CuraEngine from command line fails to accept default_value from non-leaf config json nodes

[richfelker]

Running CuraEngine with the fdmprinter.def.json file from Cura repo is expected to work. However, it errors out with

Trying to retrieve setting with no value given: roofing_layer_count

despite the setting being present in the config json. The root cause seems to be the addition of child config nodes; without them (or with them moved out of it), fetching the value works.

[pepek1910]

I encountered a similar problem with my command-line CuraEngine app. Could you clarify what you mean by 'writing non-leaf'?

[fieldOfView]

By convention, CuraEngine only ever reads leaf settings (ie: settings without children). This is by design. Non-leaf settings can be overridden by more specific ("child") settings.