Function cargo::core::registry::summary_for_patch

fn summary_for_patch(
    orig_patch: &Dependency,
    locked: &Option<LockedPatchDependency>,
    summaries: Vec<Summary>,
    source: &mut dyn Source
) -> Poll<CargoResult<(Summary, Option<PackageId>)>>

This is a helper for selecting the summary, or generating a helpful error message.