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, SyntaxError, SyntaxKind, TextSize};
13 pub(crate) use rowan::{GreenNode, GreenToken, NodeOrToken};
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>;
36 pub struct SyntaxTreeBuilder {
37 errors: Vec<SyntaxError>,
38 inner: GreenNodeBuilder<'static>,
41 impl SyntaxTreeBuilder {
42 pub(crate) fn finish_raw(self) -> (GreenNode, Vec<SyntaxError>) {
43 let green = self.inner.finish();
47 pub fn finish(self) -> Parse<SyntaxNode> {
48 let (green, errors) = self.finish_raw();
49 if cfg!(debug_assertions) {
50 let node = SyntaxNode::new_root(green.clone());
51 crate::validation::validate_block_structure(&node);
53 Parse::new(green, errors)
56 pub fn token(&mut self, kind: SyntaxKind, text: &str) {
57 let kind = RustLanguage::kind_to_raw(kind);
58 self.inner.token(kind, text)
61 pub fn start_node(&mut self, kind: SyntaxKind) {
62 let kind = RustLanguage::kind_to_raw(kind);
63 self.inner.start_node(kind)
66 pub fn finish_node(&mut self) {
67 self.inner.finish_node()
70 pub fn error(&mut self, error: parser::ParseError, text_pos: TextSize) {
71 self.errors.push(SyntaxError::new_at_offset(*error.0, text_pos))