# File lib/dm-core/query/path.rb, line 68
      def initialize(relationships, property_name = nil)
        assert_kind_of 'relationships', relationships, Array
        assert_kind_of 'property_name', property_name, Symbol, NilClass

        @relationships = relationships.dup

        last_relationship = @relationships.last
        @repository_name  = last_relationship.relative_target_repository_name
        @model            = last_relationship.target_model

        if property_name
          @property = @model.properties(@repository_name)[property_name] ||
            raise(ArgumentError, "Unknown property '#{property_name}' in #{@model}")
        end
      end