class RSpec::Core::ExampleGroup

def self.all_apply?(filters)
  metadata.all_apply?(filters)
end

def self.ancestors
  @_ancestors ||= super().select {|a| a < RSpec::Core::ExampleGroup}
end

def self.before_all_ivars
  @before_all_ivars ||= {}
end

def self.children
  @children ||= []
end

def self.clear_ivars(instance)
  instance.instance_variables.each { |ivar| instance.send(:remove_instance_variable, ivar) }
end

def self.clear_memoized(instance)
  instance.__memoized.clear
end

def self.declaration_line_numbers
  [metadata[:example_group][:line_number]] +
    examples.collect {|e| e.metadata[:line_number]} +
    children.collect {|c| c.declaration_line_numbers}.flatten
end

def self.define_example_method(name, extra_options={})
  module_eval(<<-END_RUBY, __FILE__, __LINE__)
    def self.#{name}(desc=nil, options={}, &block)
      options.update(:pending => true) unless block
      options.update(:caller => caller)
      options.update(#{extra_options.inspect})
      examples << RSpec::Core::Example.new(self, desc, options, block)
      examples.last
    end
  END_RUBY
end

def self.delegate_to_metadata(*names)
  names.each do |name|
    define_method name do
      metadata[:example_group][name]
    end
  end
end

def self.descendant_filtered_examples
  filtered_examples + children.collect{|c| c.descendant_filtered_examples}
end

def self.descendants
  [self] + children.collect {|c| c.descendants}.flatten
end

def self.describe(*args, &example_group_block)
  @_subclass_count ||= 0
  @_subclass_count += 1
  args << {} unless args.last.is_a?(Hash)
  args.last.update(:example_group_block => example_group_block)
  args.last.update(:caller => caller)
  # TODO 2010-05-05: Because we don't know if const_set is thread-safe
  child = const_set(
    "Nested_#{@_subclass_count}",
    subclass(self, args, &example_group_block)
  )
  children << child
  child
end

def self.eval_after_alls(example)
  return if descendant_filtered_examples.empty?
  before_all_ivars.each { |ivar, val| example.instance_variable_set(ivar, val) }
  ancestors.each {|ancestor| ancestor.run_hook!(:after, :all, example) }
  world.run_hook_filtered(:after, :all, self, example)
end

def self.eval_after_eachs(example)
  ancestors.each { |ancestor| ancestor.run_hook(:after, :each, example, :reverse => true) }
  world.run_hook_filtered(:after, :each, self, example)
end

def self.eval_before_alls(example)
  return if descendant_filtered_examples.empty?
  superclass.before_all_ivars.each { |ivar, val| example.instance_variable_set(ivar, val) }
  world.run_hook_filtered(:before, :all, self, example)
  run_hook!(:before, :all, example, :reverse => true)
  example.instance_variables.each { |ivar| before_all_ivars[ivar] = example.instance_variable_get(ivar) }
end

def self.eval_before_eachs(example)
  world.run_hook_filtered(:before, :each, self, example)
  ancestors.reverse.each { |ancestor| ancestor.run_hook(:before, :each, example) }
end

def self.examples
  @examples ||= []
end

def self.extended_modules #:nodoc:
  @extended_modules ||= ancestors.select { |mod| mod.class == Module } - [ Object, Kernel ]
end

def self.filtered_examples
  world.filtered_examples[self]
end

def self.inherited(klass)
  RSpec::Core::Runner.autorun
  world.example_groups << klass if klass.superclass == ExampleGroup
end

def self.it_should_behave_like(*names)
  names.each do |name|
    begin
      module_eval &RSpec.world.shared_example_groups[name]
    rescue ArgumentError
      raise "Could not find shared example group named #{name.inspect}"
    end
  end
end

def self.metadata
  @metadata 
end

def self.mixins
  @mixins ||= {
    :include => included_modules,
    :extend => extended_modules
  }
end

def self.run(reporter)
  example_group_instance = new
  reporter.add_example_group(self)
  begin
    eval_before_alls(example_group_instance)
    result_for_this_group = run_examples(example_group_instance, reporter)
    results_for_descendants = children.map {|child| child.run(reporter)}.all?
    result_for_this_group && results_for_descendants
  ensure
    eval_after_alls(example_group_instance)
  end
end

def self.run_examples(instance, reporter)
  filtered_examples.map do |example|
    begin
      set_ivars(instance, before_all_ivars)
      example.run(instance, reporter)
    ensure
      clear_ivars(instance)
      clear_memoized(instance)
    end
  end.all?
end

def self.set_it_up(*args)
  @metadata = RSpec::Core::Metadata.new(superclass_metadata).process(*args)
  world.find_modules(self).each do |include_or_extend, mod, opts|
    send(include_or_extend, mod) unless mixins[include_or_extend].include?(mod)
  end
end

def self.set_ivars(instance, ivars)
  ivars.each {|name, value| instance.instance_variable_set(name, value)}
end

def self.subclass(parent, args, &example_group_block)
  subclass = Class.new(parent)
  subclass.set_it_up(*args) 
  subclass.module_eval(&example_group_block) if example_group_block
  subclass
end

def self.superclass_metadata
  self.superclass.respond_to?(:metadata) ? self.superclass.metadata : nil
end

def self.to_s
  self == RSpec::Core::ExampleGroup ? 'RSpec::Core::ExampleGroup' : name
end

def self.top_level_description
  ancestors.last.description
end

def self.world
  RSpec.world
end

def described_class
  self.class.describes
end

def running_example
  RSpec.deprecate('running_example', 'example')
  example
end