Add Twig's spaceless token to twig.js (e.g. `{% spaceless %} ... {% endspaceless %}`)

twig.spaceless.js

Twig.extend(function(Twig) {
    // Add the {% spaceless %} token
    Twig.logic.extend({
        type: 'spaceless',
        regex: /^spaceless$/,
        next: [
            'endspaceless'
        ],
        open: true,

        // Parse the html and return it without any spaces between tags
        parse: function (token, context, chain) {
            var // Parse the output without any filter
                unfiltered = Twig.parse.apply(this, [token.output, context]),
                // A regular expression to find closing and opening tags with spaces between them
                rBetweenTagSpaces = />\s+</g,
                // Replace all space between closing and opening html tags
                output = unfiltered.replace(rBetweenTagSpaces,'><').trim();

            return {
                chain: chain,
                output: output
            };
        }
    });

    // Add the {% endspaceless %} token
    Twig.logic.extend({
        type: 'endspaceless',
        regex: /^endspaceless$/,
        next: [ ],
        open: false
    });
});

This was integrated into twig.js 0.5.6.

twigjs/twig.js#63