While using repair turrets (awesome mod by the way) I got an error that crashed my game. I took a screenshot but here is the text of the error. Let me know if there is anything else I can provide. I believe the error was caused by a bunch of construction robots flying into a burning forest and the repair turret trying to repair them while bots took the last of the repair kits from the logistic chest.

Error while running event Repair_Turret::on_tick (ID 0)
_ Repair_Turret /script/repair_turret.lua:279: attempt to index a nil value
stack traceback:
_ Repair_Turret_ /script/repair_turret.lua:279: in function 'get_pickup_entity'
Repair_Turret /script/repair_turret.lua:305: in function 'update_turret'
Repair_Turret /script/repair_turret.lua:424 in function 'handler'
core /lualib/event_handler.lua:44 in function < core _/lualib/event_handler.lua:42>

No idea what caused it, I wasn't paying attention, but same symptom here

Error while running event Repair_Turret::on_tick (ID 0)
Repair_Turret/script/repair_turret.lua:279: attempt to index a nil value
stack traceback:
Repair_Turret/script/repair_turret.lua:279: in function 'get_pickup_entity'
Repair_Turret/script/repair_turret.lua:305: in function 'update_turret'
Repair_Turret/script/repair_turret.lua:424: in function 'handler'
core/lualib/event_handler.lua:44: in function <core/lualib/event_handler.lua:42>

Can you provide a save game?

Ah crap, didnt see this and didnt think to keep a copy of the save, sorry!
It didnt occur again on loading the auto-save though, and hasnt happened since

I just got a similar error today..

Savegame here (lots of enabled mods, sorry for that) -> https://drive.google.com/open?id=18jgcGDPjM2ohYcyGl0Bbte-vO-ICiOlL
To reproduce, simply disable personal roboport in toolbar, then shoot a wall.
Apparently, removing all nearby roboports prevents the crash

Error while running event Repair_Turret::on_tick (ID 0)
Repair_Turret/script/repair_turret.lua:279: attempt to index a nil value
stack traceback:
Repair_Turret/script/repair_turret.lua:279: in function 'get_pickup_entity'
Repair_Turret/script/repair_turret.lua:305: in function 'update_turret'
Repair_Turret/script/repair_turret.lua:424: in function 'handler'
core/lualib/event_handler.lua:44: in function <core/lualib/event_handler.lua:42>

Got the same one. Been using this mod for a while now though. Very odd that only just now that the error manifested.