source: node_modules/prismjs/components/prism-twig.js

Prism.languages.twig = {
        'comment': /^\{#[\s\S]*?#\}$/,

        'tag-name': {
                pattern: /(^\{%-?\s*)\w+/,
                lookbehind: true,
                alias: 'keyword'
        },
        'delimiter': {
                pattern: /^\{[{%]-?|-?[%}]\}$/,
                alias: 'punctuation'
        },

        'string': {
                pattern: /("|')(?:\\.|(?!\1)[^\\\r\n])*\1/,
                inside: {
                        'punctuation': /^['"]|['"]$/
                }
        },
        'keyword': /\b(?:even|if|odd)\b/,
        'boolean': /\b(?:false|null|true)\b/,
        'number': /\b0x[\dA-Fa-f]+|(?:\b\d+(?:\.\d*)?|\B\.\d+)(?:[Ee][-+]?\d+)?/,
        'operator': [
                {
                        pattern: /(\s)(?:and|b-and|b-or|b-xor|ends with|in|is|matches|not|or|same as|starts with)(?=\s)/,
                        lookbehind: true
                },
                /[=<>]=?|!=|\*\*?|\/\/?|\?:?|[-+~%|]/
        ],
        'punctuation': /[()\[\]{}:.,]/
};

Prism.hooks.add('before-tokenize', function (env) {
        if (env.language !== 'twig') {
                return;
        }

        var pattern = /\{(?:#[\s\S]*?#|%[\s\S]*?%|\{[\s\S]*?\})\}/g;
        Prism.languages['markup-templating'].buildPlaceholders(env, 'twig', pattern);
});

Prism.hooks.add('after-tokenize', function (env) {
        Prism.languages['markup-templating'].tokenizePlaceholders(env, 'twig');
});