function sourceDecorator()

in content/resources/js/prettify.js [782:891]
85 lines of code
11 McCabe index (conditional complexity)

    function sourceDecorator(options) {
        var shortcutStylePatterns = [], fallthroughStylePatterns = [];
        if (options['tripleQuotedStrings']) {
            // '''multi-line-string''', 'single-line-string', and double-quoted
            shortcutStylePatterns.push(
                [PR_STRING,  /^(?:\'\'\'(?:[^\'\\]|\\[\s\S]|\'{1,2}(?=[^\']))*(?:\'\'\'|$)|\"\"\"(?:[^\"\\]|\\[\s\S]|\"{1,2}(?=[^\"]))*(?:\"\"\"|$)|\'(?:[^\\\']|\\[\s\S])*(?:\'|$)|\"(?:[^\\\"]|\\[\s\S])*(?:\"|$))/,
                    null, '\'"']);
        } else if (options['multiLineStrings']) {
            // 'multi-line-string', "multi-line-string"
            shortcutStylePatterns.push(
                [PR_STRING,  /^(?:\'(?:[^\\\']|\\[\s\S])*(?:\'|$)|\"(?:[^\\\"]|\\[\s\S])*(?:\"|$)|\`(?:[^\\\`]|\\[\s\S])*(?:\`|$))/,
                    null, '\'"`']);
        } else {
            // 'single-line-string', "single-line-string"
            shortcutStylePatterns.push(
                [PR_STRING,
                    /^(?:\'(?:[^\\\'\r\n]|\\.)*(?:\'|$)|\"(?:[^\\\"\r\n]|\\.)*(?:\"|$))/,
                    null, '"\'']);
        }
        if (options['verbatimStrings']) {
            // verbatim-string-literal production from the C# grammar.  See issue 93.
            fallthroughStylePatterns.push(
                [PR_STRING, /^@\"(?:[^\"]|\"\")*(?:\"|$)/, null]);
        }
        var hc = options['hashComments'];
        if (hc) {
            if (options['cStyleComments']) {
                if (hc > 1) {  // multiline hash comments
                    shortcutStylePatterns.push(
                        [PR_COMMENT, /^#(?:##(?:[^#]|#(?!##))*(?:###|$)|.*)/, null, '#']);
                } else {
                    // Stop C preprocessor declarations at an unclosed open comment
                    shortcutStylePatterns.push(
                        [PR_COMMENT, /^#(?:(?:define|elif|else|endif|error|ifdef|include|ifndef|line|pragma|undef|warning)\b|[^\r\n]*)/,
                            null, '#']);
                }
                fallthroughStylePatterns.push(
                    [PR_STRING,
                        /^<(?:(?:(?:\.\.\/)*|\/?)(?:[\w-]+(?:\/[\w-]+)+)?[\w-]+\.h|[a-z]\w*)>/,
                        null]);
            } else {
                shortcutStylePatterns.push([PR_COMMENT, /^#[^\r\n]*/, null, '#']);
            }
        }
        if (options['cStyleComments']) {
            fallthroughStylePatterns.push([PR_COMMENT, /^\/\/[^\r\n]*/, null]);
            fallthroughStylePatterns.push(
                [PR_COMMENT, /^\/\*[\s\S]*?(?:\*\/|$)/, null]);
        }
        if (options['regexLiterals']) {
            /**
             * @const
             */
            var REGEX_LITERAL = (
                // A regular expression literal starts with a slash that is
                // not followed by * or / so that it is not confused with
                // comments.
                '/(?=[^/*])'
                    // and then contains any number of raw characters,
                    + '(?:[^/\\x5B\\x5C]'
                    // escape sequences (\x5C),
                    +    '|\\x5C[\\s\\S]'
                    // or non-nesting character sets (\x5B\x5D);
                    +    '|\\x5B(?:[^\\x5C\\x5D]|\\x5C[\\s\\S])*(?:\\x5D|$))+'
                    // finally closed by a /.
                    + '/');
            fallthroughStylePatterns.push(
                ['lang-regex',
                    new RegExp('^' + REGEXP_PRECEDER_PATTERN + '(' + REGEX_LITERAL + ')')
                ]);
        }

        var types = options['types'];
        if (types) {
            fallthroughStylePatterns.push([PR_TYPE, types]);
        }

        var keywords = ("" + options['keywords']).replace(/^ | $/g, '');
        if (keywords.length) {
            fallthroughStylePatterns.push(
                [PR_KEYWORD,
                    new RegExp('^(?:' + keywords.replace(/[\s,]+/g, '|') + ')\\b'),
                    null]);
        }

        shortcutStylePatterns.push([PR_PLAIN,       /^\s+/, null, ' \r\n\t\xA0']);
        fallthroughStylePatterns.push(
            // TODO(mikesamuel): recognize non-latin letters and numerals in idents
            [PR_LITERAL,     /^@[a-z_$][a-z_$@0-9]*/i, null],
            [PR_TYPE,        /^(?:[@_]?[A-Z]+[a-z][A-Za-z_$@0-9]*|\w+_t\b)/, null],
            [PR_PLAIN,       /^[a-z_$][a-z_$@0-9]*/i, null],
            [PR_LITERAL,
                new RegExp(
                    '^(?:'
                        // A hex number
                        + '0x[a-f0-9]+'
                        // or an octal or decimal number,
                        + '|(?:\\d(?:_\\d+)*\\d*(?:\\.\\d*)?|\\.\\d\\+)'
                        // possibly in scientific notation
                        + '(?:e[+\\-]?\\d+)?'
                        + ')'
                        // with an optional modifier like UL for unsigned long
                        + '[a-z]*', 'i'),
                null, '0123456789'],
            // Don't treat escaped quotes in bash as starting strings.  See issue 144.
            [PR_PLAIN,       /^\\[\s\S]?/, null],
            [PR_PUNCTUATION, /^.[^\s\w\.$@\'\"\`\/\#\\]*/, null]);

        return createSimpleLexer(shortcutStylePatterns, fallthroughStylePatterns);
    }