Module: Kramdown::Converter::SyntaxHighlighter::Rouge

Defined in:
lib/kramdown/converter/syntax_highlighter/rouge.rb

Overview

Uses Rouge which is CSS-compatible to Pygments to highlight code blocks and code spans.

Class Method Summary collapse

Class Method Details

.call(converter, text, lang, type, call_opts) ⇒ Object 



24
25
26
27
28
29
30
31
32
33
34
35
 
# File 'lib/kramdown/converter/syntax_highlighter/rouge.rb', line 24

def self.call(converter, text, lang, type, call_opts)
  opts = options(converter, type)
  call_opts[:default_lang] = opts[:default_lang]
  return nil unless lang || opts[:default_lang] || opts[:guess_lang]

  lexer = ::Rouge::Lexer.find_fancy(lang || opts[:default_lang], text)
  return nil if opts[:disable] || !lexer || (lexer.tag == "plaintext" && !opts[:guess_lang])

  opts[:css_class] ||= 'highlight' # For backward compatibility when using Rouge 2.0
  formatter = formatter_class(opts).new(opts)
  formatter.format(lexer.lex(text))
end

.formatter_class(opts = {}) ⇒ Object 



68
69
70
71
72
73
74
75
76
77
78
79
80
81
 
# File 'lib/kramdown/converter/syntax_highlighter/rouge.rb', line 68

def self.formatter_class(opts = {})
  case formatter = opts[:formatter]
  when Class
    formatter
  when /\A[[:upper:]][[:alnum:]_]*\z/
    ::Rouge::Formatters.const_get(formatter, false)
  else
    # Available in Rouge 2.0 or later
    ::Rouge::Formatters::HTMLLegacy
  end
rescue NameError
  # Fallback to Rouge 1.x
  ::Rouge::Formatters::HTML
end

.normalize_keys(hash) ⇒ Object 



60
61
62
63
64
65
66
 
# File 'lib/kramdown/converter/syntax_highlighter/rouge.rb', line 60

def self.normalize_keys(hash)
  return if hash.empty?

  hash.keys.each do |k|
    hash[k.kind_of?(String) ? Kramdown::Options.str_to_sym(k) : k] = hash.delete(k)
  end
end

.options(converter, type) ⇒ Object 



37
38
39
40
 
# File 'lib/kramdown/converter/syntax_highlighter/rouge.rb', line 37

def self.options(converter, type)
  prepare_options(converter)
  converter.data[:syntax_highlighter_rouge][type]
end

.prepare_options(converter) ⇒ Object 



42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
 
# File 'lib/kramdown/converter/syntax_highlighter/rouge.rb', line 42

def self.prepare_options(converter)
  return if converter.data.key?(:syntax_highlighter_rouge)

  cache = converter.data[:syntax_highlighter_rouge] = {}

  opts = converter.options[:syntax_highlighter_opts].dup

  span_opts = opts.delete(:span)&.dup || {}
  block_opts = opts.delete(:block)&.dup || {}
  normalize_keys(span_opts)
  normalize_keys(block_opts)

  cache[:span] = opts.merge(span_opts)
  cache[:span][:wrap] = false

  cache[:block] = opts.merge(block_opts)
end