rspec_rails_transactional.rb

# In Rspec, gives you:
# before(:all_transactional) {}
#
# Uses nested transactions to correctly rollback :all before blocks
# You *may* need to reload some instance variables in a separate before(:each) block
# All a bit of a hack, but really handy
module RspecRailsTransactions
  def before_all_transactional_parts # :nodoc:
    @before_all_transactional_parts ||= []
  end

  # Overridden from rspec implementation to add :all_transactional
  def before_parts(scope)
    case scope
    when :each; before_each_parts
    when :all; before_all_parts
    when :suite; before_suite_parts
    when :all_transactional; before_all_transactional_parts
    end
  end

  # Based on a combination of run_before_all and run_after_all methods from rspec
  def run_before_all_transactional_parts(success, run_options, instance_variables)
    return [success, instance_variables] if example_group_hierarchy.before_all_transactional_parts.empty?
    example_proxy = ::Spec::Example::ExampleProxy.new("before(:all_transactional)")
    before_all = new(example_proxy)
    before_all.set_instance_variables_from_hash(instance_variables)
    example_group_hierarchy.run_before_all_transactional(before_all)
    [success, before_all.instance_variable_hash]
  rescue Exception => e
    run_options.reporter.example_failed(example_proxy, e)
    [false, before_all.instance_variable_hash]
  end

  # Overridden from the rspec implementation, as it doesn't provide us with necessary hooks
  def run_examples(success, instance_variables, examples, run_options)
    return [success, instance_variables] unless success

    after_all_instance_variables = instance_variables

    ActiveSupport::TestCase.use_transactional_fixtures = false
    ActiveRecord::Base.transaction(:joinable => false) do
      success, instance_variables = run_before_all_transactional_parts(success, run_options, instance_variables)

      if success
        examples.each do |example|
          example_group_instance = new(example, &example_implementations[example])
          # .transaction doesn't work here
          ActiveRecord::Base.connection.create_savepoint
          ActiveRecord::Base.connection.increment_open_transactions
          success &= example_group_instance.execute(run_options, instance_variables)
          ActiveRecord::Base.connection.decrement_open_transactions
          ActiveRecord::Base.connection.rollback_to_savepoint
          after_all_instance_variables = example_group_instance.instance_variable_hash
        end
      end
      raise ActiveRecord::Rollback
    end

    return [success, after_all_instance_variables]
  end
end

module Spec
  module Example
    class ExampleGroupHierarchy < Array
      # Fail fast call was cargo-culted, I need to investigate further
      def run_before_all_transactional(example)
        example.eval_each_fail_fast(before_all_transactional_parts)
      end

      # Not all of the hierachy has necessary been extended with transactional
      # support, so check that each klass responds to the method first
      def before_all_transactional_parts
        @before_all_transactional_parts ||= collect {|klass| klass.before_all_transactional_parts if klass.respond_to?(:before_all_transactional_parts) }.compact.flatten
      end
    end
  end
end