mongo.rb in mongoid-4.0.0.alpha1

- old
+ new

@@ -10,29 +10,25 @@
         # @example Get all the aggregate values.
         #   aggregable.aggregates(:likes)
         #
         # @param [ String, Symbol ] field The field name.
         #
-        # @return [ Hash ] The aggregate values in the form:
+        # @return [ Hash ] count is a number of documents with the provided field. If there're none, then count is 0 and max, min, sum, avg are nil.
         #   {
         #     "count" => 2.0,
         #     "max" => 1000.0,
         #     "min" => 500.0,
         #     "sum" => 1500.0,
         #     "avg" => 750.0
         #   }
         #
         # @since 3.0.0
         def aggregates(field)
-          if query.count > 0
-            result = collection.aggregate(pipeline(field)).to_a
-            if result.empty?
-              { "count" => query.count, "avg" => 0, "sum" => 0 }
-            else
-              result.first
-            end
+          result = collection.aggregate(pipeline(field)).to_a
+          if result.empty?
+            { "count" => 0, "sum" => nil, "avg" => nil, "min" => nil, "max" => nil }
           else
-            { "count" => 0 }
+            result.first
           end
         end
 
         # Get the average value of the provided field.
         #