Tween - Detect elapsed time

Cocos Creator
#1

Is there a way to detect the elapsed time of a tween?

        tween.to(10, { scale: scaleTo }, {
            easing: function (progress) {
                // elapsed time or time passed???
                // duration???
                return progress;
            },
            progress: function (from, to, current, progress) {
                // elapsed time or time passed???
                // duration???
                return progress;
            }
        });

This is really important parameter and I really need it. Currently I am calculating elapsed time from outside the easing function and it is not the best solution for me.