Add profile:strict rake task.

Rakefile

@@ -64,9 +64,9 @@ namespace :profile do
     ruby "./performance/profile.rb"
   end
 
-  desc "Run KCacheGrind"
+  desc "Run the liquid profile/performance coverage with strict parsing"
-  task :grind => :run  do
+  task :strict do
-    system "qcachegrind /tmp/liquid.rubyprof_calltreeprinter.txt"
+    ruby "./performance/profile.rb strict"
   end
 
 end

performance/profile.rb

@@ -1,6 +1,7 @@
 require 'stackprof' rescue fail("install stackprof extension/gem")
 require File.dirname(__FILE__) + '/theme_runner'
 
+Liquid::Template.error_mode = ARGV.first.to_sym if ARGV.first
 profiler = ThemeRunner.new
 profiler.run
 results = StackProf.run(mode: :cpu) do