class RuboCop::Cop::Layout::CommentIndentation

Checks the indentation of comments.

@example

# bad
  # comment here
def method_name
end

  # comment here
a = 'hello'

# yet another comment
  if true
    true
  end

# good
# comment here
def method_name
end

# comment here
a = 'hello'

# yet another comment
if true
  true
end

@example AllowForAlignment: false (default)

# bad
a = 1 # A really long comment
      # spanning two lines.

# good
# A really long comment spanning one line.
a = 1

@example AllowForAlignment: true

# good
a = 1 # A really long comment
      # spanning two lines.

Constants

MSG

Public Instance Methods

on_new_investigation() click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 55
def on_new_investigation
  processed_source.comments.each_with_index { |comment, ix| check(comment, ix) }
end

Private Instance Methods

autocorrect(corrector, comment) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 61
def autocorrect(corrector, comment)
  autocorrect_preceding_comments(corrector, comment)

  autocorrect_one(corrector, comment)
end
autocorrect_one(corrector, comment) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 88
def autocorrect_one(corrector, comment)
  AlignmentCorrector.correct(corrector, processed_source, comment, @column_delta)
end
autocorrect_preceding_comments(corrector, comment) click to toggle source

Corrects all comment lines that occur immediately before the given comment and have the same indentation. This is to avoid a long chain of correcting, saving the file, parsing and inspecting again, and then correcting one more line, and so on.

# File lib/rubocop/cop/layout/comment_indentation.rb, line 71
def autocorrect_preceding_comments(corrector, comment)
  comments = processed_source.comments
  index = comments.index(comment)

  comments[0..index]
    .reverse_each
    .each_cons(2)
    .take_while { |below, above| should_correct?(above, below) }
    .map { |_, above| autocorrect_one(corrector, above) }
end
check(comment, comment_index) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 92
def check(comment, comment_index)
  return unless own_line_comment?(comment)

  next_line = line_after_comment(comment)
  correct_comment_indentation = correct_indentation(next_line)
  column = comment.loc.column

  @column_delta = correct_comment_indentation - column
  return if @column_delta.zero?

  if two_alternatives?(next_line)
    # Try the other
    correct_comment_indentation += configured_indentation_width
    # We keep @column_delta unchanged so that autocorrect changes to
    # the preferred style of aligning the comment with the keyword.
    return if column == correct_comment_indentation
  end

  return if correctly_aligned_with_preceding_comment?(comment_index, column)

  add_offense(comment, message: message(column, correct_comment_indentation)) do |corrector|
    autocorrect(corrector, comment)
  end
end
correct_indentation(next_line) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 145
def correct_indentation(next_line)
  return 0 unless next_line

  indentation_of_next_line = next_line =~ /\S/
  indentation_of_next_line + if less_indented?(next_line)
                               configured_indentation_width
                             else
                               0
                             end
end
correctly_aligned_with_preceding_comment?(comment_index, column) click to toggle source

Returns true if: a) the cop is configured to allow extra indentation for alignment, and b) the currently inspected comment is aligned with the nearest preceding end-of-line

comment.
# File lib/rubocop/cop/layout/comment_indentation.rb, line 121
def correctly_aligned_with_preceding_comment?(comment_index, column)
  return false unless cop_config['AllowForAlignment']

  processed_source.comments[0...comment_index].reverse_each do |other_comment|
    return other_comment.loc.column == column unless own_line_comment?(other_comment)
  end

  false
end
less_indented?(line) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 156
def less_indented?(line)
  /^\s*(end\b|[)}\]])/.match?(line)
end
line_after_comment(comment) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 140
def line_after_comment(comment)
  lines = processed_source.lines
  lines[comment.loc.line..].find { |line| !line.blank? }
end
message(column, correct_comment_indentation) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 131
def message(column, correct_comment_indentation)
  format(MSG, column: column, correct_comment_indentation: correct_comment_indentation)
end
own_line_comment?(comment) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 135
def own_line_comment?(comment)
  own_line = processed_source.lines[comment.loc.line - 1]
  /\A\s*#/.match?(own_line)
end
should_correct?(preceding_comment, reference_comment) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 82
def should_correct?(preceding_comment, reference_comment)
  loc = preceding_comment.loc
  ref_loc = reference_comment.loc
  loc.line == ref_loc.line - 1 && loc.column == ref_loc.column
end
two_alternatives?(line) click to toggle source
# File lib/rubocop/cop/layout/comment_indentation.rb, line 160
def two_alternatives?(line)
  /^\s*(else|elsif|when|rescue|ensure)\b/.match?(line)
end