Function plan_pin_edits 

pub(super) fn plan_pin_edits<B: AssetBuilder>(
    root: &RepositoryRoot,
    units: &[Unit],
    versions: &BTreeMap<String, Proposed>,
    builder: &B,
    worktree: &Path,
    edits: &mut PlannedEdits,
) -> Result<(), PinError>

Write the new version and the asset digests into every unit that pins a unit of versions. The assets are built from worktree, which holds the edits of the dependency.