Using a container to manage tests components

spec_helper.rb

# frozen_string_literal: true

require_relative '../system/my_app/container'

module MyApp
  module Tests
    class Container < Dry::System::Container
      use :env, inferrer: -> { 'test' }

      configure do
        config.name = :my_app_tests
      end

      import core: MyApp::Container

      load_paths! 'spec'
    end
  end
end

MyApp::Tests::Container.boot :rspec do |system|
  init do
    require 'rspec/collection_matchers'

    RSpec.configure do |config|
      config.expect_with :rspec do |expectations|
        expectations.include_chain_clauses_in_custom_matcher_descriptions = true
      end

      config.mock_with :rspec do |mocks|
        mocks.verify_partial_doubles = true
      end

      config.default_formatter = 'doc' if config.files_to_run.one?
      config.disable_monkey_patching!
      config.shared_context_metadata_behavior = :apply_to_host_groups
      config.warnings = false

      config.define_derived_metadata do |meta|
        meta[:aggregate_failures] = true
      end

      config.order = :random
      Kernel.srand config.seed
    end
  end
end

MyApp::Tests::Container.boot :rack_test do
  init do
    use :rspec

    require 'rack/test'
    require 'my_app/web'

    RSpec.configure do |config|
      config.include Rack::Test::Methods, type: :request

      config.include((Module.new do
        def app
          MyApp::Web.freeze.app
        end
      end), type: :request)
    end
  end
end

MyApp::Tests::Container.boot :database_cleaner do |system|
  init do
    use :rspec

    require 'database_cleaner'

    DatabaseCleaner.allow_remote_database_url = true

    database_cleaner = DatabaseCleaner[
      :sequel, connection: system[:'core.persistence.database']
    ]

    RSpec.configure do |config|
      config.before :suite do
        database_cleaner.strategy = :deletion
        database_cleaner.start
        database_cleaner.strategy.clean
      end

      config.around do |example|
        database_cleaner.cleaning do
          example.run
        end
      end
    end
  end
end

MyApp::Tests::Container.boot :factory do |system|
  init do
    use :rspec

    require 'rom-factory'

    factory = ROM::Factory.configure do |config|
      config.rom = system[:'core.persistence.rom']
    end

    factory.define :provider do |f|
      f.title { fake(:company, :name) }

      f.created_at { Time.now }
      f.updated_at { Time.now }
    end

    register :factory, factory

    RSpec.configure do |config|
      config.include(Module.new do
        def factory
          MyApp::Tests::Container[:factory]
        end
      end)
    end
  end
end

MyApp::Tests::Container.finalize!

Usually spec_helper.rb is a mess of global constants, rspec configs and $LOAD_PATH preparations. Time to change it!