RSpec rake tasks

example_rake_spec.rb

# frozen_string_literal: true

require 'rake_helper'

describe 'example rake task' do
  describe '#run', rake: {
    file_name: 'file_name_of_rake_task',
    engine: Authentication::Engine
  } do
      it '' do; end
    end
  end
  
  describe '#run', rake: 'file_name_of_rake_task' do
      it '' do; end
    end
  end
end

rake_helpers.rb

# frozen_string_literal: true

require 'rake'

RSpec.configure do |config|
  config.before(:each, rake: true) do |example|
    options = example.metadata[:rake]

    file_name = options.is_a?(Hash) ? options[:file_name] : options
    engine = options.try(:dig, :engine) || Rails

    Rake.application = Rake::Application.new
    Rake.application.rake_require "lib/tasks/#{file_name}", [engine.root.to_s], []
    Rake::Task.define_task(:environment)
  end
end