A benchmark for https://github.com/zenspider/enhanced-ruby-mode/pull/49

bm.rb

require 'benchmark'

def make_hash list
  Hash[list.map { |k| [k, true] }]
end

TRY_NUM = 1000000

{
 INDENT_KW: [:begin, :def, :case, :module, :class, :do, :for], # largest
 PRE_OPTIONAL_DO_KW: [:in, :while, :until] # smallest
}.each do |name, array|
  puts "-- #{name} --"
  hash = make_hash array

  Benchmark.bm do |x|
    x.report("array") {
      TRY_NUM.times do
        array.each {|i| array.include? i}
      end
    }
    x.report("hash")  {
      TRY_NUM.times do
        array.each {|i| hash.include? i}
      end
    }
  end
end

make_hash_bm.rb

require 'benchmark'

def make_hash list
  Hash[list.map { |k| [k, true] }]
end

TRY_NUM = 1000000

{
 INDENT_KW: [:begin, :def, :case, :module, :class, :do, :for],
 PRE_OPTIONAL_DO_KW: [:in, :while, :until]
}.each do |name, array|
  Benchmark.bm do |x|
    x.report(name)  {
      TRY_NUM.times do
        make_hash array
      end
    }
  end
end

bm.rb

-- INDENT_KW --
       user     system      total        real
array  4.210000   0.000000   4.210000 (  4.636992)
hash  2.440000   0.000000   2.440000 (  2.697857)
-- PRE_OPTIONAL_DO_KW --
       user     system      total        real
array  1.350000   0.010000   1.360000 (  1.498218)
hash  1.130000   0.000000   1.130000 (  1.248647)

make_hash_bm.rb

       user     system      total        real
INDENT_KW 11.450000   0.020000  11.470000 ( 12.964821)
       user     system      total        real
PRE_OPTIONAL_DO_KW  3.650000   0.010000   3.660000 (  4.102991)