pub(super) async fn prepare_call_hierarchy(
environment: &MountainEnvironment,
document_uri: Url,
position_dto: PositionDTO,
) -> Result<Option<Value>, CommonError>Expand description
Prepare call hierarchy - establish the root CallHierarchyItem at the
given document position. Extensions implement prepareCallHierarchy(doc, pos, token). Without this step the incoming/outgoing calls views are always
empty.