gistfile1.rb

# Checks whether it's a devise mapped resource or not.
def is_devise_resource? #:nodoc:
  raise ActionController::UnknownAction unless devise_mapping
end

# And also

# Attempt to find the mapped route for devise based on request path
def devise_mapping
  @devise_mapping ||= request.env["devise.mapping"]
end

# Unfortunately this does not get set in your specs :(
# So set the following in your before block of controller tests

request.env["devise.mapping"] = Devise.mappings[:user] 
# note the resource for you might be different