Yield the model to the sortBy callback.

Author: olly

src/collection.js

@@ -120,7 +120,7 @@
   Collection.prototype.sortBy = function(attribute_or_func) {
     var is_func = Model.Utils.isFunction(attribute_or_func)
     var extract = function(model) {
-      return attribute_or_func.call(model)
+      return attribute_or_func.call(model, model)
     }
 
     return this.sort(function(a, b) {

test/tests/collection_test.js

@@ -111,6 +111,24 @@ test("#sort, #sortBy", function() {
   ok(sorted.at(0) === a)
   ok(sorted.at(1) === b)
   ok(sorted.at(2) === c)
+
+  sorted = collection.sortBy(function() {
+    return this.get("title")
+  })
+
+  ok(sorted instanceof Model.Collection, "returns another Collection")
+  ok(sorted.at(0) === a)
+  ok(sorted.at(1) === b)
+  ok(sorted.at(2) === c)
+
+  sorted = collection.sortBy(function(post) {
+    return post.get("title")
+  })
+
+  ok(sorted instanceof Model.Collection, "returns another Collection")
+  ok(sorted.at(0) === a)
+  ok(sorted.at(1) === b)
+  ok(sorted.at(2) === c)
 })
 
 test("#detect", function() {