NoMethodError: undefined method `upper' for nil:NilClass

gistfile1.txt

>> nil.freeze
=> nil
>> Tilt.new("/Users/warner/work/newco/app/views/cancellation_policies/1_one_night.html.haml").render(nil, :opts => {})
NoMethodError: undefined method `upper' for nil:NilClass
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/activesupport-3.1.3/lib/active_support/whiny_nil.rb:48:in `method_missing'
	from /Users/warner/work/newco/app/views/cancellation_policies/1_one_night.html.haml:18:in `ensure in evaluate_source'
	from /Users/warner/work/newco/app/views/cancellation_policies/1_one_night.html.haml:18:in `evaluate_source'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/tilt-1.3.3/lib/tilt/template.rb:209:in `instance_eval'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/tilt-1.3.3/lib/tilt/template.rb:209:in `evaluate_source'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/tilt-1.3.3/lib/tilt/template.rb:144:in `cached_evaluate'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/tilt-1.3.3/lib/tilt/template.rb:127:in `evaluate'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/tilt-1.3.3/lib/tilt/haml.rb:24:in `evaluate'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/tilt-1.3.3/lib/tilt/template.rb:76:in `render'
	from (irb):116
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/railties-3.1.3/lib/rails/commands/console.rb:45:in `start'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/railties-3.1.3/lib/rails/commands/console.rb:8:in `start'
	from /usr/local/rvm/gems/ruby-1.9.2-p290-patched@newco/gems/railties-3.1.3/lib/rails/commands.rb:40:in `<top (required)>'
	from script/rails:6:in `require'
	from script/rails:6:in `<main>'
>>