Struct Hunk 

pub struct Hunk {
    pub kind: HunkKind,
    pub ranges: SmallVec<[LineRange; 3]>,
    pub refine: RegionRefinement,
}

A single hunk: a contiguous region of change across the participating documents.

ranges.len() matches the document arity:

• Two-way: [a_range, b_range]
• Three-way: [base_range, local_range, remote_range]

The SmallVec inline capacity of 3 covers both cases without allocation.

Fields

kind: HunkKind

ranges: SmallVec<[LineRange; 3]>

refine: RegionRefinement

DR.4 (2026-08-12): intra-line refinement for this hunk — which BYTES of each changed line actually changed.

Per side, not per pair (DR.5, 2026-08-12). refine.removed is indexed by line - ranges[0].start and refine.added by line - ranges[1].start; the two need not be the same length, which is the whole point — the predecessor shape was pair-keyed and so could not describe an n-removed / m-added hunk at all, making the commonest “rewrite a line and add a comment above it” hunk decline refinement outright.

Empty for a hunk that declined (Add / Remove, identical regions, a wholesale rewrite, or one past the size cap), which renders exactly as it did before refinement existed.

Carried ON the hunk rather than in a parallel map keyed by hunk index, so refinement cannot desynchronise from the ranges it describes — the same “one thing being shifted” property the sign-map derivation relies on. Computed once at diff time, not per render.

Trait Implementations

impl Clone for Hunk

fn clone(&self) -> Hunk

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Hunk

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Hunk

impl PartialEq for Hunk

fn eq(&self, other: &Hunk) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Hunk