class ProcessExecuter::Options::SpawnOptions

def define_options
  [*super, *SPAWN_OPTIONS].freeze
end

def include_spawn_option?(option_key, value)
  return false if value == :not_set
  redirection?(option_key) || SPAWN_OPTIONS.any? { |o| o.name == option_key }
end

def redirection?(option_key)
  test = ->(key) { %i[in out err].include?(key) || key.is_a?(Integer) || (key.is_a?(IO) && !key.fileno.nil?) }
  test.call(option_key) || (option_key.is_a?(Array) && option_key.all? { |key| test.call(key) })
end

def spawn_options
  {}.tap do |spawn_options|
    options.each do |option_key, value|
      spawn_options[option_key] = value if include_spawn_option?(option_key, value)
    end
  end
end

def std_redirection?(option_key, symbol, fileno)
  test = ->(key) { key == symbol || key == fileno || (key.is_a?(IO) && key.fileno == fileno) }
  test.call(option_key) || (option_key.is_a?(Array) && option_key.any? { |key| test.call(key) })
end

def stderr_redirection?(option_key) = std_redirection?(option_key, :err, 2)

def stderr_redirection_key
  options.keys.find { |option_key| option_key if stderr_redirection?(option_key) }
end

def stderr_redirection_value
  options[stderr_redirection_key]
end

def stdout_redirection?(option_key) = std_redirection?(option_key, :out, 1)

def stdout_redirection_key
  options.keys.find { |option_key| option_key if stdout_redirection?(option_key) }
end

def stdout_redirection_value
  options[stdout_redirection_key]
end

def valid_option?(option_key)
  super || redirection?(option_key)
end