django.js

module.exports = function(hljs) {

  function allowsDjangoSyntax(mode, parent) {
    return (
      parent == undefined || // default mode
      (!mode.className && parent.className == 'tag') || // tag_internal
      mode.className == 'value' // value
    );
  }

  function copy(mode, parent) {
    var result = {};
    for (var key in mode) {
      if (key != 'contains') {
        result[key] = mode[key];
      }
      var contains = [];
      for (var i = 0; mode.contains && i < mode.contains.length; i++) {
        contains.push(copy(mode.contains[i], mode));
      }
      if (allowsDjangoSyntax(mode, parent)) {
        contains = DJANGO_CONTAINS.concat(contains);
      }
      if (contains.length) {
        result.contains = contains;
      }
    }
    return result;
  }

  var FILTER = {
    className: 'filter',
    begin: '\\|[A-Za-z]+\\:?',
    keywords:
      'truncatewords removetags linebreaksbr yesno get_digit timesince random striptags ' +
      'filesizeformat escape linebreaks length_is ljust rjust cut urlize fix_ampersands ' +
      'title floatformat capfirst pprint divisibleby add make_list unordered_list urlencode ' +
      'timeuntil urlizetrunc wordcount stringformat linenumbers slice date dictsort ' +
      'dictsortreversed default_if_none pluralize lower join center default ' +
      'truncatewords_html upper length phone2numeric wordwrap time addslashes slugify first ' +
      'escapejs force_escape iriencode last safe safeseq truncatechars localize unlocalize ' +
      'localtime utc timezone',
    contains: [
      {className: 'argument', begin: '"', end: '"'}
    ]
  };

  var DJANGO_CONTAINS = [
    {
      className: 'template_comment',
      begin: '{%\\s*comment\\s*%}', end: '{%\\s*endcomment\\s*%}'
    },
    {
      className: 'template_comment',
      begin: '{#', end: '#}'
    },
    {
      className: 'template_tag',
      begin: '{%', end: '%}',
      keywords:
        'comment endcomment load templatetag ifchanged endifchanged if endif firstof for ' +
        'endfor in ifnotequal endifnotequal widthratio extends include spaceless ' +
        'endspaceless regroup by as ifequal endifequal ssi now with cycle url filter ' +
        'endfilter debug block endblock else autoescape endautoescape csrf_token empty elif ' +
        'endwith static trans blocktrans endblocktrans get_static_prefix get_media_prefix ' +
        'plural get_current_language language get_available_languages ' +
        'get_current_language_bidi get_language_info get_language_info_list localize ' +
        'endlocalize localtime endlocaltime timezone endtimezone get_current_timezone ' +
        'verbatim',
      contains: [FILTER]
    },
    {
      className: 'variable',
      begin: '{{', end: '}}',
      contains: [FILTER]
    }
  ];

  var result = copy(hljs.LANGUAGES.xml);
  result.case_insensitive = true;
  return result;
};