marionebl/jogwheel

var util = require('gulp-util');

module.exports = function (gulp) {
    return function list() {
        /* @desc list all public tasks */
        var tasks = Object.keys(gulp.tasks || {})
            .reduce(function (results, taskName) {
                var task = gulp.tasks[taskName];
                var match = String(task.fn).match(/\/\*\s@desc\s(.*)?\s\*\//);

                return results.concat({
                    name: task.name,
                    description: match ? match[1] : '',
                    fn: task.fn
                });
            }, []);

        var length = tasks.map(function (task) {
            return task.name.length;
        }).sort(function (a, b) {
            return b - a;
        })[0];

        var format = util.colors.cyan.bold;

        util.log('');
        util.log(util.colors.bold('Tasks'));

        tasks.forEach(function (task) {
            var aliases = tasks
                .filter(function (alias) {
                    return alias !== task && alias.fn === task.fn;
                })
                .map(function (alias) {
                    return alias.name;
                });

            var aliasList = aliases.length ? 'also: [' + aliases.join(', ') + ']' : '';
            var spacing = new Array(length + 4 - task.name.length).join(' ');
            util.log(`    ${format(task.name)}${spacing}– ${task.description} ${util.colors.bold.grey(aliasList)}`);
        });
        util.log('');
    };
};