How to attach time stretch to grid?

I like to stretch a clip to the grid, but I’m not able to. How to do so except trying to enter a clip length manually?

Small video on imgur

Did I miss a tick somewhere or is this impossible?

Maybe I was not clear enough?

If I turn off snapping to grid, I’m not able to precisely set the clips length. So, after some repetitions, it is no longer in sync with the MIDI stuff I do.

If I turn on the grid and snapping, the stretch seem to lock to some grid, but sadly not the bar grid. As you can see in the video, I’m not able to set the length to 2:1:000 because it snaps to something else?