Anyone have a door that frustratingly drifts out from the wall when open?
tip; you can remove the center hinge pin, put it on the garage floor w'ever, and use a hammer to tap a slight curve into it. When you re-install it, it will create enough friction to keep a door in w'ever position you place it.
By the opposite way - like a door that is almost pushed too that just opens completely back open on its own?? I assume it will since really you are just trying to get it to stay in the position you want it in...
First thing, check that all the hinge screws are tight. This is the same thing you do if the door starts to rub somewhere.
As Bubba_M stated, the self swinging door is usually due to the casing not being installed plumb in the framing. However, it is usually impossible to tap it into alignment due to all the screws holding it in place. If you can do so, then the door is improperly installed.
To fix the problem generally involves removing the door and trim, removing all but one or two screws on the top/bottom and side that is out of plumb, tapping it into alignment, then replacing everything. Note that there are shims that may need to be replaced. If you don't know how to do all this, buy a book on installing doors.