[0.14.22] Roboport sticky circuit bug

[DaveMcW]

In certain circumstances, a circuit network signal from a roboport stays on even after it has been deconstructed.

This save was from a modded game, but I removed all mods and it is still bugged. I could not reproduce it on a new map.

Steps to reproduce
1. Load the save.
2. Run this console command:

code

Code: Select all

/c
script.on_event(defines.events.on_tick, function()
	local pole = game.surfaces[1].find_entities_filtered{name="medium-electric-pole"}[1]
	if (not pole) then return end
	local signal = {name="signal-Z", type="virtual"}
	local red_signal = 0
	local green_signal = 0
	local red_network = pole.get_circuit_network(defines.wire_type.red)
	if red_network then
	  red_signal = red_network.get_signal(signal)
	end
	local green_network = pole.get_circuit_network(defines.wire_type.green)
	if green_network then
	  green_signal = green_network.get_signal(signal)
	end
	game.print("red:" .. red_signal .. " green:"..green_signal)
end)

3. Mine the roboport.

Expected results
red:14 green:14
red:0 green:0

Actual results
red:14 green:14
red:14 green:0
red:0 green:0
The red signal stays on for at least 1 tick even after the roboport is deconstructed.

[Rseding91]

That's expected. Live signals (ones that change every tick) take 1 tick to propagate changes.

[DaveMcW]

Then why does the red signal take 1 tick longer to propagate than the green signal?