class Gem::RequestSet::Lockfile

def relative_path_from(dest, base) # :nodoc:
  dest = File.expand_path(dest)
  base = File.expand_path(base)
  if dest.index(base) == 0
    offset = dest[base.size + 1..-1]
    return "." unless offset
    offset
  else
    dest
  end
end