Function contents 

pub fn contents(
    ids: &[String],
    catalog: &Catalog,
    platform: &LinuxInfo,
    complete: bool,
    system: &dyn System,
    scratch: &Path,
) -> Result<Contents, BundleError>

Which entries can go offline, and the packages they need. complete takes every dependency; otherwise those this machine lacks, which suits a machine set up like this one. scratch is a folder for pacman’s empty database.