Had these pop-up in three locations. Only one plant has berries on it, the berry has spines as well. This bunch just flowers and orbs up. Dug it up because I didn't want it to drop seed. Sorry the plant is stressed because I left it in the car, hope it doesn't mislead anyone.
While those berries look a lot like immature Sierra Gooseberries, those flowers and leaves tell me it's probably a tomato relative. Perhaps a Buffalo Bur?