Class: RuboCop::Cop::Style::ConcatArrayLiterals

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 110

def comment_in?(range)
  processed_source.each_comment_in_lines(range.line..range.last_line).any? do |comment|
    range.contains?(comment.source_range)
  end
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 80

def offense_range(node)
  node.loc.selector.join(node.source_range.end)
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 76

alias on_csend on_send

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 43

def on_send(node)
  return if node.arguments.empty?
  return unless node.arguments.all?(&:array_type?)

  offense = offense_range(node)
  current = offense.source

  if (use_percent_literal = node.arguments.any?(&:percent_literal?))
    if percent_literals_includes_only_basic_literals?(node)
      prefer = preferred_method(node)
      message = format(MSG, prefer: prefer, current: current)
    else
      message = format(MSG_FOR_PERCENT_LITERALS, current: current)
    end
  else
    prefer = preferred_method(node)
    message = format(MSG, prefer: prefer, current: current)
  end

  add_offense(offense, message: message) do |corrector|
    if use_percent_literal
      next unless prefer

      rebuild_call(corrector, offense, prefer)
    elsif node.arguments.any? { |argument| argument.children.empty? }
      # In-place bracket removal would leave dangling commas (e.g.
      # `concat([], [b])` -> `push(, b)`), so rebuild the call instead.
      rebuild_call(corrector, offense, preferred_method(node))
    else
      remove_brackets(corrector, node)
    end
  end
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 97

def percent_literals_includes_only_basic_literals?(node)
  node.arguments.select(&:percent_literal?).all? do |arg|
    arg.children.all? { |child| child.type?(:str, :sym) }
  end
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 84

def preferred_method(node)
  new_arguments =
    node.arguments.flat_map do |arg|
      if arg.percent_literal?
        arg.children.map { |child| child.value.inspect }
      else
        arg.children.map(&:source)
      end
    end.join(', ')

  "push(#{new_arguments})"
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 103

def rebuild_call(corrector, offense, replacement)
  # The comments inside the call would be lost.
  return if comment_in?(offense)

  corrector.replace(offense, replacement)
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 116

def remove_brackets(corrector, node)
  closing_ranges = node.arguments.map { |argument| closing_bracket_range(node, argument) }
  # A comment or a heredoc body there can't be moved out of the way.
  return unless closing_ranges.all? { |range| range.source.match?(/\A[\s,]*\]\z/) }

  replace_selector(corrector, node)

  node.arguments.zip(closing_ranges) do |argument, closing_range|
    corrector.remove(argument.loc.begin)
    corrector.remove(closing_range)
  end
end

# File 'lib/rubocop/cop/style/concat_array_literals.rb', line 138

def replace_selector(corrector, node)
  if node.parenthesized? || node.single_line?
    corrector.replace(node.loc.selector, 'push')
  else
    range = node.loc.selector.join(node.first_argument.source_range.begin)

    corrector.replace(range, 'push(')
    corrector.insert_after(node.last_argument.loc.end, ')')
  end
end