class RSpec::Core::ExampleGroup

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

def self.apply?(predicate, filters)
  metadata.apply?(predicate, filters)
end

def self.around_hooks_for(example)
  world.find_hook(:around, :each, self, example) + ancestors.reverse.inject([]){|l,a| l + a.find_hook(:around, :each, self, example)}
end

def self.assign_before_all_ivars(ivars, example_group_instance)
  return if ivars.empty?
  ivars.each { |ivar, val| example_group_instance.instance_variable_set(ivar, val) }
end

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

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

def self.declaration_line_numbers
  @declaration_line_numbers ||= [metadata[:example_group][:line_number]] +
    examples.collect {|e| e.metadata[:line_number]} +
    children.inject([]) {|l,c| l + c.declaration_line_numbers}
end

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

def self.define_nested_shared_group_method(new_name, report_label=nil)
  module_eval(<<-END_RUBY, __FILE__, __LINE__)
    def self.#{new_name}(name, *args, &customization_block)
      shared_block = world.shared_example_groups[name]
      raise "Could not find shared example group named \#{name.inspect}" unless shared_block
      group = describe("#{report_label || "it should behave like"} \#{name}") do
        module_eval_with_args(*args, &shared_block)
        module_eval(&customization_block) if customization_block
      end
      group.metadata[:shared_group_name] = name
      group
    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
  @descendant_filtered_examples ||= filtered_examples + children.inject([]){|l,c| l + c.descendant_filtered_examples}
end

def self.descendants
  @_descendants ||= [self] + children.inject([]) {|list, c| list + c.descendants}
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)
  # 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.ensure_example_groups_are_configured
  unless defined?(@@example_groups_configured)
    RSpec.configuration.configure_mock_framework
    RSpec.configuration.configure_expectation_framework
    @@example_groups_configured = true
  end
end

def self.eval_after_alls(example_group_instance)
  return if descendant_filtered_examples.empty?
  assign_before_all_ivars(before_all_ivars, example_group_instance)
  begin
    run_hook!(:after, :all, example_group_instance)
  rescue => e
    # TODO: come up with a better solution for this.
    RSpec.configuration.reporter.message <<-EOS
or occurred in an after(:all) hook.
class}: #{e.message}
rred at #{e.backtrace.first}
  EOS
  end
  world.run_hook_filtered(:after, :all, self, example_group_instance)
end

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

def self.eval_around_eachs(example, initial_procsy)
  example.around_hooks.reverse.inject(initial_procsy) do |procsy, around_hook|
    Example.procsy(procsy.metadata) do
      example.example_group_instance.instance_eval_with_args(procsy, &around_hook)
    end
  end
end

def self.eval_before_alls(example_group_instance)
  return if descendant_filtered_examples.empty?
  assign_before_all_ivars(superclass.before_all_ivars, example_group_instance)
  world.run_hook_filtered(:before, :all, self, example_group_instance)
  run_hook!(:before, :all, example_group_instance)
  store_before_all_ivars(example_group_instance)
end

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

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

def self.fail_fast?
  RSpec.configuration.fail_fast?
end

def self.fail_filtered_examples(exception, reporter)
  filtered_examples.each { |example| example.fail_fast(reporter, exception) }
  children.each do |child|
    reporter.example_group_started(child)
    child.fail_filtered_examples(exception, reporter)
    reporter.example_group_finished(child)
  end
  false
end

def self.filtered_examples
  world.filtered_examples[self]
end

def self.include_context(name)
  module_eval(&world.shared_example_groups[name])
end

def self.metadata
  @metadata if defined?(@metadata)
end

def self.register
  world.register(self)
end

def self.run(reporter)
  if RSpec.wants_to_quit
    RSpec.clear_remaining_example_groups if top_level?
    return
  end
  reporter.example_group_started(self)
  begin
    eval_before_alls(new)
    result_for_this_group = run_examples(reporter)
    results_for_descendants = children.map {|child| child.run(reporter)}.all?
    result_for_this_group && results_for_descendants
  rescue Exception => ex
    fail_filtered_examples(ex, reporter)
  ensure
    eval_after_alls(new)
    before_all_ivars.clear
    reporter.example_group_finished(self)
  end
end

def self.run_examples(reporter)
  filtered_examples.map do |example|
    next if RSpec.wants_to_quit
    instance = new
    set_ivars(instance, before_all_ivars)
    succeeded = example.run(instance, reporter)
    RSpec.wants_to_quit = true if fail_fast? && !succeeded
    succeeded
  end.all?
end

def self.set_it_up(*args)
  # Ruby 1.9 has a bug that can lead to infinite recursion and a
  # SystemStackError if you include a module in a superclass after
  # including it in a subclass: https://gist.github.com/845896
  # To prevent this, we must include any modules in RSpec::Core::ExampleGroup
  # before users create example groups and have a chance to include
  # the same module in a subclass of RSpec::Core::ExampleGroup.
  # So we need to configure example groups here.
  ensure_example_groups_are_configured
  symbol_description = args.shift if args.first.is_a?(Symbol)
  args << build_metadata_hash_from(args)
  args.unshift(symbol_description) if symbol_description
  @metadata = RSpec::Core::Metadata.new(superclass_metadata).process(*args)
  world.configure_group(self)
end

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

def self.store_before_all_ivars(example_group_instance)
  return if example_group_instance.instance_variables.empty?
  example_group_instance.instance_variables.each { |ivar| 
    before_all_ivars[ivar] = example_group_instance.instance_variable_get(ivar)
  }
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
  @superclass_metadata ||= self.superclass.respond_to?(:metadata) ? self.superclass.metadata : nil
end

def self.top_level?
  @top_level ||= superclass == ExampleGroup
end

def self.top_level_description
  ancestors.last.description
end

def self.world
  RSpec.world
end

def described_class
  self.class.described_class
end

def instance_eval_with_rescue(&hook)
  begin
    instance_eval(&hook)
  rescue Exception => e
    raise unless example
    example.set_exception(e)
  end
end

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