unpack cookie benchmark

gistfile1.txt

require 'benchmark/ips'

def reverse(session_data)
  digest, session_data = session_data.reverse.split('--', 2)
  digest.reverse! if digest
  session_data.reverse! if session_data
  [session_data, digest]
end

def index(session_data)
  index = session_data.rindex('--')
  [session_data[0, index], session_data[index+2, session_data.length - (index+2)]]
end

def rpartition(session_data)
  session_data, _, digest = session_data.rpartition('--')
end

n = 10

data = 'a'*512 + '--' + 'b'*32

Benchmark.ips do |x|
  x.report('reverse:') { n.times { reverse(data) } }
  x.report('index:') { n.times { index(data) } }
  x.report('rpartition:') { n.times { rpartition(data) } }
end

results

            reverse:     64.886k (± 5.2%) i/s -    328.547k in   5.079341s
              index:    121.035k (± 1.8%) i/s -    607.898k in   5.024200s
         rpartition:    129.777k (± 3.0%) i/s -    651.896k in   5.027945s