improved benchmark suite

performance/theme_runner.rb

@@ -0,0 +1,82 @@
+# This profiler run simulates Shopify.
+# We are looking in the tests directory for liquid files and render them within the designated layout file.
+# We will also export a substantial database to liquid which the templates can render values of. 
+# All this is to make the benchmark as non syntetic as possible. All templates and tests are lifted from
+# direct real-world usage and the profiler measures code that looks very similar to the way it looks in 
+# Shopify which is likely the biggest user of liquid in the world which something to the tune of several 
+# million Template#render calls a day. 
+
+require 'rubygems'
+require 'active_support'
+require 'yaml'
+require 'digest/md5'
+require File.dirname(__FILE__) + '/shopify/liquid'
+require File.dirname(__FILE__) + '/shopify/database.rb'
+
+class ThemeRunner
+
+  # Load all templates into memory, do this now so that 
+  # we don't profile IO. 
+  def initialize
+    @tests = Dir[File.dirname(__FILE__) + '/tests/**/*.liquid'].collect do |test|
+      next if File.basename(test) == 'theme.liquid'
+
+      theme_path = File.dirname(test) + '/theme.liquid'
+
+      [File.read(test), (File.file?(theme_path) ? File.read(theme_path) : nil), test]
+    end.compact
+  end  
+
+
+  def run(profile = false)
+    RubyProf.measure_mode = RubyProf::WALL_TIME if profile
+
+    # Dup assigns because will make some changes to them
+    assigns = Database.tables.dup
+
+    @tests.each do |liquid, layout, template_name|
+
+      # Compute page_tempalte outside of profiler run, uninteresting to profiler
+      html = nil
+      page_template = File.basename(template_name, File.extname(template_name))
+
+      # Profile compiling and rendering both
+      
+      if profile
+
+        RubyProf.resume do 
+          html = compile_and_render(liquid, layout, assigns, page_template) 
+        end 
+
+      else
+        html = compile_and_render(liquid, layout, assigns, page_template) 
+      end
+
+      # return the result and the MD5 of the content, this can be used to detect regressions between liquid version
+      $stdout.puts "* rendered template %s, content: %s" % [template_name, Digest::MD5.hexdigest(html)] if profile
+ 
+      # Uncomment to dump html files to /tmp so that you can inspect for errors
+      # File.open("/tmp/#{File.basename(template_name)}.html", "w+") { |fp| fp <<html}
+    end
+
+    RubyProf.stop if profile
+  end
+
+  def compile_and_render(template, layout, assigns, page_template)    
+    tmpl = Liquid::Template.new
+    tmpl.assigns['page_title'] = 'Page title'
+    tmpl.assigns['template'] = page_template
+
+    content_for_layout = tmpl.parse(template).render(assigns)
+
+    if layout
+      assigns['content_for_layout'] = content_for_layout      
+      tmpl.parse(layout).render(assigns)
+    else
+      content_for_layout
+    end    
+  end
+end
+
+
+