def register_build(targets, command, deps, env)
      Array(targets).each do |target|
        target_checksum = Rscons.phony_target?(target) ? "" : calculate_checksum(target)
        @cache["targets"][get_cache_key(target)] = {
          "command" => Digest::MD5.hexdigest(command.inspect),
          "checksum" => target_checksum,
          "deps" => deps.map do |dep|
            {
              "fname" => dep,
              "checksum" => lookup_checksum(dep),
            }
          end,
          "user_deps" => (env.get_user_deps(target) || []).map do |dep|
            {
              "fname" => dep,
              "checksum" => lookup_checksum(dep),
            }
          end,
        }
      end
    end
def register_build(targets, command, deps, env)
      Array(targets).each do |target|
        target_checksum = Rscons.phony_target?(target) ? "" : calculate_checksum(target)
        @cache["targets"][get_cache_key(target)] = {
          "command" => Digest::MD5.hexdigest(command.inspect),
          "checksum" => target_checksum,
          "deps" => deps.map do |dep|
            {
              "fname" => dep,
              "checksum" => lookup_checksum(dep),
            }
          end,
          "user_deps" => (env.get_user_deps(target) || []).map do |dep|
            {
              "fname" => dep,
              "checksum" => lookup_checksum(dep),
            }
          end,
        }
      end
    end
Store cache information about target(s) built by a builder.

 @param targets [Symbol, String, Array<String>]
   The name of the target(s) built.
 @param command [String, Array, Hash]
   The command used to build the target. The command parameter can
   actually be a String, Array, or Hash and could contain information
   other than just the actual command used to build the target. For the
   purposes of the Cache, any difference in the command argument will
   trigger a rebuild.
 @param deps [Array<String>] List of dependencies for the target.
 @param env [Environment] The {Rscons::Environment}.

 @return [void]