[0.17.52] Damaged rail tracks prevent robots from placing curved segments

[newllama]

Steps to reproduce:
- Place some train tracks
- Turn off personal roboport and damage a single straight segment with 'C' key (damage, not destroy)
- Deconstruct the tracks
- At this point your inventory should contain 1 damaged rail track
- Place a curved track ghost

What happens:
A construction robot takes the damaged track from the player's inventory and then can't figure out what to do

What should happen:
The robot should know that it doesn't have enough damaged tracks to make a damaged curved rail.

Video:
https://gfycat.com/obesepitifulgalago

[Rseding91]

Thanks for the report. I don't consider this scenario worth the code complication and bugs it will introduce to try to account for it when building by robots.

You'll simply have to repair the rail before the robots try to use it.

[DaveMcW]

Why not allow the track to be built, and set its health to the average of the rails?

[newllama]

Thanks for the report. I don't consider this scenario worth the code complication and bugs it will introduce to try to account for it when building by robots.

You'll simply have to repair the rail before the robots try to use it.

I'd like to point out one additional thing.. The bots seem to actually *prioritize* using damaged tracks over normal tracks. The effect is that if you have a number of damaged track pieces which isn't divisible by 4 then your inventory is "poisoned" and the bots will misbehave. This isn't a just a rare issue that will only happen if you have a small number of tracks.

As a developer myself I know that strangers speculating about changes to code that they've never seen is just about the most annoying thing ever BUT it seems like it shouldn't be too hard to make the bot not consider the job under these conditions. The fact that it takes the track out of the player's inventory and then follows you forever like a stray dog is just bizarre.