bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/tt_iter.rs')
-rw-r--r--crates/mbe/src/tt_iter.rs51
1 files changed, 22 insertions, 29 deletions
diff --git a/crates/mbe/src/tt_iter.rs b/crates/mbe/src/tt_iter.rs
index d05e84b0f0..2d2dbd8994 100644
--- a/crates/mbe/src/tt_iter.rs
+++ b/crates/mbe/src/tt_iter.rs
@@ -1,11 +1,10 @@
//! A "Parser" structure for token trees. We use this when parsing a declarative
//! macro definition into a list of patterns and templates.
-use crate::{to_parser_tokens::to_parser_tokens, ExpandError, ExpandResult, ParserEntryPoint};
+use crate::{to_parser_input::to_parser_input, 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<Option<tt::TokenTree>> {
- 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();
+ let buffer = TokenBuffer::from_tokens(self.inner.as_slice());
+ let parser_input = to_parser_input(&buffer);
+ let tree_traversal = parser::parse(&parser_input, entry_point);
+
+ let mut cursor = buffer.begin();
+ let mut error = false;
+ for step in tree_traversal.iter() {
+ match step {
+ parser::Step::Token { kind, mut n_input_tokens } => {
+ if kind == SyntaxKind::LIFETIME_IDENT {
+ n_input_tokens = 2;
+ }
+ for _ in 0..n_input_tokens {
+ cursor = 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;
+ parser::Step::Enter { .. } | parser::Step::Exit => (),
+ parser::Step::Error { .. } => 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 };
-
- parser::parse(&parser_tokens, &mut sink, entry_point);
-
- 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);
}