module IRB::Color

Constants

ALL

A constant of all-bit 1 to match any Ripper's state in dispatch_seq

BLUE
BOLD
CLEAR
CYAN
GREEN
MAGENTA
RED
REVERSE
TOKEN_KEYWORDS
TOKEN_SEQ_EXPRS

Following pry's colors where possible, but sometimes having a compromise like making backtick and regexp as red (string's color, because they're sharing tokens).

UNDERLINE
YELLOW

Public Class Methods

clear() click to toggle source
# File lib/irb/color.rb, line 95
def clear
  return '' unless colorable?
  "\e[#{CLEAR}m"
end
colorable?() click to toggle source
# File lib/irb/color.rb, line 70
def colorable?
  $stdout.tty? && supported? && (/mswin|mingw/ =~ RUBY_PLATFORM || (ENV.key?('TERM') && ENV['TERM'] != 'dumb'))
end
colorize(text, seq) click to toggle source
# File lib/irb/color.rb, line 100
def colorize(text, seq)
  return text unless colorable?
  seq = seq.map { |s| "\e[#{const_get(s)}m" }.join('')
  "#{seq}#{text}#{clear}"
end
colorize_code(code, complete: true) click to toggle source

If `complete` is false (code is incomplete), this does not warn compile_error. This option is needed to avoid warning a user when the compile_error is happening because the input is not wrong but just incomplete.

# File lib/irb/color.rb, line 109
def colorize_code(code, complete: true)
  return code unless colorable?

  symbol_state = SymbolState.new
  colored = +''
  length = 0

  scan(code, allow_last_error: !complete) do |token, str, expr|
    in_symbol = symbol_state.scan_token(token)
    str.each_line do |line|
      line = Reline::Unicode.escape_for_print(line)
      if seq = dispatch_seq(token, expr, line, in_symbol: in_symbol)
        colored << seq.map { |s| "\e[#{s}m" }.join('')
        colored << line.sub(/\Z/, clear)
      else
        colored << line
      end
    end
    length += str.bytesize
  end

  # give up colorizing incomplete Ripper tokens
  if length != code.bytesize
    return Reline::Unicode.escape_for_print(code)
  end

  colored
end
inspect_colorable?(obj, seen: {}.compare_by_identity) click to toggle source
# File lib/irb/color.rb, line 74
def inspect_colorable?(obj, seen: {}.compare_by_identity)
  case obj
  when String, Symbol, Regexp, Integer, Float, FalseClass, TrueClass, NilClass
    true
  when Hash
    without_circular_ref(obj, seen: seen) do
      obj.all? { |k, v| inspect_colorable?(k, seen: seen) && inspect_colorable?(v, seen: seen) }
    end
  when Array
    without_circular_ref(obj, seen: seen) do
      obj.all? { |o| inspect_colorable?(o, seen: seen) }
    end
  when Range
    inspect_colorable?(obj.begin, seen: seen) && inspect_colorable?(obj.end, seen: seen)
  when Module
    !obj.name.nil?
  else
    false
  end
end

Private Class Methods

dispatch_seq(token, expr, str, in_symbol:) click to toggle source
# File lib/irb/color.rb, line 182
def dispatch_seq(token, expr, str, in_symbol:)
  if token == :on_parse_error or token == :compile_error
    TOKEN_SEQ_EXPRS[token][0]
  elsif in_symbol
    [YELLOW]
  elsif TOKEN_KEYWORDS.fetch(token, []).include?(str)
    [CYAN, BOLD]
  elsif (seq, exprs = TOKEN_SEQ_EXPRS[token]; (expr & (exprs || 0)) != 0)
    seq
  else
    nil
  end
end
scan(code, allow_last_error:) { |event, str, state| ... } click to toggle source
# File lib/irb/color.rb, line 154
def scan(code, allow_last_error:)
  pos = [1, 0]

  lexer = Ripper::Lexer.new(code)
  if lexer.respond_to?(:scan) # Ruby 2.7+
    lexer.scan.each do |elem|
      str = elem.tok
      next if allow_last_error and /meets end of file|unexpected end-of-input/ =~ elem.message
      next if ([elem.pos[0], elem.pos[1] + str.bytesize] <=> pos) <= 0

      str.each_line do |line|
        if line.end_with?("\n")
          pos[0] += 1
          pos[1] = 0
        else
          pos[1] += line.bytesize
        end
      end

      yield(elem.event, str, elem.state)
    end
  else
    lexer.parse.each do |elem|
      yield(elem.event, elem.tok, elem.state)
    end
  end
end
supported?() click to toggle source

Ripper::Lexer::Elem#state is supported on Ruby 2.5+

# File lib/irb/color.rb, line 149
def supported?
  return @supported if defined?(@supported)
  @supported = Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.5.0')
end
without_circular_ref(obj, seen:, &block) click to toggle source
# File lib/irb/color.rb, line 140
def without_circular_ref(obj, seen:, &block)
  return false if seen.key?(obj)
  seen[obj] = true
  block.call
ensure
  seen.delete(obj)
end