Struct CellChunk 

pub struct CellChunk {
    pub start_source_line: u32,
    pub rows: Arc<[CellRow]>,
    pub version: MatrixVersion,
}

Contiguous range of matrix rows covering a slice of the buffer.

Invariants (S2 enforces; S1 documents):

• rows is sorted ascending by source_line.
• Folded source lines do not appear; row count is post-fold.
• start_source_line is the FIRST source line that could appear in this chunk’s range. The chunk’s range is [start_source_line, start_source_line + chunk_size) in logical (pre-fold) source-line space. Some of those source lines may be folded and therefore absent from rows.
• version is the MatrixVersion snapshot captured at build time. Cell-builder compares against current RenderState version to decide if this chunk needs rebuild.

Fields

start_source_line: u32

rows: Arc<[CellRow]>

version: MatrixVersion

Implementations

impl CellChunk

pub fn new( start_source_line: u32, rows: impl Into<Arc<[CellRow]>>, version: MatrixVersion, ) -> Self

Construct a chunk. S2 is the production caller.

pub fn empty(start_source_line: u32, version: MatrixVersion) -> Self

Empty chunk anchored at start_source_line. Used when the covered source-line range is entirely folded (no visible rows) or as a placeholder during incremental build.

pub fn row_count(&self) -> u32

Number of matrix rows this chunk contributes (post-fold).

pub fn is_empty(&self) -> bool

true when no rows are present (fully-folded range or freshly-allocated empty chunk).

pub fn row_at_source_line(&self, target: u32) -> Option<&CellRow>

Returns the row whose source_line equals target, if it is present in this chunk (i.e. not folded).

Binary search on source_line; O(log N) for the typical 128-row chunk. Returns None if target is folded or outside the chunk’s range.

pub fn shifted_by(&self, line_delta: i32, new_version: MatrixVersion) -> Self

Clone-with-shifted-line. Produces a new chunk whose start_source_line and every contained row’s source_line are shifted by line_delta. Cell payloads are shared (one Arc refcount bump per row’s cells + inlay_offsets); no rope reads, no theme work, no syntax walk.

Used by the cell-builder’s incremental rebuild path (S2.4.b) for chunks past a single-line edit’s affected range — their cell content is unchanged, only their logical line position shifts. new_version stamps the chunk with the publisher’s current matrix version so the renderer can compare against the new matrix’s version.

line_delta may be negative (deletions shift downstream lines down). The shifted source_line saturates at 0 if the caller passes an unreasonably-negative delta; callers in S2.4.b only ever invoke this on chunks past the edit’s affected range, so the saturating path is defensive only.

Trait Implementations

impl Clone for CellChunk

fn clone(&self) -> CellChunk

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CellChunk

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

Formats the value using the given formatter.