords.view), mainView, 'view keyword is setup');
 });
 
 test("if a ContainerView starts with a currentView and then is set to null, the ContainerView is updated", function() {
@@ -394,8 +395,8 @@ test("if a ContainerView starts with a currentView and then is set to null, the
   equal(container.objectAt(0), mainView, "should have the currentView as the only child view");
   equal(mainView.get('parentView'), container, "parentView is setup");
   equal(context, container.get('context'), 'context preserved');
-  equal(mainView._keywords.controller.value(), controller, 'controller keyword is setup');
-  equal(mainView._keywords.view.value(), mainView, 'view keyword is setup');
+  equal(read(mainView._keywords.controller), controller, 'controller keyword is setup');
+  equal(read(mainView._keywords.view), mainView, 'view keyword is setup');
 
   run(function() {
     set(container, 'currentView', null);
@@ -431,8 +432,8 @@ test("if a ContainerView starts with a currentView and then is set to null, the
   equal(container.objectAt(0), mainView, "should have the currentView as the only child view");
   equal(mainView.get('parentView'), container, "parentView is setup");
   equal(context, container.get('context'), 'context preserved');
-  equal(mainView._keywords.controller.value(), controller, 'controller keyword is setup');
-  equal(mainView._keywords.view.value(), mainView, 'view keyword is setup');
+  equal(read(mainView._keywords.controller), controller, 'controller keyword is setup');
+  equal(read(mainView._keywords.view), mainView, 'view keyword is setup');
 
   run(function() {
     set(container, 'currentView', null);

packages/ember/tests/routing/basic_test.js

@@ -2738,6 +2738,54 @@ test("Route silently fails when cleaning an outlet from an inactive view", funct
   Ember.run(function() { router.send('hideModal'); });
 });
 
+if (Ember.FEATURES.isEnabled('ember-router-willtransition')) {
+  test("Router `willTransition` hook passes in cancellable transition", function() {
+    // Should hit willTransition 3 times, once for the initial route, and then 2 more times
+    // for the two handleURL calls below
+    expect(3);
+
+    Router.map(function() {
+      this.route("nork");
+      this.route("about");
+    });
+
+    Router.reopen({
+      init: function() {
+        this._super();
+        this.on('willTransition', this.testWillTransitionHook);
+      },
+      testWillTransitionHook: function(transition, url) {
+        ok(true, "willTransition was called " + url);
+        transition.abort();
+      }
+    });
+
+    App.LoadingRoute = Ember.Route.extend({
+      activate: function() {
+        ok(false, "LoadingRoute was not entered");
+      }
+    });
+
+    App.NorkRoute = Ember.Route.extend({
+      activate: function() {
+        ok(false, "NorkRoute was not entered");
+      }
+    });
+
+    App.AboutRoute = Ember.Route.extend({
+      activate: function() {
+        ok(false, "AboutRoute was not entered");
+      }
+    });
+
+    bootApplication();
+
+    // Attempted transitions out of index should abort.
+    Ember.run(router, 'handleURL', '/nork');
+    Ember.run(router, 'handleURL', '/about');
+  });
+}
+
 test("Aborting/redirecting the transition in `willTransition` prevents LoadingRoute from being entered", function() {
   expect(8);