module Devise::Test::IntegrationHelpers

should be signed in with.
* +scope+ - An optional +Symbol+ with the scope where the resource
* +resource+ - The resource that should be authenticated

operation through +Devise::SessionsController#create+.
Signs in a specific resource, mimicking a successful sign in

def sign_in(resource, scope: nil)
  scope ||= Devise::Mapping.find_scope!(resource)
  login_as(resource, scope: scope)
end