string_concat_test.rb

output

Warming up --------------------------------------
       interpolation   151.958k i/100ms
         StringIO <<    57.897k i/100ms
     StringIO concat   103.750k i/100ms
Calculating -------------------------------------
       interpolation      2.482M (± 9.9%) i/s -      9.877M in   4.027092s
         StringIO <<     45.806B (±33.8%) i/s -    119.834B
     StringIO concat    100.679B (±15.4%) i/s -    272.862B

Comparison:
     StringIO concat: 100679464490.0 i/s
         StringIO <<: 45806087656.3 i/s - 2.20x  slower
       interpolation:  2482226.0 i/s - 40560.15x  slower

(base) [13:58:40] ~/github/fishbrain/rutilus-api
[assume-catches-migrated !?] > ruby ips_test.rb
Warming up --------------------------------------
       interpolation   170.913k i/100ms
         StringIO <<    58.093k i/100ms
           String <<   119.074k i/100ms
       String concat    98.595k i/100ms
Calculating -------------------------------------
       interpolation      2.551M (± 6.7%) i/s -     10.255M in   4.040887s
         StringIO <<     45.450B (±34.4%) i/s -    118.516B
           String <<    115.444B (±15.8%) i/s -    302.462B
       String concat     95.624B (±15.6%) i/s -    259.181B

Comparison:
           String <<: 115443957094.8 i/s
       String concat: 95623886021.4 i/s - same-ish: difference falls within error
         StringIO <<: 45450279262.0 i/s - 2.54x  slower
       interpolation:  2550683.1 i/s - 45260.02x  slower

string_concat_test.rb

require 'benchmark/ips'

s1 = "fooo"
s2 = "baaar"
s3 = "baaazzz"

Benchmark.ips do |x|
  x.config(:time => 4, :warmup => 1)

  x.report("interpolation") do
    "heya#{s1}hiya#{s2}hoya#{s3}huya"
  end

  x.report("StringIO <<") do |times|
    StringIO.new.tap do |out|
      out << 'heya'
      out << s1
      out << 'hiya'
      out << s2
      out << 'hoya'
      out << s3
      out << 'huya'
    end.string
  end

  x.report("String <<") do |times|
    ''.tap do |out|
      out << 'heya'
      out << s1
      out << 'hiya'
      out << s2
      out << 'hoya'
      out << s3
      out << 'huya'
    end
  end

  x.report("String concat") do |times|
    "".tap do |out|
      out.concat('heya')
      out.concat(s1)
      out.concat('hiya')
      out.concat(s2)
      out.concat('hoya')
      out.concat(s3)
      out.concat('huya')
    end
  end

  # Compare the iterations per second of the various reports!
  x.compare!
end