Shock Load Testing

I’ve just finished reading the history of RAF Southend during WWII.

There are various references to aircraft suffering damage when their props hit the ground, and having to undergo
“shock load testing”.
I wonder how they did it back then, would it have entailed a full engine strip down ? How else would you know if the
crankshaft was cracked for example ?

How do they do it now ? If an aircraft noses over on landing and the engine comes to a sudden stop, what is the
procedure ? Can you determine what damage may have been done without disassembling the engine ?

I know for instance that on outboard motors, there is a key designed to break if the prop hit something, to save
damaging the motor itself.