Struct SnapshotFoldProvider 

pub struct SnapshotFoldProvider { /* private fields */ }

Owned-snapshot FoldProvider adapter. Carries a copy of the buffer’s fold list (one Vec<Fold> clone — fold lists are tiny in practice) plus the buffer’s row_count, so the call site can hold the snapshot for fold queries while passing &mut hjkl_buffer::View to a motion function that needs cursor mutation.

Introduced in 0.0.40 (Patch C-δ.5) so the lifted motion fns can take &dyn FoldProvider separately from &mut B: Cursor + Query without the call site running into the immutable-vs-mutable borrow conflict that arises with BufferFoldProvider / BufferFoldProviderMut (both of which hold a buffer borrow).

The snapshot is read-only — apply and invalidate_range are no-ops (any fold mutation must go through the canonical BufferFoldProviderMut adapter against the live buffer).

Implementations

impl SnapshotFoldProvider

pub fn from_buffer(buffer: &RopeBuffer) -> Self

Snapshot the current fold list + row-count from buffer. The snapshot is decoupled from the buffer’s lifetime, so the caller can immediately re-borrow the buffer mutably.

Trait Implementations

impl FoldProvider for SnapshotFoldProvider

fn next_visible_row(&self, row: usize, _row_count: usize) -> Option<usize>

First visible row strictly after row, skipping hidden rows. None past the end of the buffer.

fn prev_visible_row(&self, row: usize) -> Option<usize>

First visible row strictly before row. None past the top.

fn is_row_hidden(&self, row: usize) -> bool

Is row currently hidden by a closed fold?

fn fold_at_row(&self, row: usize) -> Option<(usize, usize, bool)>

Range (start_row, end_row, closed) of the fold containing row, if any. Lets za / zo / zc find their target without iterating the full fold list.

fn apply(&mut self, op: FoldOp)

Apply a FoldOp to the underlying fold storage. Read-only providers (e.g. crate::buffer_impl::BufferFoldProvider which holds a &View) and providers that don’t track folds (e.g. NoopFoldProvider) implement this as a no-op.

fn invalidate_range(&mut self, start_row: usize, end_row: usize)

Drop every fold whose range overlaps [start_row, end_row]. Edit pipelines call this after a user edit so vim’s “edits inside a fold open it” behaviour fires. Default impl forwards to FoldProvider::apply with a FoldOp::Invalidate.