Benchmarking tag vs content_tag vs string interpolation

benchmark_tag_vs_interpolation.rb

require 'benchmark'
require 'action_view'

include ActionView::Helpers::TagHelper
include ERB::Util

def output_buffer=(s)
end
def output_buffer
end

def test_tag(body, cls, style)
  tag(:div, class: cls, style: style) { body }
end

def test_content_tag(body, cls, style)
  content_tag(:div, body, class: cls, style: style) { body }
end

def test_interpolation(body, cls, style)
  "<div class='#{html_escape(cls)}' style='#{html_escape(style)}'>#{html_escape(body)}</div>".html_safe
end

def test_interpolation_cheat(body, cls, style)
  "<div class='#{cls}' style='#{style}'>#{body}</div>".html_safe
end

n = 100_000
Benchmark.bmbm(15) do |x|
  x.report("#tag")                     { n.times { test_tag("body", "foo", "color: white;") } }
  x.report("#content_tag")             { n.times { test_content_tag("body", "foo", "color: white;") } }
  x.report("interpolation")            { n.times { test_interpolation("body", "foo", "color: white;") } }
  x.report("interpolation (cheating)") { n.times { test_interpolation_cheat("body", "foo", "color: white;") } }
end

# >>                                user     system      total        real
# >> #tag                       0.357679   0.000528   0.358207 (  0.358630)
# >> #content_tag               0.648997   0.000605   0.649602 (  0.650111)
# >> interpolation              0.328803   0.000452   0.329255 (  0.329821)
# >> interpolation (cheating)   0.103121   0.000339   0.103460 (  0.103557)