simple refactoring

app/models/group.rb

@@ -1,15 +1,3 @@
-# == Schema Information
-#
-# Table name: groups
-#
-#  id         :integer         not null, primary key
-#  name       :string(255)     not null
-#  code       :string(255)     not null
-#  owner_id   :integer         not null
-#  created_at :datetime        not null
-#  updated_at :datetime        not null
-#
-
 class Group < ActiveRecord::Base
   attr_accessible :code, :name, :owner_id
 
@@ -18,7 +6,7 @@ class Group < ActiveRecord::Base
 
   validates :name, presence: true, uniqueness: true
   validates :code, presence: true, uniqueness: true
-  validates :owner_id, presence: true
+  validates :owner, presence: true
 
   delegate :name, to: :owner, allow_nil: true, prefix: true
 
@@ -31,6 +19,18 @@ class Group < ActiveRecord::Base
   end
 
   def users
-    User.joins(:users_projects).where('users_projects.project_id' => project_ids).uniq
+    User.joins(:users_projects).where(users_projects: {project_id: project_ids}).uniq
   end
 end
+
+# == Schema Information
+#
+# Table name: groups
+#
+#  id         :integer         not null, primary key
+#  name       :string(255)     not null
+#  code       :string(255)     not null
+#  owner_id   :integer         not null
+#  created_at :datetime        not null
+#  updated_at :datetime        not null
+#