Grunt task to replace file names for require-statements with shorter names, reducing final file size slighty.

grunt_task_shortify_require_js.js

    /**
     *  Grunt task to replace file names for require-statements with shorter names
     *  reducing final file size slighty.
     * 
     *  (C) 2016 mattias@allbinary, All Binary AB
     * 
     *  Example configuration:
     *         shortify_js: {
     *      build: {
     *          options: {
     *              prefix: '' // use a prefix for filenames
     *          },
     *          files: [
     *              {expand: true, cwd: 'build/js/', src: 'app.js', dest: './'},
     *          ]
     *      }
     *  }
     */
    grunt.registerMultiTask('shortify_js', function() {

        var pfx = this.data && this.data.options ? this.data.options.prefix || '' : '';
        function shortify(str) {
            var requires = {};
            var nn = 0;
            var chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
            function allocName() {
                return pfx + (chars[ ((nn++)%chars.length) ] + (nn > chars.length ? (Math.floor(nn/chars.length)) : ''));
            }

            str.replace(/require\(([^\)]*)/g, function(a,b) {
                b = b.replace(/['"]/g, ''); // un-quote
                if(typeof requires[b] === 'undefined') {
                    requires[b] = allocName();
                }
            });

            var keys = Object.keys(requires);

            keys.filter(function(r) {
                // require('xyz');
                var re1 = new RegExp("require\\('"+r+"'", 'g');
                str = str.replace(re1, "require('"+requires[r]+"'");
                // require("xyz");
                var re2 = new RegExp('require\\("'+r+'"', 'g');
                str = str.replace(re2, 'require("'+requires[r]+'"');
                // "xyz":<num>
                var re3 = new RegExp('"'+r+'":([0-9]*)', 'g');
                str = str.replace(re3, '"'+requires[r]+'":$1');
            });
            return str;
        }


        var files = this.files;

        for(var i=0; i < files.length; i++) {
            var file = files[i];
            var content = grunt.file.read(file.src[0], { encoding: null }).toString();
            var len1 = content.length;
            var res = shortify(content);
            grunt.file.write(file.dest, res.content);
            var saved = len1 - res.length;
            grunt.log.writeln('wrote ' + file.dest + ' from ' + file.src[0] + ', saving ' + saved + ' bytes');
        }

    });