feat(SetObservation): add set observation

aurelia · Jan 6, 2016 · 9bb1731 · 9bb1731
1 parent e426534
commit 9bb1731
Show file tree

Hide file tree

Showing 5 changed files with 82 additions and 7 deletions.
diff --git a/build/tasks/build.js b/build/tasks/build.js
@@ -43,7 +43,8 @@ gulp.task('build-index', function(){
     'binding-behavior-resource.js',
     'listener-expression.js',
     'name-expression.js',
-    'binding-engine.js'
+    'binding-engine.js',
+    'set-observation.js'
     ].map(function(file){
       return paths.root + file;
   });

diff --git a/src/binding-engine.js b/src/binding-engine.js
@@ -66,8 +66,10 @@ export class BindingEngine {
           observer = this.observerLocator.getArrayObserver(collection);
         } else if (collection instanceof Map) {
           observer = this.observerLocator.getMapObserver(collection);
-        } else {
-          throw new Error('collection must be an instance of Array or Map.');
+        } else if (collection instanceof Set) {
+          observer = this.observerLocator.getSetObserver(collection);
+        }  else {
+          throw new Error('collection must be an instance of Array, Map or Set.');
         }
         observer.subscribe(callback);
         return {

diff --git a/src/collection-observation.js b/src/collection-observation.js
@@ -10,7 +10,7 @@ export class ModifyCollectionObserver {
     this.changeRecords = null;
     this.oldCollection = null;
     this.collection = collection;
-    this.lengthPropertyName = collection instanceof Map ? 'size' : 'length';
+    this.lengthPropertyName = collection instanceof Map || collection instanceof Set ? 'size' : 'length';
   }
 
   subscribe(context, callable) {
@@ -83,14 +83,14 @@ export class ModifyCollectionObserver {
     if (this.hasSubscribers()) {
       if (oldCollection){
         // TODO (martingust) we might want to refactor this to a common, independent of collection type, way of getting the records
-        if (this.collection instanceof Map) {
+        if (this.collection instanceof Map || this.collection instanceof Set) {
           records = getChangeRecords(oldCollection);
         } else {
           //we might need to combine this with existing change records....
           records = calcSplices(this.collection, 0, this.collection.length, oldCollection, 0, oldCollection.length);
         }
       } else {
-        if (this.collection instanceof Map) {
+        if (this.collection instanceof Map || this.collection instanceof Set) {
           records = changeRecords;
         } else {
           records = projectArraySplices(this.collection, changeRecords);
@@ -110,7 +110,7 @@ export class ModifyCollectionObserver {
 export class CollectionLengthObserver {
   constructor(collection) {
     this.collection = collection;
-    this.lengthPropertyName = collection instanceof Map ? 'size' : 'length';
+    this.lengthPropertyName = collection instanceof Map || collection instanceof Set ? 'size' : 'length';
     this.currentValue = collection[this.lengthPropertyName];
   }
 

diff --git a/src/observer-locator.js b/src/observer-locator.js
@@ -2,6 +2,7 @@ import {DOM} from 'aurelia-pal';
 import {TaskQueue} from 'aurelia-task-queue';
 import {getArrayObserver} from './array-observation';
 import {getMapObserver} from './map-observation';
+import {getSetObserver} from './set-observation';
 import {EventManager} from './event-manager';
 import {DirtyChecker, DirtyCheckProperty} from './dirty-checking';
 import {
@@ -160,6 +161,12 @@ export class ObserverLocator {
       } else {
         return new DirtyCheckProperty(this.dirtyChecker, obj, propertyName);
       }
+    } else if (obj instanceof Set) {
+      if (propertyName === 'size') {
+        return this.getSetObserver(obj).getLengthObserver();
+      } else {
+        return new DirtyCheckProperty(this.dirtyChecker, obj, propertyName);
+      }
     }
 
     return new SetterObserver(this.taskQueue, obj, propertyName);
@@ -197,6 +204,14 @@ export class ObserverLocator {
 
     return map.__map_observer__ = getMapObserver(this.taskQueue, map);
   }
+
+  getSetObserver(set){
+    if ('__set_observer__' in set) {
+      return set.__set_observer__;
+    }
+
+    return set.__set_observer__ = getSetObserver(this.taskQueue, set);
+  }
 }
 
 export class ObjectObservationAdapter {

diff --git a/src/set-observation.js b/src/set-observation.js
@@ -0,0 +1,57 @@
+import 'core-js';
+import {getChangeRecords} from './map-change-records';
+import {ModifyCollectionObserver} from './collection-observation';
+
+let setProto = Set.prototype;
+
+export function getSetObserver(taskQueue, set){
+  return ModifySetObserver.create(taskQueue, set);
+}
+
+class ModifySetObserver extends ModifyCollectionObserver {
+  constructor(taskQueue, set){
+    super(taskQueue, set);
+  }
+
+  static create(taskQueue, set) {
+    let observer = new ModifySetObserver(taskQueue, set);
+
+    set['add'] = function () {
+      let type = 'add';
+      let hasValue = set.has(arguments[0]);
+      let methodCallResult = setProto['add'].apply(set, arguments);
+      if (!hasValue) {
+        observer.addChangeRecord({
+          type: type,
+          object: set,
+          value: arguments[0]
+        });
+      }
+      return methodCallResult;
+    }
+
+    set['delete'] = function () {
+      let hasValue = set.has(arguments[0]);
+      let methodCallResult = setProto['delete'].apply(set, arguments);
+      if (hasValue) {
+        observer.addChangeRecord({
+          type: 'delete',
+          object: set,
+          value: arguments[0]
+        });
+      }
+      return methodCallResult;
+    }
+
+    set['clear'] = function () {
+      let methodCallResult = setProto['clear'].apply(set, arguments);
+      observer.addChangeRecord({
+        type: 'clear',
+        object: set
+      });
+      return methodCallResult;
+    }
+
+    return observer;
+  }
+}