# Copyright (c) 2020 Contrast Security, Inc. See https://www.contrastsecurity.com/enduser-terms-0317a for more details.
# frozen_string_literal: true

module Contrast
  module Agent
    module Assess
      module Policy
        module Propagator
          # Propagation that results in all the tags of the source being
          # applied to the target exactly as is. The target's preexisting tags
          # are unaffected beyond any merging of overlapping tags.
          class Keep < Contrast::Agent::Assess::Policy::Propagator::Base
            class << self
              # Keep means the tags just pass from the source to the target
              # as is.
              def propagate propagation_node, preshift, target
                properties = Contrast::Agent::Assess::Tracker.properties(target)
                return unless properties

                source = find_source(propagation_node.sources[0], preshift)
                properties.copy_from(source, target, 0, propagation_node.untags)
              end
            end
          end
        end
      end
    end
  end
end