class Bundler::Dsl

def eval_gemfile(gemfile, contents = nil)
  contents ||= Bundler.read_file(gemfile.to_s)
  instance_eval(contents, gemfile.to_s, 1)
rescue Exception => e
  message = "There was an error " \
    "#{e.is_a?(GemfileEvalError) ? "evaluating" : "parsing"} " \
    "`#{File.basename gemfile.to_s}`: #{e.message}"
  raise DSLError.new(message, gemfile, e.backtrace, contents)
end