module RSpec::Core::Metadata::MetadataHash

def [](key)
  return super if has_key?(key)
  case key
  when :location
    store(:location, location)
  when :file_path, :line_number
    file_path, line_number = file_and_line_number
    store(:file_path, file_path)
    store(:line_number, line_number)
    super
  when :execution_result
    store(:execution_result, {})
  when :describes
    store(:describes, described_class_for(self))
  when :full_description
    store(:full_description, full_description_for(self))
  when :description
    store(:description, build_description_from(*self[:description_args]))
  else
    super
  end
end