[2.0.20] Bots sometimes remove modules without replacing them

[nthexwn]

What did you do?

I planned several module upgrades using remote view. The modules weren't available at the time. I left the game running overnight.

What happened?

When I came back, several of the machines where upgrades had been planned were missing modules entirely.

What did you expect to happen instead? It might be obvious to you, but do it anyway!

I expected that robots wouldn't remove the old modules until they could guarantee that they'd be instantly replaced by the new modules which they'd brought to the machines.

Does it happen always, once, or sometimes?

Sometimes.

Repro:

This has already happened, seemingly at random, on dozens of different occasions throughout this playthrough. This time I thought to take a screenshot immediately after planning an upgrade:

Screenshot before failed upgrades

module_upgrade_fail_before.jpg (1.84 MiB) Viewed 348 times

I then took a second screenshot from the same camera position the following day:

Screenshot after failed upgrades

module_upgrade_fail_after.jpg (1.82 MiB) Viewed 348 times

When comparing the screenshots, you can see that several of the beacons where speed module upgrades were planned are now missing their modules.

I've also attached a save game from the time when I took the first screenshot. Simply loading the game and waiting long enough should lead to a reproduction of these same failed upgrades.

Impact:

This issue makes remote module upgrades for large factories very tedious, because the user has to manually inspect every single machine to see if the upgrades failed or not, issue another wave of planned module upgrades, and repeat the process until none of them failed.

Related bugs:

This seems to be a separate issue from the other reported bugs where robots are dropping the replaced modules on the ground. When I use the deconstruction planner filtered to "item on ground" and cover the entire map with it, I don't see any modules anywhere on the ground.

I've also experienced this occurring when upgrading modules on recycling machines. It seems possible that several of the "recycling machine ate my module" bugs are actually experiencing this issue (which applies to all machine types) instead.

[Genhis]

Thanks for the report. Is it possible you could be experiencing something similar to 122101? Could you verify if this is fixed when we release 2.0.22?

[nthexwn]

Thanks for the report. Is it possible you could be experiencing something similar to 122101? Could you verify if this is fixed when we release 2.0.22?

I have several dozen empty logistics storage chests on all of the networks where this has been happening, so I don't think it's related to the bots running out of storage.

[nthexwn]

Could you verify if this is fixed when we release 2.0.22?

I've verified that this bug no longer reproduces on 2.0.23 (stable branch appears to have skipped over 2.0.22). Thanks!