Rails can't call method in partial

When I to call a method in a partial I get a ‘undefined local method for
class’ error.

in my view, home.haml

= render "layouts/side"

in my partial /layouts/_side.haml

  - test_method?
    Is true.

In the controller that serves home.haml I put

def test_method?
  return true

I even tried putting the method in the application helper file, no
Any ideas?

You need to use helper_method :test_method? in your Application helper
file. I believe this will give you access to the method inside the view