til/rails/include-devise-helpers-in-your-controller-tests.md

Include Devise Helpers In Your Controller Tests

For past versions of Devise, you could include DeviseHelpers as part of controller or request type tests to have access to the sign_in and sign_out helpers.

RSpec.configure do |config|
  config.include Devise::TestHelpers, :type => :controller
end

As of Devise 4.2.0+, the Devise::TestHelpers have been deprecated. The Devise::Test::ControllerHelpers module should instead be included.

RSpec.configure do |config|
  config.include Devise::Test::ControllerHelpers, :type => :controller
end

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