# File lib/spork/test_framework.rb, line 40
  def self.factory(output = STDOUT, error = STDERR, beginning_with = nil)
    if beginning_with
      @klass = supported_test_frameworks(beginning_with).first
      raise(NoFrameworkMatched.new(beginning_with)) if @klass.nil?
      raise(FrameworkNotAvailable.new(@klass)) unless @klass.available?
    else
      @klass = available_test_frameworks.first
      raise(NoFrameworksAvailable.new) unless @klass
    end
    @klass.new(output, error)
  end