class Sprockets::Manifest

def initialize(environment, path)


Manifest.new(environment, "./public/assets/manifest.json")

filename will default to "manifest.json" in that directory.
compiled assets to. Otherwise, if the path is a directory, the
already exist. The dirname of the `path` will be used to write
a full path to the manifest json file. The file may or may not
Create new Manifest associated with an `environment`. `path` is 
def initialize(environment, path)
  @environment = environment
  if File.extname(path) == ""
    @dir  = File.expand_path(path)
    @path = File.join(@dir, 'manifest.json')
  else
    @path = File.expand_path(path)
    @dir  = File.dirname(path)
  end
  data = nil
  begin
    if File.exist?(@path)
      data = json_decode(File.read(@path))
    end
  rescue MultiJson::DecodeError => e
    logger.error "#{@path} is invalid: #{e.class} #{e.message}"
  end
  @data = data.is_a?(Hash) ? data : {}
end