diff --git a/crates/mbe/src/syntax_bridge.rs b/crates/mbe/src/syntax_bridge.rs index 109842b0cd0..39129b03056 100644 --- a/crates/mbe/src/syntax_bridge.rs +++ b/crates/mbe/src/syntax_bridge.rs @@ -1,6 +1,5 @@ //! Conversions between [`SyntaxNode`] and [`tt::TokenTree`]. -use parser::{ParseError, TreeSink}; use rustc_hash::{FxHashMap, FxHashSet}; use syntax::{ ast::{self, make::tokens::doc_comment}, @@ -56,8 +55,18 @@ pub fn token_tree_to_syntax_node( _ => TokenBuffer::from_subtree(tt), }; let parser_tokens = to_parser_tokens(&buffer); + let tree_traversal = parser::parse(&parser_tokens, entry_point); let mut tree_sink = TtTreeSink::new(buffer.begin()); - parser::parse(&parser_tokens, &mut tree_sink, entry_point); + for event in tree_traversal.iter() { + match event { + parser::TraversalStep::Token { kind, n_raw_tokens } => { + tree_sink.token(kind, n_raw_tokens) + } + parser::TraversalStep::EnterNode { kind } => tree_sink.start_node(kind), + parser::TraversalStep::LeaveNode => tree_sink.finish_node(), + parser::TraversalStep::Error { msg } => tree_sink.error(msg.to_string()), + } + } if tree_sink.roots.len() != 1 { return Err(ExpandError::ConversionError); } @@ -643,7 +652,7 @@ fn delim_to_str(d: tt::DelimiterKind, closing: bool) -> &'static str { &texts[idx..texts.len() - (1 - idx)] } -impl<'a> TreeSink for TtTreeSink<'a> { +impl<'a> TtTreeSink<'a> { fn token(&mut self, kind: SyntaxKind, mut n_tokens: u8) { if kind == LIFETIME_IDENT { n_tokens = 2; @@ -741,7 +750,7 @@ impl<'a> TreeSink for TtTreeSink<'a> { *self.roots.last_mut().unwrap() -= 1; } - fn error(&mut self, error: ParseError) { + fn error(&mut self, error: String) { self.inner.error(error, self.text_pos) } } diff --git a/crates/mbe/src/tt_iter.rs b/crates/mbe/src/tt_iter.rs index d05e84b0f02..632b591f65e 100644 --- a/crates/mbe/src/tt_iter.rs +++ b/crates/mbe/src/tt_iter.rs @@ -3,9 +3,8 @@ use crate::{to_parser_tokens::to_parser_tokens, ExpandError, ExpandResult, ParserEntryPoint}; -use parser::TreeSink; use syntax::SyntaxKind; -use tt::buffer::{Cursor, TokenBuffer}; +use tt::buffer::TokenBuffer; macro_rules! err { () => { @@ -94,34 +93,28 @@ impl<'a> TtIter<'a> { &mut self, entry_point: ParserEntryPoint, ) -> ExpandResult> { - struct OffsetTokenSink<'a> { - cursor: Cursor<'a>, - error: bool, - } - - impl<'a> TreeSink for OffsetTokenSink<'a> { - fn token(&mut self, kind: SyntaxKind, mut n_tokens: u8) { - if kind == SyntaxKind::LIFETIME_IDENT { - n_tokens = 2; - } - for _ in 0..n_tokens { - self.cursor = self.cursor.bump_subtree(); - } - } - fn start_node(&mut self, _kind: SyntaxKind) {} - fn finish_node(&mut self) {} - fn error(&mut self, _error: parser::ParseError) { - self.error = true; - } - } - let buffer = TokenBuffer::from_tokens(self.inner.as_slice()); let parser_tokens = to_parser_tokens(&buffer); - let mut sink = OffsetTokenSink { cursor: buffer.begin(), error: false }; + let tree_traversal = parser::parse(&parser_tokens, entry_point); - parser::parse(&parser_tokens, &mut sink, entry_point); + let mut cursor = buffer.begin(); + let mut error = false; + for step in tree_traversal.iter() { + match step { + parser::TraversalStep::Token { kind, mut n_raw_tokens } => { + if kind == SyntaxKind::LIFETIME_IDENT { + n_raw_tokens = 2; + } + for _ in 0..n_raw_tokens { + cursor = cursor.bump_subtree(); + } + } + parser::TraversalStep::EnterNode { .. } | parser::TraversalStep::LeaveNode => (), + parser::TraversalStep::Error { .. } => error = true, + } + } - let mut err = if !sink.cursor.is_root() || sink.error { + let mut err = if !cursor.is_root() || error { Some(err!("expected {:?}", entry_point)) } else { None @@ -130,8 +123,8 @@ impl<'a> TtIter<'a> { let mut curr = buffer.begin(); let mut res = vec![]; - if sink.cursor.is_root() { - while curr != sink.cursor { + if cursor.is_root() { + while curr != cursor { if let Some(token) = curr.token_tree() { res.push(token); } diff --git a/crates/parser/src/event.rs b/crates/parser/src/event.rs index 41b0328027c..ca4c38f2e6c 100644 --- a/crates/parser/src/event.rs +++ b/crates/parser/src/event.rs @@ -10,9 +10,8 @@ use std::mem; use crate::{ - ParseError, + tree_traversal::TreeTraversal, SyntaxKind::{self, *}, - TreeSink, }; /// `Parser` produces a flat list of `Event`s. @@ -77,7 +76,7 @@ pub(crate) enum Event { }, Error { - msg: ParseError, + msg: String, }, } @@ -88,7 +87,8 @@ impl Event { } /// Generate the syntax tree with the control of events. -pub(super) fn process(sink: &mut dyn TreeSink, mut events: Vec) { +pub(super) fn process(mut events: Vec) -> TreeTraversal { + let mut res = TreeTraversal::default(); let mut forward_parents = Vec::new(); for i in 0..events.len() { @@ -117,15 +117,17 @@ pub(super) fn process(sink: &mut dyn TreeSink, mut events: Vec) { for kind in forward_parents.drain(..).rev() { if kind != TOMBSTONE { - sink.start_node(kind); + res.enter_node(kind); } } } - Event::Finish => sink.finish_node(), + Event::Finish => res.leave_node(), Event::Token { kind, n_raw_tokens } => { - sink.token(kind, n_raw_tokens); + res.token(kind, n_raw_tokens); } - Event::Error { msg } => sink.error(msg), + Event::Error { msg } => res.error(msg), } } + + res } diff --git a/crates/parser/src/lib.rs b/crates/parser/src/lib.rs index dc02ae6e83f..67bc7d99065 100644 --- a/crates/parser/src/lib.rs +++ b/crates/parser/src/lib.rs @@ -25,31 +25,19 @@ mod event; mod parser; mod grammar; mod tokens; +mod tree_traversal; #[cfg(test)] mod tests; pub(crate) use token_set::TokenSet; -pub use crate::{lexed_str::LexedStr, syntax_kind::SyntaxKind, tokens::Tokens}; - -#[derive(Debug, Clone, PartialEq, Eq, Hash)] -pub struct ParseError(pub Box); - -/// `TreeSink` abstracts details of a particular syntax tree implementation. -pub trait TreeSink { - /// Adds new token to the current branch. - fn token(&mut self, kind: SyntaxKind, n_tokens: u8); - - /// Start new branch and make it current. - fn start_node(&mut self, kind: SyntaxKind); - - /// Finish current branch and restore previous - /// branch as current. - fn finish_node(&mut self); - - fn error(&mut self, error: ParseError); -} +pub use crate::{ + lexed_str::LexedStr, + syntax_kind::SyntaxKind, + tokens::Tokens, + tree_traversal::{TraversalStep, TreeTraversal}, +}; /// rust-analyzer parser allows you to choose one of the possible entry points. /// @@ -74,11 +62,11 @@ pub enum ParserEntryPoint { } /// Parse given tokens into the given sink as a rust file. -pub fn parse_source_file(tokens: &Tokens, tree_sink: &mut dyn TreeSink) { - parse(tokens, tree_sink, ParserEntryPoint::SourceFile); +pub fn parse_source_file(tokens: &Tokens) -> TreeTraversal { + parse(tokens, ParserEntryPoint::SourceFile) } -pub fn parse(tokens: &Tokens, tree_sink: &mut dyn TreeSink, entry_point: ParserEntryPoint) { +pub fn parse(tokens: &Tokens, entry_point: ParserEntryPoint) -> TreeTraversal { let entry_point: fn(&'_ mut parser::Parser) = match entry_point { ParserEntryPoint::SourceFile => grammar::entry_points::source_file, ParserEntryPoint::Path => grammar::entry_points::path, @@ -99,7 +87,7 @@ pub fn parse(tokens: &Tokens, tree_sink: &mut dyn TreeSink, entry_point: ParserE let mut p = parser::Parser::new(tokens); entry_point(&mut p); let events = p.finish(); - event::process(tree_sink, events); + event::process(events) } /// A parsing function for a specific braced-block. @@ -119,11 +107,11 @@ impl Reparser { /// /// Tokens must start with `{`, end with `}` and form a valid brace /// sequence. - pub fn parse(self, tokens: &Tokens, tree_sink: &mut dyn TreeSink) { + pub fn parse(self, tokens: &Tokens) -> TreeTraversal { let Reparser(r) = self; let mut p = parser::Parser::new(tokens); r(&mut p); let events = p.finish(); - event::process(tree_sink, events); + event::process(events) } } diff --git a/crates/parser/src/parser.rs b/crates/parser/src/parser.rs index 4c891108a60..4fc734f9c6d 100644 --- a/crates/parser/src/parser.rs +++ b/crates/parser/src/parser.rs @@ -8,7 +8,6 @@ use limit::Limit; use crate::{ event::Event, tokens::Tokens, - ParseError, SyntaxKind::{self, EOF, ERROR, TOMBSTONE}, TokenSet, T, }; @@ -196,7 +195,7 @@ impl<'t> Parser<'t> { /// structured errors with spans and notes, like rustc /// does. pub(crate) fn error>(&mut self, message: T) { - let msg = ParseError(Box::new(message.into())); + let msg = message.into(); self.push_event(Event::Error { msg }); } diff --git a/crates/parser/src/tree_traversal.rs b/crates/parser/src/tree_traversal.rs new file mode 100644 index 00000000000..4b3a64c85c1 --- /dev/null +++ b/crates/parser/src/tree_traversal.rs @@ -0,0 +1,67 @@ +//! TODO +use crate::SyntaxKind; + +/// Output of the parser. +#[derive(Default)] +pub struct TreeTraversal { + /// 32-bit encoding of events. If LSB is zero, then that's an index into the + /// error vector. Otherwise, it's one of the thee other variants, with data encoded as + /// + /// |16 bit kind|8 bit n_raw_tokens|4 bit tag|4 bit leftover| + /// + event: Vec, + error: Vec, +} + +pub enum TraversalStep<'a> { + Token { kind: SyntaxKind, n_raw_tokens: u8 }, + EnterNode { kind: SyntaxKind }, + LeaveNode, + Error { msg: &'a str }, +} + +impl TreeTraversal { + pub fn iter(&self) -> impl Iterator> { + self.event.iter().map(|&event| { + if event & 0b1 == 0 { + return TraversalStep::Error { msg: self.error[(event as usize) >> 1].as_str() }; + } + let tag = ((event & 0x0000_00F0) >> 4) as u8; + match tag { + 0 => { + let kind: SyntaxKind = (((event & 0xFFFF_0000) >> 16) as u16).into(); + let n_raw_tokens = ((event & 0x0000_FF00) >> 8) as u8; + TraversalStep::Token { kind, n_raw_tokens } + } + 1 => { + let kind: SyntaxKind = (((event & 0xFFFF_0000) >> 16) as u16).into(); + TraversalStep::EnterNode { kind } + } + 2 => TraversalStep::LeaveNode, + _ => unreachable!(), + } + }) + } + + pub(crate) fn token(&mut self, kind: SyntaxKind, n_tokens: u8) { + let e = ((kind as u16 as u32) << 16) | ((n_tokens as u32) << 8) | (0 << 4) | 1; + self.event.push(e) + } + + pub(crate) fn enter_node(&mut self, kind: SyntaxKind) { + let e = ((kind as u16 as u32) << 16) | (1 << 4) | 1; + self.event.push(e) + } + + pub(crate) fn leave_node(&mut self) { + let e = 2 << 4 | 1; + self.event.push(e) + } + + pub(crate) fn error(&mut self, error: String) { + let idx = self.error.len(); + self.error.push(error); + let e = (idx as u32) << 1; + self.event.push(e); + } +} diff --git a/crates/syntax/src/parsing.rs b/crates/syntax/src/parsing.rs index cba1ddde855..6721e5aa81a 100644 --- a/crates/syntax/src/parsing.rs +++ b/crates/syntax/src/parsing.rs @@ -4,24 +4,18 @@ mod text_tree_sink; mod reparsing; -use parser::SyntaxKind; -use text_tree_sink::TextTreeSink; - -use crate::{syntax_node::GreenNode, AstNode, SyntaxError, SyntaxNode}; +use crate::{ + parsing::text_tree_sink::build_tree, syntax_node::GreenNode, AstNode, SyntaxError, SyntaxNode, +}; pub(crate) use crate::parsing::reparsing::incremental_reparse; pub(crate) fn parse_text(text: &str) -> (GreenNode, Vec) { let lexed = parser::LexedStr::new(text); let parser_tokens = lexed.to_tokens(); - - let mut tree_sink = TextTreeSink::new(lexed); - - parser::parse_source_file(&parser_tokens, &mut tree_sink); - - let (tree, parser_errors) = tree_sink.finish(); - - (tree, parser_errors) + let tree_traversal = parser::parse_source_file(&parser_tokens); + let (node, errors, _eof) = build_tree(lexed, tree_traversal, false); + (node, errors) } /// Returns `text` parsed as a `T` provided there are no parse errors. @@ -34,20 +28,12 @@ pub(crate) fn parse_text_as( return Err(()); } let parser_tokens = lexed.to_tokens(); + let tree_traversal = parser::parse(&parser_tokens, entry_point); + let (node, errors, eof) = build_tree(lexed, tree_traversal, true); - let mut tree_sink = TextTreeSink::new(lexed); - - // TextTreeSink assumes that there's at least some root node to which it can attach errors and - // tokens. We arbitrarily give it a SourceFile. - use parser::TreeSink; - tree_sink.start_node(SyntaxKind::SOURCE_FILE); - parser::parse(&parser_tokens, &mut tree_sink, entry_point); - tree_sink.finish_node(); - - let (tree, parser_errors, eof) = tree_sink.finish_eof(); - if !parser_errors.is_empty() || !eof { + if !errors.is_empty() || !eof { return Err(()); } - SyntaxNode::new_root(tree).first_child().and_then(T::cast).ok_or(()) + SyntaxNode::new_root(node).first_child().and_then(T::cast).ok_or(()) } diff --git a/crates/syntax/src/parsing/reparsing.rs b/crates/syntax/src/parsing/reparsing.rs index e9567a838c6..dca97a7f583 100644 --- a/crates/syntax/src/parsing/reparsing.rs +++ b/crates/syntax/src/parsing/reparsing.rs @@ -10,7 +10,7 @@ use parser::Reparser; use text_edit::Indel; use crate::{ - parsing::text_tree_sink::TextTreeSink, + parsing::text_tree_sink::build_tree, syntax_node::{GreenNode, GreenToken, NodeOrToken, SyntaxElement, SyntaxNode}, SyntaxError, SyntaxKind::*, @@ -94,11 +94,9 @@ fn reparse_block( return None; } - let mut tree_sink = TextTreeSink::new(lexed); + let tree_traversal = reparser.parse(&parser_tokens); - reparser.parse(&parser_tokens, &mut tree_sink); - - let (green, new_parser_errors) = tree_sink.finish(); + let (green, new_parser_errors, _eof) = build_tree(lexed, tree_traversal, false); Some((node.replace_with(green), new_parser_errors, node.text_range())) } diff --git a/crates/syntax/src/parsing/text_tree_sink.rs b/crates/syntax/src/parsing/text_tree_sink.rs index c9e7feb9657..c435791746b 100644 --- a/crates/syntax/src/parsing/text_tree_sink.rs +++ b/crates/syntax/src/parsing/text_tree_sink.rs @@ -2,7 +2,7 @@ use std::mem; -use parser::{LexedStr, ParseError, TreeSink}; +use parser::{LexedStr, TreeTraversal}; use crate::{ ast, @@ -12,6 +12,36 @@ use crate::{ SyntaxTreeBuilder, TextRange, }; +pub(crate) fn build_tree( + lexed: LexedStr<'_>, + tree_traversal: TreeTraversal, + synthetic_root: bool, +) -> (GreenNode, Vec, bool) { + let mut builder = TextTreeSink::new(lexed); + + if synthetic_root { + builder.start_node(SyntaxKind::SOURCE_FILE); + } + + for event in tree_traversal.iter() { + match event { + parser::TraversalStep::Token { kind, n_raw_tokens } => { + builder.token(kind, n_raw_tokens) + } + parser::TraversalStep::EnterNode { kind } => builder.start_node(kind), + parser::TraversalStep::LeaveNode => builder.finish_node(), + parser::TraversalStep::Error { msg } => { + let text_pos = builder.lexed.text_start(builder.pos).try_into().unwrap(); + builder.inner.error(msg.to_string(), text_pos); + } + } + } + if synthetic_root { + builder.finish_node() + } + builder.finish_eof() +} + /// Bridges the parser with our specific syntax tree representation. /// /// `TextTreeSink` also handles attachment of trivia (whitespace) to nodes. @@ -28,7 +58,7 @@ enum State { PendingFinish, } -impl<'a> TreeSink for TextTreeSink<'a> { +impl<'a> TextTreeSink<'a> { fn token(&mut self, kind: SyntaxKind, n_tokens: u8) { match mem::replace(&mut self.state, State::Normal) { State::PendingStart => unreachable!(), @@ -70,11 +100,6 @@ impl<'a> TreeSink for TextTreeSink<'a> { State::Normal => (), } } - - fn error(&mut self, error: ParseError) { - let text_pos = self.lexed.text_start(self.pos).try_into().unwrap(); - self.inner.error(error, text_pos); - } } impl<'a> TextTreeSink<'a> { @@ -106,11 +131,6 @@ impl<'a> TextTreeSink<'a> { (node, errors, is_eof) } - pub(super) fn finish(self) -> (GreenNode, Vec) { - let (node, errors, _eof) = self.finish_eof(); - (node, errors) - } - fn eat_trivias(&mut self) { while self.pos < self.lexed.len() { let kind = self.lexed.kind(self.pos); diff --git a/crates/syntax/src/syntax_node.rs b/crates/syntax/src/syntax_node.rs index c95c76c0a8e..b96f10c1730 100644 --- a/crates/syntax/src/syntax_node.rs +++ b/crates/syntax/src/syntax_node.rs @@ -69,7 +69,7 @@ impl SyntaxTreeBuilder { self.inner.finish_node(); } - pub fn error(&mut self, error: parser::ParseError, text_pos: TextSize) { - self.errors.push(SyntaxError::new_at_offset(*error.0, text_pos)); + pub fn error(&mut self, error: String, text_pos: TextSize) { + self.errors.push(SyntaxError::new_at_offset(error, text_pos)); } }