class RuboCop::Cop::Style::SingleLineBlockParams

def args_match?(method_name, args)
  actual_args = args.flat_map(&:to_a)
  # Prepending an underscore to mark an unused parameter is allowed, so
  # we remove any leading underscores before comparing.
  actual_args_no_underscores = actual_args.map do |arg|
    arg.to_s.sub(/^_+/, '')
  end
  actual_args_no_underscores == target_args(method_name)
end

def message(method_name)
  args = target_args(method_name).join(', ')
  "Name `#{method_name}` block params `|#{args}|`."
end

def method_names
  methods.map { |e| e.keys.first.to_sym }
end

def methods
  cop_config['Methods']
end

def on_block(node)
  # we care only for single line blocks
  return unless block_length(node) == 0
  method_node, args_node, _body_node = *node
  receiver, method_name, _method_args = *method_node
  # discard other scenarios
  return unless receiver
  return unless method_names.include?(method_name)
  # discard cases with argument destructuring
  args = *args_node
  return true unless args.all? { |n| n.type == :arg }
  return if args_match?(method_name, args)
  add_offense(args_node, :expression, message(method_name))
end

def target_args(method_name)
  method_name = method_name.to_s
  method_hash = methods.find { |m| m.keys.first == method_name }
  method_hash[method_name]
end