Depending on a third-party Spree Extension and including relevant migrations while generating a dummy application for testing

Rakefile

desc "Generates a dummy app for testing"
task :test_app do
  ENV['LIB_NAME'] = 'spree_google_base'
  
  puts 'Installing spree-multi-domain migrations [required for testing]'
  dep_path = `bundle show spree_multi_domain`.chomp
  migration_path = File.join(dep_path,'db','migrate')
  dummy_path = File.join(FileUtils.pwd, 'spec', 'dummy', 'db')
  
  FileUtils.mkdir_p(dummy_path)
  FileUtils.cp_r(migration_path, dummy_path)
  
  Rake::Task['common:test_app'].invoke
end