| module Jekyll |
| module Tags |
| class HighlightBlock < Liquid::Block |
| include Liquid::StandardFilters |
| |
| # The regular expression syntax checker. Start with the language specifier. |
| # Follow that by zero or more space separated options that take one of three |
| # forms: name, name=value, or name="<quoted list>" |
| # |
| # <quoted list> is a space-separated list of numbers |
| SYNTAX = %r!^([a-zA-Z0-9.+#_-]+)((\s+\w+(=(\w+|"([0-9]+\s)*[0-9]+"))?)*)$! |
| |
| def initialize(tag_name, markup, tokens) |
| super |
| if markup.strip =~ SYNTAX |
| @lang = Regexp.last_match(1).downcase |
| @highlight_options = parse_options(Regexp.last_match(2)) |
| else |
| raise SyntaxError, <<-eos |
| Syntax Error in tag 'highlight' while parsing the following markup: |
| |
| #{markup} |
| |
| Valid syntax: highlight <lang> [linenos] |
| eos |
| end |
| end |
| |
| def render(context) |
| prefix = context["highlighter_prefix"] || "" |
| suffix = context["highlighter_suffix"] || "" |
| code = super.to_s.gsub(%r!\A(\n|\r)+|(\n|\r)+\z!, "") |
| |
| is_safe = !!context.registers[:site].safe |
| |
| output = |
| case context.registers[:site].highlighter |
| when "pygments" |
| render_pygments(code, is_safe) |
| when "rouge" |
| render_rouge(code) |
| else |
| render_codehighlighter(code) |
| end |
| |
| rendered_output = add_code_tag(output) |
| prefix + rendered_output + suffix |
| end |
| |
| def sanitized_opts(opts, is_safe) |
| if is_safe |
| Hash[[ |
| [:startinline, opts.fetch(:startinline, nil)], |
| [:hl_lines, opts.fetch(:hl_lines, nil)], |
| [:linenos, opts.fetch(:linenos, nil)], |
| [:encoding, opts.fetch(:encoding, "utf-8")], |
| [:cssclass, opts.fetch(:cssclass, nil)], |
| ].reject { |f| f.last.nil? }] |
| else |
| opts |
| end |
| end |
| |
| private |
| |
| def parse_options(input) |
| options = {} |
| unless input.empty? |
| # Split along 3 possible forms -- key="<quoted list>", key=value, or key |
| input.scan(%r!(?:\w="[^"]*"|\w=\w|\w)+!) do |opt| |
| key, value = opt.split("=") |
| # If a quoted list, convert to array |
| if value && value.include?("\"") |
| value.delete!('"') |
| value = value.split |
| end |
| options[key.to_sym] = value || true |
| end |
| end |
| if options.key?(:linenos) && options[:linenos] == true |
| options[:linenos] = "inline" |
| end |
| options |
| end |
| |
| def render_pygments(code, is_safe) |
| Jekyll::External.require_with_graceful_fail("pygments") |
| |
| highlighted_code = Pygments.highlight( |
| code, |
| :lexer => @lang, |
| :options => sanitized_opts(@highlight_options, is_safe) |
| ) |
| |
| if highlighted_code.nil? |
| Jekyll.logger.error <<eos |
| There was an error highlighting your code: |
| |
| #{code} |
| |
| While attempting to convert the above code, Pygments.rb returned an unacceptable value. |
| This is usually a timeout problem solved by running `jekyll build` again. |
| eos |
| raise ArgumentError, "Pygments.rb returned an unacceptable value "\ |
| "when attempting to highlight some code." |
| end |
| |
| highlighted_code.sub('<div class="highlight"><pre>', "").sub("</pre></div>", "") |
| end |
| |
| def render_rouge(code) |
| Jekyll::External.require_with_graceful_fail("rouge") |
| formatter = Rouge::Formatters::HTML.new( |
| :line_numbers => @highlight_options[:linenos], |
| :wrap => false |
| ) |
| lexer = Rouge::Lexer.find_fancy(@lang, code) || Rouge::Lexers::PlainText |
| formatter.format(lexer.lex(code)) |
| end |
| |
| def render_codehighlighter(code) |
| h(code).strip |
| end |
| |
| def add_code_tag(code) |
| code_attributes = [ |
| "class=\"language-#{@lang.to_s.tr("+", "-")}\"", |
| "data-lang=\"#{@lang}\"", |
| ].join(" ") |
| "<figure class=\"highlight\"><pre><code #{code_attributes}>"\ |
| "#{code.chomp}</code></pre></figure>" |
| end |
| end |
| end |
| end |
| |
| Liquid::Template.register_tag("highlight", Jekyll::Tags::HighlightBlock) |