I wanted a #login method in test_helper that would allow me to easily login from any of my functional tests. However, the #post method won't allow you to set a different controller than the one in the @controller instance variable that's defined in your test's #setup. Well, by looking at how the #process method works, you can see that it just grabs the controller from @controller. Redefine that, and you're good to go:

old_controller = @controller
@controller = LoginController.new
post(
  :attempt_login,
  {:user => {:name => 'joe', :password => 'password'}}
)
@controller = old_controller

If you have several login methods, such as a #login_admin and #login_regular, you could make a wrapper to reduce duplication:

def wrap_with_controller( new_controller = LoginController )
  old_controller = @controller
  @controller = new_controller.new
  yield
  @controller = old_controller
end

def login_admin
  wrap_with_controller do
    post(
      :attempt_login,
      {:user => {:name => 'root', :password => 'password'}}
    )
  end
end

def login_regular
  wrap_with_controller do
    post(
      :attempt_login,
      {:user => {:name => 'joe', :password => 'password'}}
    )
  end
end

I frequently have to use methods such as 'radio_button' and 'check_box_tag' when I don't have an object with a method that will automatically determine the value of the input field. Therefore, I have to check to see if a certain parameter has been passed, and if so, if the parameter's value matches that of the input's value. This method does that.

It's designed to be used in a Rails helper. You can either pass it the object, method, and value (the same parameters as, for example, radio_button) or name and value (the same parameters as radio_button_tag).

def checked?( *args )
  if args.length == 3
    object, method, value = args
    if params[object] && params[object][method] && params[object][method] == value
      'checked'
    end
  elsif args.length == 2
    name, value = args
    if params[name] && params[name] == value
      true
    end
  end
end

Here's an example usage:

<%= radio_button 'person', 'age', '12', :checked => checked?( 'person', 'age', '12' ) %>

If params[:person][:age] exists and it equals '12', then 'checked?' returns 'checked'; otherwise, it returns nil.