probably.
one day i did this with a vauxhall wedged front first into my lock up. i didn't bother with jump leads, just left it connected, resting on the cam cover.
climbed over the wing, under the bonnet to get out as it was a tight fit. got in the cab and turned the key while peering between bonnet and scuttle to see if the starter worked.
it did. it jumped off the top of the motor and disappeared from view. positive terminal landed on, and cut through the metal petrol pipe, which started squirting petrol 3 ft in the air. this jet of fuel then caught fire
don't panic! so release handbrake, jump back over engine bay, through flames to get to the front of the car and push it out of the lock up. dig out hot starter motor from the geyser of fire by hand and place somewhere safe. put out fire. replace section of wiring loom burnt to feck.
at least i found out the starter motor was ok
since then, i've always removed them from the vehicle and fixed them in the vice before testing. well, mostly i have anyway