Merge branch 'feature/changed-method'

docs/reference/collection-events.md

@@ -96,6 +96,28 @@ Prevents a property from being updated.
     // Example: On Put
     // Protect a property
     protect('createdDate');
+    
+
+### changed()
+
+    changed(property)
+
+Returns whether a property has been updated.
+
+    // Example: On Put
+    // Validate the title when it changes
+    if(changed('title') && this.title.length < 5) {
+      error('title', 'must be over 5 characters');
+    }
+    
+### previous
+
+An `Object` containing the previous values of the item to be updated.
+
+    // Example: On Put
+    if(this.votes < previous.votes) {
+      emit('votes have decreased');
+    }
 
 ### emit()
 

lib/resources/collection/index.js

@@ -470,13 +470,20 @@ Collection.prototype.save = function (ctx, fn) {
     protect: function(property) {
       delete item[property];
     },
+    changed: function (property) {
+      if(item.hasOwnProperty(property)) return true;
+      return false;
+    },
     'this': item,
-    data: item
+    data: item,
+    previous: {}
   };
 
   function put() {
     var id = query.id
-      , sanitizedQuery = collection.sanitizeQuery(query);
+      , sanitizedQuery = collection.sanitizeQuery(query)
+      , prev = {};
+      
     store.first(sanitizedQuery, function(err, obj) {
       if(!obj) {
         if (Object.keys(sanitizedQuery) === 1) {
@@ -489,12 +496,14 @@ Collection.prototype.save = function (ctx, fn) {
 
       // merge changes
       Object.keys(item).forEach(function (key) {
+        prev[key] = obj[key];
         obj[key] = item[key];
       });
 
       item = obj;
       domain['this'] = item;
       domain.data = item;
+      domain.previous = prev;
 
       collection.execCommands('update', item, commands);
 

lib/script.js

@@ -13,7 +13,6 @@ function Script(src, path) {
   } catch(ex) {
     this.error = ex;
   }
-  
 }
 
 /**
@@ -147,6 +146,7 @@ function wrapAsyncFunctions(asyncFunctions, sandbox, events, done, sandboxRoot)
         var args = _.toArray(arguments);
         var callback;
         var callbackIndex;
+        var result;
         
         for(var i = 0; i < args.length; i++) {
           if(typeof args[i] == 'function') {
@@ -161,7 +161,7 @@ function wrapAsyncFunctions(asyncFunctions, sandbox, events, done, sandboxRoot)
           args[callbackIndex] = function() {
             if (sandboxRoot._error) return;
             try {
-              callback.apply(sandboxRoot._this, arguments);
+              result = callback.apply(sandboxRoot._this, arguments);
               events.emit('finishCallback');
             } catch (err) {
               var wrappedErr = wrapError(err);
@@ -176,12 +176,16 @@ function wrapAsyncFunctions(asyncFunctions, sandbox, events, done, sandboxRoot)
           });
         }
         try {
-          asyncFunctions[k].apply(sandboxRoot._this, args);
+          result = asyncFunctions[k].apply(sandboxRoot._this, args);
         } catch(err) {
           var wrappedErr = wrapError(err);
           sandbox._error = wrappedErr;
           return done(wrappedErr);
         }
+        
+        if(result !== undefined) {
+          return result;
+        }
       };
     } else if (typeof asyncFunctions[k] === 'object') {
       sandbox[k] = sandbox[k] || {};

test-app/public/test/collection.test.js

@@ -794,5 +794,23 @@ describe('Collection', function() {
     });
   });
 
+  describe('changed()', function(){
+    it('should detect when a value has changed', function(done) {
+      dpd.changed.post({name: 'original'}, function (c) {
+        dpd.changed.put(c.id, {name: 'first name change'}, function (c) {
+          if(c.name !== 'saw first name changed previous original') {
+            throw Error('missed name change');
+          }
+          done();
+        });
+      });
+    });
+    
+    afterEach(function (done) {
+      this.timeout(10000);
+      cleanCollection(dpd.changed, done);
+    });
+  });
+
   
 });

test-app/resources/changed/config.json

@@ -0,0 +1,13 @@
+{
+	"type": "Collection",
+	"properties": {
+		"name": {
+			"name": "name",
+			"type": "string",
+			"typeLabel": "string",
+			"required": false,
+			"id": "name",
+			"order": 0
+		}
+	}
+}

test-app/resources/changed/post.js

@@ -0,0 +1,3 @@
+if(!(changed('name') && previous.name === undefined)) {
+    cancel('changed and/or previous are broken...');
+}

test-app/resources/changed/validate.js

@@ -0,0 +1,5 @@
+if(this.name === 'first name change') {
+    if(changed('name')) {
+        this.name = 'saw first name changed previous ' + previous.name;
+    }
+}