def comparator uuid
      prefix = objects[uuid][Keys::ISA] == Keys::PBXGroup ? '  ' : ''
      prefix + Helpers.resolve_attributes(uuid, objects)
    end
def comparator uuid
      prefix = objects[uuid][Keys::ISA] == Keys::PBXGroup ? '  ' : ''
      prefix + Helpers.resolve_attributes(uuid, objects)
    end
The comparator used during the sort

 The comparator resolves the attributes for the node and appends a
 known prefix to objects where `isa = PBXGroup` to ensure that groups
 are sorted above files

 @param uuid [String] the uuid of the object to examine
 @!visibility public