class RuboCop::Cop::Layout::RedundantLineBreak

Checks whether certain expressions, e.g. method calls, that could fit completely on a single line, are broken up into multiple lines unnecessarily.

@example any configuration

# bad
foo(
  a,
  b
)

puts 'string that fits on ' \
     'a single line'

things
  .select { |thing| thing.cond? }
  .join('-')

# good
foo(a, b)

puts 'string that fits on a single line'

things.select { |thing| thing.cond? }.join('-')

@example InspectBlocks: false (default)

# good
foo(a) do |x|
  puts x
end

@example InspectBlocks: true

# bad
foo(a) do |x|
  puts x
end

# good
foo(a) { |x| puts x }

Constants

MSG

Public Instance Methods

on_send(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 51
def on_send(node)
  # Include "the whole expression".
  node = node.parent while convertible_block?(node) ||
                           node.parent.is_a?(RuboCop::AST::BinaryOperatorNode) ||
                           node.parent&.send_type?

  return unless offense?(node) && !part_of_ignored_node?(node)

  register_offense(node)
end

Private Instance Methods

check_assignment(node, _rhs) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 64
def check_assignment(node, _rhs)
  return unless offense?(node)

  register_offense(node)
end
comment_within?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 113
def comment_within?(node)
  processed_source.comments.map(&:loc).map(&:line).any? do |comment_line_number|
    comment_line_number >= node.first_line && comment_line_number <= node.last_line
  end
end
configured_to_not_be_inspected?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 83
def configured_to_not_be_inspected?(node)
  return true if other_cop_takes_precedence?(node)

  !cop_config['InspectBlocks'] && (node.block_type? ||
                                   node.each_descendant(:block).any?(&:multiline?))
end
convertible_block?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 107
def convertible_block?(node)
  parent = node.parent
  parent&.block_type? && node == parent.send_node &&
    (node.parenthesized? || !node.arguments?)
end
max_line_length() click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 133
def max_line_length
  config.for_cop('Layout/LineLength')['Max']
end
offense?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 77
def offense?(node)
  return false if configured_to_not_be_inspected?(node)

  node.multiline? && !too_long?(node) && suitable_as_single_line?(node)
end
other_cop_takes_precedence?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 90
def other_cop_takes_precedence?(node)
  single_line_block_chain_enabled? && node.each_descendant(:block).any? do |block_node|
    block_node.parent.send_type? && block_node.parent.loc.dot && !block_node.multiline?
  end
end
register_offense(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 70
def register_offense(node)
  add_offense(node) do |corrector|
    corrector.replace(node.source_range, to_single_line(node.source).strip)
  end
  ignore_node(node)
end
single_line_block_chain_enabled?() click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 96
def single_line_block_chain_enabled?
  @config.for_cop('Layout/SingleLineBlockChain')['Enabled']
end
suitable_as_single_line?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 100
def suitable_as_single_line?(node)
  !comment_within?(node) &&
    node.each_descendant(:if, :case, :kwbegin, :def).none? &&
    node.each_descendant(:dstr, :str).none?(&:heredoc?) &&
    node.each_descendant(:begin).none? { |b| !b.single_line? }
end
to_single_line(source) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 124
def to_single_line(source)
  source
    .gsub(/" *\\\n\s*'/, %q(" + ')) # Double quote, backslash, and then single quote
    .gsub(/' *\\\n\s*"/, %q(' + ")) # Single quote, backslash, and then double quote
    .gsub(/(["']) *\\\n\s*\1/, '')  # Double or single quote, backslash, then same quote
    .gsub(/\n\s*(?=\.\w)/, '')      # Extra space within method chaining
    .gsub(/\s*\\?\n\s*/, ' ')       # Any other line break, with or without backslash
end
too_long?(node) click to toggle source
# File lib/rubocop/cop/layout/redundant_line_break.rb, line 119
def too_long?(node)
  lines = processed_source.lines[(node.first_line - 1)...node.last_line]
  to_single_line(lines.join("\n")).length > max_line_length
end