SessionMock: a small module to help mocking sessions within Hanami in feature specs

session_mock.rb

# Session mocking may be used in feature tests to mock a session
# since it's not possible to inject the session through params or
# direct injection.
#
# SessionMock is a module that may be included
# in `Hanami::Web::Action` to override the session
# in feature specs.
#
# Usage (in the controller action):
#
#     module Web::Controllers::Home::Index
#       include Web::Action
#       include SessionMock
#     end
#
# Usage (in the spec):
#
#     before { SessionMock.enable_and_set!(session }
#     after { SessionMock.disable! }
#     let(:session) { { key: value } }
#
# TODO: see if it can be added automatically to
#   `Web::Action` modules.
#
module SessionMock
  @enabled = false

  if ENV['HANAMI_ENV'] == 'test'
    def session
      return super unless SessionMock.enabled?
      SessionMock.get
    end
  end

  def self.enabled?
    @enabled
  end

  def self.get
    @value
  end

  def self.set(session)
    @value = session
  end

  # TODO: see how to enable/disable session mock for feature
  #   tests automatically.
  def self.enable_and_set!(session)
    @enabled = true
    set(session)
  end

  def self.disable!
    @enabled = false
  end
end