module Cucumber::Messages::Varint

def self.decode_varint(io)
  # https://github.com/ruby-protobuf/protobuf/blob/master/lib/protobuf/varint_pure.rb
  value = index = 0
  begin
    byte = io.readbyte
    value |= (byte & 0x7f) << (7 * index)
    index += 1
  end while (byte & 0x80).nonzero?
  value
end

def self.encode_varint(io, int_val)
  if int_val < 0
    # negative varints are always encoded with the full 10 bytes
    int_val = int_val & 0xffffffff_ffffffff
  end
  loop do
    byte = int_val & 0x7f
    int_val >>= 7
    if int_val == 0
      io << byte.chr
      break
    else
      io << (byte | 0x80).chr
    end
  end
end