Emit a "change" or "change:ATTRIBUTE_NAME" event when modifying attributes on an instance.

Author: benpickles

src/model_instance_methods.js

@@ -15,12 +15,14 @@ Model.InstanceMethods = {
       } else {
         this.changes[name] = value;
       }
+      this.trigger("change:" + name, [this])
       return this;
     } else if (typeof name === "object") {
       // Mass-assign attributes.
       for (var key in name) {
         this.attr(key, name[key]);
       }
+      this.trigger("change", [this])
       return this;
     } else {
       // Changes take precedent over attributes.

test/tests/model_rest_test.js

@@ -464,23 +464,16 @@ test("create event", 1, function() {
     this.persistence(Model.REST, "/posts")
   });
 
-  var events = []
-
-  // Stub trigger and capture its argument.
-  Post.prototype.trigger = function(name) {
-    events.push(name)
-  }
-
   var server = this.sandbox.useFakeServer()
   server.respondWith("POST", "/posts", [200, {
     "Content-Type": "application/json"
   }, JSON.stringify({ id: 1 })])
 
-  new Post().save()
+  var post = new Post()
+  post.bind("create", function() { ok(true) })
+  post.save()
 
   server.respond()
-
-  deepEqual(events, ["create"])
 });
 
 test("update event", 1, function() {

test/tests/model_test.js

@@ -277,3 +277,34 @@ test("saving a model with an id should add it to the collection if it isn't alre
 
   ok(Post.first() === post)
 })
+
+test("change event", 5, function() {
+  var Post = Model("post")
+  var post = new Post({ foo: "bar", abc: 123, xyz: 789 })
+
+  var events = []
+
+  post.bind("change", function(p) {
+    ok(p === post)
+    events.push("change")
+  })
+
+  post.bind("change:foo", function(p) {
+    ok(p === post)
+    events.push("change:foo")
+  })
+
+  post.bind("change:xyz", function(p) {
+    ok(p === post)
+    events.push("change:xyz")
+  })
+
+  post.bind("change:abc", function() {
+    ok(false)
+  })
+
+  post.attr("foo", "baz")
+  post.attr({ foo: "bob", xyz: 123 })
+
+  same(events, ["change:foo", "change:foo", "change:xyz", "change"])
+})