Struct TreeSnapshotResource 

pub struct TreeSnapshotResource { /* private fields */ }

Backing for the tree-snapshot WIT resource: a point-in-time parse tree.

Implementations

impl TreeSnapshotResource

pub fn new(snapshot: Arc<SyntaxSnapshot>) -> Self

Wrap an immutable syntax snapshot as a tree-snapshot backing.

pub fn has_tree(&self) -> bool

Whether the snapshot carries a parse tree. The trampoline mints a resource only when this holds, so every resource method resolves.

pub fn root(&self) -> NodeResource

The tree root.

pub fn language(&self) -> String

The grammar id (e.g. "rust").

pub fn node_at(&self, pos: Position) -> Option<NodeResource>

The smallest NAMED node spanning pos — descend to the smallest node, then walk up to the nearest named ancestor (the root is always named). None when there’s no tree / pos is out of range.

pub fn enclosing(&self, pos: Position, kinds: &[String]) -> Option<NodeResource>

The nearest ancestor of pos (inclusive) whose kind is in kinds — the auto-pair scope query (the native scope_toward precedent). kinds empty → the nearest named ancestor (i.e. node_at). None when no ancestor matches / no tree.

pub fn compile_query(&self, source: &str) -> Result<QueryResource, String>

TS.2: compile a tree-sitter query against this snapshot’s grammar. Err (the tree-sitter message) on a malformed query or a language with no registered grammar.

pub fn run_query( &self, query: &QueryResource, within: Option<NativeRange>, ) -> Vec<(String, NodeResource)>

TS.2: run query over the whole tree (or within a point range), returning the surviving captures — tree-sitter evaluates the #eq? / #match? / #any-of? text predicates against the snapshot’s source (the TextProvider), so only matches that pass cross. Empty when there’s no tree or query was compiled for a different grammar (graceful).

pub fn run_query_ranges( &self, query: &QueryResource, within: Option<NativeRange>, ) -> Vec<(String, u32, NativeRange)>

TS.2b: run_query reduced to extents — same traversal, same host-side predicate filtering, but no NodeResource per capture.

The saving is not the allocation: it is that every returned NodeResource becomes a guest-visible resource-table entry holding its own snapshot bump, which the guest must then drop one at a time across the boundary. A structural query over a large file returns tens of thousands of captures, and that per-capture round trip — not the query itself — is what made whole-file structural queries too slow to run.

The returned u32 is the match ordinal within THIS call, so captures from one pattern match stay groupable (@context with its @context.end) without a containment test on the guest side.