Function dochy_fs::history::set_current_root_obj_info

pub fn set_current_root_obj_info(
    history_info: &HistoryInfo, 
    current_root_obj_info: Option<CurrentRootObjInfo>
)

During save and load, the RootObject’s ID and the selected file is recorded. If you use the same RootObject in the next save, the file to be derived is automatically selected by the system.

This is the backdoor. You can set the ID and file info and designate the file to be derived in the next save. Arbitrary deriving is not supported. You must derive from an older state of the RootObject.

Calling this function before the MutexGuard is dropped results deadlock.