github_dependency.cr

    def install
      unless Dir.exists?(target_dir)
        repo_url = if @use_ssh
          "git@github.com:#{@author}/#{@repository}.git"
        else
          "git://github.com/#{@author}/#{@repository}.git"
        end

        exec "git clone#{@branch} #{repo_url} #{target_dir}"
      end
      exec "ln -sf ../#{target_dir}/src libs/#{name}"

      if File.exists?("#{target_dir}/Projectfile")
        project = Crystal::Project.new
        project.eval do
          File.read_lines("#{target_dir}/Projectfile")
        end
        project.install_deps
      end

      if @locked_version
        if current_version != @locked_version
          exec "git -C #{target_dir} checkout -q #{@locked_version}"
        end
      else
        @locked_version = current_version
      end
    end