Struct ActiveBufferSnapshot 

pub struct ActiveBufferSnapshot<'a> {
    pub buffer_id: u32,
    pub path: Option<&'a Path>,
    pub language: Option<&'a str>,
    pub cursor: Position,
    pub selection: Option<(Position, Position)>,
    pub buffer: &'a Buffer,
    pub syntax_symbols: Vec<(String, u32, u32)>,
    pub syntax_highlights: Vec<Vec<DisplaySpan>>,
}

Snapshot of the active document buffer at the moment the picker opened. Carries enough state for line / mark / outline / grep / LSP-position sources to do their work without a second App round-trip.

Fields

buffer_id: u32

path: Option<&'a Path>

language: Option<&'a str>

Language id ("rust", "markdown", …). Snippet and outline sources filter on this; absent for unknown / untyped buffers.

cursor: Position

selection: Option<(Position, Position)>

Visual-mode selection extent at picker-open, if any. :picker grep defaults its pattern to the selected text when present.

buffer: &'a Buffer

Read-only borrow of the rope. Line / outline / grep sources walk this directly; long-running async work must extract what it needs before init returns.

syntax_symbols: Vec<(String, u32, u32)>

Tree-sitter symbol locations (name, line, byte-col) for the active buffer when syntax is available. Pre-collected by the host via Syntax::collect_symbol_locations; empty when there’s no parser registered for the buffer’s language. Drives :picker outline.

syntax_highlights: Vec<Vec<DisplaySpan>>

PH.2: per-line syntax-highlight spans for the active buffer, one inner Vec per buffer line, each span’s range a line-relative byte range. Pre-collected by the host via SyntaxSnapshot::highlight_lines (a read-only tree query run off the render thread, mirroring the syntax_symbols precedent) and already mapped to DisplaySpan host-side so this crate needs no lattice-cells dependency. Empty when no grammar is registered / the snapshot is stale → plain previews. LinesSource clones the matching line’s spans into a candidate’s display_spans; OutlineSource clips them to the symbol-name column. See docs/dev/architecture/picker-preview-highlight.md §6.