brew/Library/Homebrew/cask/lib/hbc/artifact/symlinked.rb

require "hbc/artifact/relocated"

module Hbc
  module Artifact
    class Symlinked < Relocated
      def self.link_type_english_name
        "Symlink"
      end

      def self.english_description
        "#{artifact_english_name} #{link_type_english_name}s"
      end

      def self.islink?(path)
        path.symlink?
      end

      def link(artifact_spec)
        load_specification artifact_spec
        return unless preflight_checks(source, target)
        ohai "#{self.class.link_type_english_name}ing #{self.class.artifact_english_name} '#{source.basename}' to '#{target}'"
        create_filesystem_link(source, target)
      end

      def unlink(artifact_spec)
        load_specification artifact_spec
        return unless self.class.islink?(target)
        ohai "Removing #{self.class.artifact_english_name} #{self.class.link_type_english_name.downcase}: '#{target}'"
        target.delete
      end

      def install_phase
        @cask.artifacts[self.class.artifact_dsl_key].each(&method(:link))
      end

      def uninstall_phase
        @cask.artifacts[self.class.artifact_dsl_key].each(&method(:unlink))
      end

      def preflight_checks(source, target)
        if target.exist? && !self.class.islink?(target)
          ohai "It seems there is already #{self.class.artifact_english_article} #{self.class.artifact_english_name} at '#{target}'; not linking."
          return false
        end
        unless source.exist?
          raise CaskError, "It seems the #{self.class.link_type_english_name.downcase} source is not there: '#{source}'"
        end
        true
      end

      def create_filesystem_link(source, target)
        Pathname.new(target).dirname.mkpath
        @command.run!("/bin/ln", args: ["-hfs", "--", source, target])
        add_altname_metadata source, target.basename.to_s
      end

      def summarize_artifact(artifact_spec)
        load_specification artifact_spec

        if self.class.islink?(target) && target.exist? && target.readlink.exist?
          "#{printable_target} -> #{target.readlink} (#{target.readlink.abv})"
        else
          string = if self.class.islink?(target)
                     "#{printable_target} -> #{target.readlink}"
                   else
                     printable_target
                   end

          Formatter.error(string, label: "Broken Link")
        end
      end
    end
  end
end