Function all_reviewed 

pub fn all_reviewed<'a>(
    hunks: impl IntoIterator<Item = &'a HunkId>,
    reviewed: &HashSet<usize>,
) -> bool

Whether a set of hunks — a group’s, a file’s, a directory’s — reads as done.

Every hunk marked, and at least one hunk to mark: a binary file or a gitlink carries no hunks, and “all of nothing” must not light it up as reviewed. Four rows in the TUI each re-derived that guard by hand.