index.js

function highlightPug(hljs) {

  var TAG_SELECTORS = 'abbr|acronym|address|area|article|aside|audio|base|big|blockquote|body|br|button|canvas|caption|cite|code|col|colgroup|command|datalist|dd|del|details|dfn|div|dl|dt|em|embed|fieldset|figcaption|figure|footer|form|frame|frameset|(h[1-6])|head|header|hgroup|hr|html|i|iframe|img|ins|kbd|keygen|label|legend|li|link|map|mark|meta|meter|nav|noframes|noscript|object|ol|optgroup|option|output|p|param|pre|progress|q|rp|rt|ruby|samp|script|section|select|small|span|strike|strong|style|sub|sup|table|tbody|td|textarea|tfoot|th|thead|time|title|tr|tt|ul|var|video|a|input';

  return {
    case_insensitive: false,
    aliases: ['jade'],
    keywords: {
      keyword: 'define if else unless each for in elseif var const let while do import include block extends switch case when default break continue until append prepend'
    },
    contains: [
      // string
      {
        className: 'string',
        begin: '`', end: '`',
        illegal: '\\n',
        contains: [hljs.BACKSLASH_ESCAPE]
      },
      // doctype
      {
        className: 'comment',
        begin: 'doctype.*',
        relevance: 0
      },
      // variable
      {
        className: 'variable',
        relevance: 0,
        variants: [
          {
            begin: '\\#{', end: '\\}', excludeBegin: true, excludeEnd: true
          },
          {
            begin: '\\${', end: '\\}', excludeBegin: true, excludeEnd: true
          }
        ]
      },
      // comment
      {
        className: 'comment',
        begin: /\/\/-?.*/
      },
      // tag
      {
        className: 'selector-tag',
        begin: '\\b(' + TAG_SELECTORS + ')\\b'
      },
      // id
      {
        className: 'selector-id', begin: /#[A-Za-z0-9_-]+/
      },
      // class
      {
        className: 'type', begin: /\.[A-Za-z0-9_-]+/
      },
      // attributes
      {
        className: 'attribute',
        begin: '&attributes',
        relevance: 0
      },
      // symbol
      {
        className: 'symbol',
        begin: /[=,:?!]|\.($|\n)/
      }
    ]
  };
}

module.exports = highlightPug;