class HTTPClient::OAuth

def self.escape(str) # :nodoc:
  if str.respond_to?(:force_encoding)
    str.dup.force_encoding('BINARY').gsub(/([^a-zA-Z0-9_.~-]+)/) {
      '%' + $1.unpack('H2' * $1.bytesize).join('%').upcase
    }
  else
    str.gsub(/([^a-zA-Z0-9_.~-]+)/n) {
      '%' + $1.unpack('H2' * $1.bytesize).join('%').upcase
    }
  end
end