From 7cdeefc69bd1d62e068a5052c99ad0da2c8d91f6 Mon Sep 17 00:00:00 2001
From: Edward Faulkner <ef@alum.mit.edu>
Date: Tue, 21 Oct 2014 15:11:52 -0400
Subject: [PATCH] Make computed.sort generate an answer immediately

This is a followup to pull #9356 that gives nicer timing. It extends the
arrayComputed protocol with a `flushedChanges` callback so that
implementations like `computed.sort` can confidently do batched
operations without waiting a whole run loop.
---
 packages/ember-runtime/lib/computed/reduce_computed.js    | 8 ++++++--
 .../ember-runtime/lib/computed/reduce_computed_macros.js  | 5 ++++-
 .../tests/computed/reduce_computed_macros_test.js         | 5 +++--
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/packages/ember-runtime/lib/computed/reduce_computed.js b/packages/ember-runtime/lib/computed/reduce_computed.js
index 62a4a1df944..8e2468949b2 100644
--- a/packages/ember-runtime/lib/computed/reduce_computed.js
+++ b/packages/ember-runtime/lib/computed/reduce_computed.js
@@ -277,6 +277,7 @@ DependentArraysObserver.prototype = {
       this.setValue(removedItem.call(
         this.instanceMeta.context, this.getValue(), item, changeMeta, this.instanceMeta.sugarMeta));
     }
+    this.callbacks.flushedChanges.call(this.instanceMeta.context, this.getValue(), this.instanceMeta.sugarMeta);
   },
 
   dependentArrayDidChange: function (dependentArray, index, removedCount, addedCount) {
@@ -308,7 +309,7 @@ DependentArraysObserver.prototype = {
       this.setValue(addedItem.call(
         this.instanceMeta.context, this.getValue(), item, changeMeta, this.instanceMeta.sugarMeta));
     }, this);
-
+    this.callbacks.flushedChanges.call(this.instanceMeta.context, this.getValue(), this.instanceMeta.sugarMeta);
     this.trackAdd(dependentKey, normalizedIndex, observerContexts);
   },
 
@@ -352,6 +353,7 @@ DependentArraysObserver.prototype = {
     }
 
     this.changedItems = {};
+    this.callbacks.flushedChanges.call(this.instanceMeta.context, this.getValue(), this.instanceMeta.sugarMeta);
   }
 };
 
@@ -388,6 +390,7 @@ function addItems(dependentArray, callbacks, cp, propertyName, meta) {
     meta.setValue( callbacks.addedItem.call(
       this, meta.getValue(), item, new ChangeMeta(dependentArray, item, index, propertyName, cp, dependentArray.length), meta.sugarMeta));
   }, this);
+  callbacks.flushedChanges.call(this, meta.getValue(), meta.sugarMeta);
 }
 
 function reset(cp, propertyName) {
@@ -562,7 +565,8 @@ ReduceComputedProperty.prototype._callbacks = function () {
 
     this.callbacks = {
       removedItem: options.removedItem || defaultCallback,
-      addedItem: options.addedItem || defaultCallback
+      addedItem: options.addedItem || defaultCallback,
+      flushedChanges: options.flushedChanges || defaultCallback
     };
   }
 
diff --git a/packages/ember-runtime/lib/computed/reduce_computed_macros.js b/packages/ember-runtime/lib/computed/reduce_computed_macros.js
index 979a3e2fa88..7bea20e6e5d 100644
--- a/packages/ember-runtime/lib/computed/reduce_computed_macros.js
+++ b/packages/ember-runtime/lib/computed/reduce_computed_macros.js
@@ -715,7 +715,6 @@ function customSort(itemsKey, comparator) {
       };
       instanceMeta.insertLater = function(item) {
         this.waitingInsertions.push(item);
-        run.once(this, 'insertWaiting');
       };
     },
 
@@ -727,6 +726,10 @@ function customSort(itemsKey, comparator) {
     removedItem: function (array, item, changeMeta, instanceMeta) {
       array.removeObject(item);
       return array;
+    },
+
+    flushedChanges: function(array, instanceMeta) {
+      instanceMeta.insertWaiting();
     }
   });
 }
diff --git a/packages/ember-runtime/tests/computed/reduce_computed_macros_test.js b/packages/ember-runtime/tests/computed/reduce_computed_macros_test.js
index 6addf78fae1..13d575b0820 100644
--- a/packages/ember-runtime/tests/computed/reduce_computed_macros_test.js
+++ b/packages/ember-runtime/tests/computed/reduce_computed_macros_test.js
@@ -1191,16 +1191,17 @@ test("sorts correctly with a user-provided comparator when there are concurrent
   var sorted;
   run(function() {
     sorted = obj.get('customSortedItems');
+    deepEqual(sorted.mapBy('name'), ['A', 'B', 'C', 'D'], "initial");
   });
-  deepEqual(sorted.mapBy('name'), ['A', 'B', 'C', 'D'], "initial");
+
   run(function() {
     Ember.changeProperties(function(){
       obj.get('items').objectAt(1).set('count', 5);
       obj.get('items').objectAt(2).set('count', 6);
     });
     sorted = obj.get('customSortedItems');
+    deepEqual(sorted.mapBy('name'), ['A', 'D', 'B', 'C'], "final");
   });
-  deepEqual(sorted.mapBy('name'), ['A', 'D', 'B', 'C'], "final");
 });