Struct HeaderGroupFoldProvider 

pub struct HeaderGroupFoldProvider { /* private fields */ }

AF.1: one open [lattice_core::Fold] per header run — the rows a user sees under one header.

The grouping rule handles both header conventions in the tree with one pass, which is what lets this be a shared mechanism rather than an agenda-shaped special case:

• a non-empty title that differs from the current group’s starts a new group (search’s per-excerpt file headers; the agenda’s run labels);
• a non-empty title equal to the current group’s continues it (search’s second and later excerpts from one file);
• an empty title continues the current group (the agenda’s rows after the first of a run — an empty title renders no header row, which is exactly what “I belong to the group above” means).

identity is the group’s TITLE, so the closed/open state survives a gr refresh — recompute_folds carries state by matching identity, and the title is what the user was collapsing. That is the same reasoning PD.5a applied to paths for FileBoundaryFoldProvider, and it holds here for the same reason: the hit-count badge lives in its own field rather than in title, so a refresh that changes the count does not change the identity.

Implementations

impl HeaderGroupFoldProvider

pub fn new(handle: MultibufferDocumentHandle, buffer_id: BufferId) -> Self

Trait Implementations

impl FoldSource for HeaderGroupFoldProvider

fn id(&self) -> ProviderId

This source’s stable id: the same on every call, and distinct from every other registered source’s (see [ProviderId]).

fn compute_folds(&self) -> Vec<Fold>

Produce the current fold ranges. Called by the host on recompute, so it should be cheap (read already-computed state; no I/O).