rails-views-ruby-or-plain-html.rb

require 'erb'
require 'benchmark'
require 'ostruct'
require 'action_view'
require 'rails'
include ActionView::Helpers::TagHelper
include ActionView::Helpers::TextHelper
include ActionView::Helpers::UrlHelper
data = OpenStruct.new name: 'Sample', email: 'sample@mail.com', list: %w(one two three)
@output = ''
def output_buffer=(string)
  @output = string
end
def output_buffer
  @output
end

erb_template = <<-ERB_TEMPLATE
<div>
  <%= content_tag :p, data.name %>
  <%= content_tag :p, data.email %>
  <ul>
  <% data.list.each do |l| %>
    <%= content_tag :li, l %>
  <% end %>
  <span><%= link_to "link", "path" %></span>
  </ul>
</div>
ERB_TEMPLATE
erb_template_concat = <<-ERB_TEMPLATE_CONCAT
<%= content_tag(:div) {
  concat content_tag(:p, data.name)
  concat content_tag(:p, data.email)
  concat content_tag(:ul) {
    data.list.each do |l|
      concat content_tag(:li, l)
    end
    concat(content_tag(:span) do
      link_to("link", "path")
    end)
  }
} %>
ERB_TEMPLATE_CONCAT

bind = binding
context = OpenStruct.new data: data
Benchmark.bmbm(10) do |b|
  b.report(:erb_new) { (1..10000).each { ERB.new(erb_template, 0, '', '@output').result bind } }
  b.report(:erb_concat) { (1..10000).each{ ERB.new(erb_template_concat, 0, '', '@output').result bind } }
end

$ ruby bm.rb 
Rehearsal ----------------------------------------------
erb_new      0.930000   0.050000   0.980000 (  1.087650)
erb_concat   1.100000   0.030000   1.130000 (  1.252630)
------------------------------------- total: 2.110000sec

                 user     system      total        real
erb_new      0.970000   0.010000   0.980000 (  1.077419)
erb_concat   1.120000   0.000000   1.120000 (  1.256709)

=> concat leads to a 15% drop in performance.

Hi @crohr !

Thanks for this Benchmark !

With RubyOnRails it is natively possible to define views with .ruby extension.
If you prefer .rb you add this to an initializer:

ActionView::Template.register_template_handler(:rb, :source.to_proc)

Then these views will be rendered without using ERB

views/path/my_veiw.html.ruby
views/path/my_veiw.html.rb

Could you make the same test without using ERB for .ruby/.rb views?