The student pilot was taking his private pilot checkride and was performing a soft-field takeoff from a touch-and-go. The student pilot reported that immediately after the takeoff, the airplane experienced “windshear" from the right and the airplane banked left and drifted left of centerline. He corrected with right aileron, which at first had no effect, then the airplane rapidly banked right and the right-wing tip struck the runway surface. The airplane then banked and yawed left and pitched up. The airplane descended from about 15 ft in a nose low left wing down attitude and impacted the runway surface hard. The designated pilot examiner (DPE) stated that the student pilot performed a good soft field landing and then after the soft-field takeoff, the right wing suddenly dipped, and the wingtip struck the runway. As the DPE was about to say "abort," the airplane pitched up and rolled left. The DPE then got on the controls with the student pilot and they both had full right aileron applied, but the airplane did not respond and subsequently impacted the runway. The fuselage and wings were substantially damaged. The student pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.