module RuboCop::Cop::Util

This module contains a collection of useful utility methods. rubocop:disable Metrics/ModuleLength

Constants

LINE_BEGINS_REGEX_CACHE
LITERAL_REGEX

Match literal regex characters, not including anchors, character classes, alternatives, groups, repetitions, references, etc

MAX_LINE_BEGINS_REGEX_INDEX

Arbitrarily chosen value, should be enough to cover the most nested source code in real world projects.

Public Instance Methods

add_parentheses(node, corrector) click to toggle source

rubocop:disable Metrics/AbcSize, Metrics/MethodLength

# File lib/rubocop/cop/util.rb, line 39
def add_parentheses(node, corrector)
  if node.args_type?
    arguments_range = node.source_range
    args_with_space = range_with_surrounding_space(arguments_range, side: :left)
    leading_space = range_between(args_with_space.begin_pos, arguments_range.begin_pos)
    corrector.replace(leading_space, '(')
    corrector.insert_after(arguments_range, ')')
  elsif !node.respond_to?(:arguments)
    corrector.wrap(node, '(', ')')
  elsif node.arguments.empty?
    corrector.insert_after(node, '()')
  else
    args_begin = args_begin(node)

    corrector.remove(args_begin)
    corrector.insert_before(args_begin, '(')
    corrector.insert_after(args_end(node), ')')
  end
end
any_descendant?(node, *types) { |descendant| ... } click to toggle source

rubocop:enable Metrics/AbcSize, Metrics/MethodLength

# File lib/rubocop/cop/util.rb, line 60
def any_descendant?(node, *types)
  if block_given?
    node.each_descendant(*types) do |descendant|
      return true if yield(descendant)
    end
  else
    # Use a block version to avoid allocating enumerators.
    node.each_descendant do # rubocop:disable Lint/UnreachableLoop
      return true
    end
  end

  false
end
args_begin(node) click to toggle source
# File lib/rubocop/cop/util.rb, line 75
def args_begin(node)
  loc = node.loc
  selector = if node.super_type? || node.yield_type?
               loc.keyword
             elsif node.def_type? || node.defs_type?
               loc.name
             else
               loc.selector
             end
  selector.end.resize(1)
end
args_end(node) click to toggle source
# File lib/rubocop/cop/util.rb, line 87
def args_end(node)
  node.source_range.end
end
begins_its_line?(range) click to toggle source
# File lib/rubocop/cop/util.rb, line 108
def begins_its_line?(range)
  if (regex = LINE_BEGINS_REGEX_CACHE[range.column])
    range.source_line.match?(regex)
  else
    range.source_line.index(/\S/) == range.column
  end
end
comment_line?(line_source) click to toggle source

This is a bad API

# File lib/rubocop/cop/util.rb, line 17
def comment_line?(line_source)
  /^\s*#/.match?(line_source)
end
comment_lines?(node) click to toggle source

@deprecated Use ‘ProcessedSource#line_with_comment?`, `contains_comment?` or similar

# File lib/rubocop/cop/util.rb, line 22
      def comment_lines?(node)
        warn Rainbow(<<~WARNING).yellow, uplevel: 1
          `comment_lines?` is deprecated. Use `ProcessedSource#line_with_comment?`, `contains_comment?` or similar instead.
        WARNING

        processed_source[line_range(node)].any? { |line| comment_line?(line) }
      end
double_quotes_required?(string) click to toggle source

If converting a string to Ruby string literal source code, must double quotes be used?

# File lib/rubocop/cop/util.rb, line 134
def double_quotes_required?(string)
  # Double quotes are required for strings which either:
  # - Contain single quotes
  # - Contain non-printable characters, which must use an escape

  # Regex matches IF there is a ' or there is a \\ in the string that is
  # not preceded/followed by another \\ (e.g. "\\x34") but not "\\\\".
  /'|(?<! \\) \\{2}* \\ (?![\\"])/x.match?(string)
end
escape_string(string) click to toggle source
# File lib/rubocop/cop/util.rb, line 148
def escape_string(string)
  string.inspect[1..-2].tap { |s| s.gsub!('\\"', '"') }
end
first_part_of_call_chain(node) click to toggle source

Returns, for example, a bare ‘if` node if the given node is an `if` with calls chained to the end of it.

# File lib/rubocop/cop/util.rb, line 118
def first_part_of_call_chain(node)
  while node
    case node.type
    when :send
      node = node.receiver
    when :block
      node = node.send_node
    else
      break
    end
  end
  node
end
indent(node, offset: 0) click to toggle source
# File lib/rubocop/cop/util.rb, line 185
def indent(node, offset: 0)
  ' ' * (node.loc.column + offset)
end
interpret_string_escapes(string) click to toggle source
# File lib/rubocop/cop/util.rb, line 165
def interpret_string_escapes(string)
  StringInterpreter.interpret(string)
end
line(node_or_range) click to toggle source
# File lib/rubocop/cop/util.rb, line 169
def line(node_or_range)
  if node_or_range.respond_to?(:line)
    node_or_range.line
  elsif node_or_range.respond_to?(:loc)
    node_or_range.loc.line
  end
end
line_range(node) click to toggle source
# File lib/rubocop/cop/util.rb, line 30
def line_range(node)
  node.first_line..node.last_line
end
needs_escaping?(string) click to toggle source
# File lib/rubocop/cop/util.rb, line 144
def needs_escaping?(string)
  double_quotes_required?(escape_string(string))
end
on_node(syms, sexp, excludes = []) { |sexp| ... } click to toggle source
# File lib/rubocop/cop/util.rb, line 91
def on_node(syms, sexp, excludes = [], &block)
  return to_enum(:on_node, syms, sexp, excludes) unless block

  yield sexp if include_or_equal?(syms, sexp.type)
  return if include_or_equal?(excludes, sexp.type)

  sexp.each_child_node { |elem| on_node(syms, elem, excludes, &block) }
end
parentheses?(node) click to toggle source
# File lib/rubocop/cop/util.rb, line 34
def parentheses?(node)
  node.loc.respond_to?(:end) && node.loc.end&.is?(')')
end
same_line?(node1, node2) click to toggle source
# File lib/rubocop/cop/util.rb, line 177
def same_line?(node1, node2)
  line1 = line(node1)
  line2 = line(node2)
  return false unless line1 && line2

  line1 == line2
end
to_string_literal(string) click to toggle source
# File lib/rubocop/cop/util.rb, line 152
def to_string_literal(string)
  if needs_escaping?(string) && compatible_external_encoding_for?(string)
    string.inspect
  else
    # In a single-quoted strings, double quotes don't need to be escaped
    "'#{string.gsub('\\') { '\\\\' }.gsub('\"', '"')}'"
  end
end
to_supported_styles(enforced_style) click to toggle source
# File lib/rubocop/cop/util.rb, line 191
def to_supported_styles(enforced_style)
  @to_supported_styles_cache[enforced_style] ||=
    enforced_style.sub(/^Enforced/, 'Supported').sub('Style', 'Styles')
end
trim_string_interpolation_escape_character(str) click to toggle source
# File lib/rubocop/cop/util.rb, line 161
def trim_string_interpolation_escape_character(str)
  str.gsub(/\\\#\{(.*?)\}/) { "\#{#{Regexp.last_match(1)}}" }
end

Private Instance Methods

compatible_external_encoding_for?(src) click to toggle source
# File lib/rubocop/cop/util.rb, line 198
def compatible_external_encoding_for?(src)
  src = src.dup if RUBY_ENGINE == 'jruby'
  src.force_encoding(Encoding.default_external).valid_encoding?
end
include_or_equal?(source, target) click to toggle source
# File lib/rubocop/cop/util.rb, line 203
def include_or_equal?(source, target)
  source == target || (source.is_a?(Array) && source.include?(target))
end