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 //! modules just wraps its API.
9 use ra_parser::ParseError;
10 use rowan::{GreenNodeBuilder, Language};
13 syntax_error::{SyntaxError, SyntaxErrorKind},
14 Parse, SmolStr, SyntaxKind, TextUnit,
17 pub(crate) use rowan::{GreenNode, GreenToken};
19 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
20 pub enum RustLanguage {}
21 impl Language for RustLanguage {
22 type Kind = SyntaxKind;
24 fn kind_from_raw(raw: rowan::cursor::SyntaxKind) -> SyntaxKind {
25 SyntaxKind::from(raw.0)
28 fn kind_to_raw(kind: SyntaxKind) -> rowan::cursor::SyntaxKind {
29 rowan::cursor::SyntaxKind(kind.into())
33 pub type SyntaxNode = rowan::SyntaxNode<RustLanguage>;
34 pub type SyntaxToken = rowan::SyntaxToken<RustLanguage>;
35 pub type SyntaxElement = rowan::NodeOrToken<SyntaxNode, SyntaxToken>;
36 pub type SyntaxNodeChildren = rowan::SyntaxNodeChildren<RustLanguage>;
37 pub type SyntaxElementChildren = rowan::SyntaxElementChildren<RustLanguage>;
39 pub use rowan::{Direction, NodeOrToken};
41 pub struct SyntaxTreeBuilder {
42 errors: Vec<SyntaxError>,
43 inner: GreenNodeBuilder<'static>,
46 impl Default for SyntaxTreeBuilder {
47 fn default() -> SyntaxTreeBuilder {
48 SyntaxTreeBuilder { errors: Vec::new(), inner: GreenNodeBuilder::new() }
52 impl SyntaxTreeBuilder {
53 pub(crate) fn finish_raw(self) -> (GreenNode, Vec<SyntaxError>) {
54 let green = self.inner.finish();
58 pub fn finish(self) -> Parse<SyntaxNode> {
59 let (green, errors) = self.finish_raw();
60 let node = SyntaxNode::new_root(green);
61 if cfg!(debug_assertions) {
62 crate::validation::validate_block_structure(&node);
64 Parse::new(node.green().clone(), errors)
67 pub fn token(&mut self, kind: SyntaxKind, text: SmolStr) {
68 let kind = RustLanguage::kind_to_raw(kind);
69 self.inner.token(kind, text)
72 pub fn start_node(&mut self, kind: SyntaxKind) {
73 let kind = RustLanguage::kind_to_raw(kind);
74 self.inner.start_node(kind)
77 pub fn finish_node(&mut self) {
78 self.inner.finish_node()
81 pub fn error(&mut self, error: ParseError, text_pos: TextUnit) {
82 let error = SyntaxError::new(SyntaxErrorKind::ParseError(error), text_pos);
83 self.errors.push(error)