module RuboCop::Cop::Util

This module contains a collection of useful utility methods.

Constants

LITERAL_REGEX

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

Public Instance Methods

add_parentheses(node, corrector) click to toggle source

rubocop:disable Metrics/AbcSize, Metrics/MethodLength

# File lib/rubocop/cop/util.rb, line 34
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
args_begin(node) click to toggle source

rubocop:enable Metrics/AbcSize, Metrics/MethodLength

# File lib/rubocop/cop/util.rb, line 55
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 67
def args_end(node)
  node.loc.expression.end
end
begins_its_line?(range) click to toggle source
# File lib/rubocop/cop/util.rb, line 80
def begins_its_line?(range)
  range.source_line.index(/\S/) == range.column
end
comment_line?(line_source) click to toggle source

This is a bad API

# File lib/rubocop/cop/util.rb, line 16
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 21
def comment_lines?(node)
  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 102
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 116
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 86
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 151
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 133
def interpret_string_escapes(string)
  StringInterpreter.interpret(string)
end
line(node_or_range) click to toggle source
# File lib/rubocop/cop/util.rb, line 137
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 25
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 112
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 71
def on_node(syms, sexp, excludes = [], &block)
  return to_enum(:on_node, syms, sexp, excludes) unless block

  yield sexp if Array(syms).include?(sexp.type)
  return if Array(excludes).include?(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 29
def parentheses?(node)
  node.loc.respond_to?(:end) && node.loc.end && node.loc.end.is?(')')
end
same_line?(node1, node2) click to toggle source
# File lib/rubocop/cop/util.rb, line 145
def same_line?(node1, node2)
  line1 = line(node1)
  line2 = line(node2)
  line1 && line2 && line1 == line2
end
to_string_literal(string) click to toggle source
# File lib/rubocop/cop/util.rb, line 120
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 155
def to_supported_styles(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 129
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 161
def compatible_external_encoding_for?(src)
  src = src.dup if RUBY_VERSION < '2.3' || RUBY_ENGINE == 'jruby'
  src.force_encoding(Encoding.default_external).valid_encoding?
end