Steps to reproduce:
- Load any game
- Filter the toolbar so all slots are filtered for raw-wood
- Run this command from the console: game.player.print(tostring(game.player.getinventory(1).caninsert({name = "iron-ore", count = 50})))
- Run this command from the console: game.player.getinventory(1).insert({name = "iron-ore", count = 50})
Note how the "caninsert" returns true but the insert fails (because the toolbelt is filtered). This may also apply to trains (as they can be filtered) but I didn't test them.
EDIT: erp.. meant to go in bug reports. If it could be moved that would be great.