avoid getting screwed when you update a gem you monkey-patch

when_monkeypatching

# If the behaviour the gem you're monkey patching changes
# your monkey patch might not work anymore
if Gem::Specification.all_names.detect { |gem_v| gem_v == 'haml-3.1.8' }
  # my monkey patch here
else
  raise "Please check this gem works with the above monkey patch"
end

👍