1 //! This module defines Concrete Syntax Tree (CST), used by rust-analyzer.
3 //! The CST includes comments and whitespace, provides a single node type,
4 //! `SyntaxNode`, and a basic traversal API (parent, children, siblings).
6 //! The *real* implementation is in the (language-agnostic) `rowan` crate, this
7 //! module just wraps its API.
9 use rowan::{GreenNodeBuilder, Language};
11 use crate::{Parse, SmolStr, SyntaxError, SyntaxKind, TextSize};
13 pub(crate) use rowan::{GreenNode, GreenToken};
15 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
16 pub enum RustLanguage {}
17 impl Language for RustLanguage {
18 type Kind = SyntaxKind;
20 fn kind_from_raw(raw: rowan::SyntaxKind) -> SyntaxKind {
21 SyntaxKind::from(raw.0)
24 fn kind_to_raw(kind: SyntaxKind) -> rowan::SyntaxKind {
25 rowan::SyntaxKind(kind.into())
29 pub type SyntaxNode = rowan::SyntaxNode<RustLanguage>;
30 pub type SyntaxToken = rowan::SyntaxToken<RustLanguage>;
31 pub type SyntaxElement = rowan::SyntaxElement<RustLanguage>;
32 pub type SyntaxNodeChildren = rowan::SyntaxNodeChildren<RustLanguage>;
33 pub type SyntaxElementChildren = rowan::SyntaxElementChildren<RustLanguage>;
35 pub use rowan::{Direction, NodeOrToken};
38 pub struct SyntaxTreeBuilder {
39 errors: Vec<SyntaxError>,
40 inner: GreenNodeBuilder<'static>,
43 impl SyntaxTreeBuilder {
44 pub(crate) fn finish_raw(self) -> (GreenNode, Vec<SyntaxError>) {
45 let green = self.inner.finish();
49 pub fn finish(self) -> Parse<SyntaxNode> {
50 let (green, errors) = self.finish_raw();
51 if cfg!(debug_assertions) {
52 let node = SyntaxNode::new_root(green.clone());
53 crate::validation::validate_block_structure(&node);
55 Parse::new(green, errors)
58 pub fn token(&mut self, kind: SyntaxKind, text: SmolStr) {
59 let kind = RustLanguage::kind_to_raw(kind);
60 self.inner.token(kind, text)
63 pub fn start_node(&mut self, kind: SyntaxKind) {
64 let kind = RustLanguage::kind_to_raw(kind);
65 self.inner.start_node(kind)
68 pub fn finish_node(&mut self) {
69 self.inner.finish_node()
72 pub fn error(&mut self, error: ra_parser::ParseError, text_pos: TextSize) {
73 self.errors.push(SyntaxError::new_at_offset(*error.0, text_pos))