[2.0.72] Bot built trains sometimes do not start automatically

[fall guy]

sometimes when blueprinting trains and allowing construction bots to build them uninterrupted the train will remain in manual mode instead of entering automatic. this is rare but seems most common when printing a train on curved track. a save file has been provided, when pasting the blueprint with the 2 1-1 trains near the top of the curved parallel tracks the trains do not enter automatic mode after being fully built.

[Rseding91]

Thanks for the report. This issue seems to be caused by a combination of things:

1. The locomotive and cargo wagon in your blueprint(s) are not actually connected to each other. Likely you had a built locomotive and placed a ghost cargo wagon behind it (this does not physically attach the two). Then when you made the blueprint they are not physically attached and so are not physically attached in the blueprint, or when placed later as ghosts.

2. The locomotive has a fuel request, however because the rolling stock is not physically attached - when the locomotive is built it doesn't see any external ghosts waiting to be built and so marks itself as "train finished building". Then, the fuel requests are set and this fails to re-mark the train as "it's not done being built yet" so when the fuel is finally delivered the train thinks it's already built and doesn't switch to automatic.

I've fixed #2 for the next release which addresses that specific case - however because of how you've made the blueprint if the locomotive was built first, and fuel delivered - it would drive away without waiting for the cargo wagon to be built.