bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/tt/src/buffer.rs')
-rw-r--r--crates/tt/src/buffer.rs43
1 files changed, 26 insertions, 17 deletions
diff --git a/crates/tt/src/buffer.rs b/crates/tt/src/buffer.rs
index 02a722895a..78cf4b956d 100644
--- a/crates/tt/src/buffer.rs
+++ b/crates/tt/src/buffer.rs
@@ -1,16 +1,16 @@
//! Stateful iteration over token trees.
//!
//! We use this as the source of tokens for parser.
-use crate::{Leaf, Subtree, TokenTree, TokenTreesView};
+use crate::{Leaf, Subtree, TokenTree, TokenTreesView, dispatch_ref};
-pub struct Cursor<'a, Span> {
- buffer: &'a [TokenTree<Span>],
+pub struct Cursor<'a> {
+ buffer: TokenTreesView<'a>,
index: usize,
subtrees_stack: Vec<usize>,
}
-impl<'a, Span: Copy> Cursor<'a, Span> {
- pub fn new(buffer: &'a [TokenTree<Span>]) -> Self {
+impl<'a> Cursor<'a> {
+ pub fn new(buffer: TokenTreesView<'a>) -> Self {
Self { buffer, index: 0, subtrees_stack: Vec::new() }
}
@@ -23,16 +23,22 @@ impl<'a, Span: Copy> Cursor<'a, Span> {
self.subtrees_stack.is_empty()
}
- fn last_subtree(&self) -> Option<(usize, &'a Subtree<Span>)> {
+ fn at(&self, idx: usize) -> Option<TokenTree> {
+ dispatch_ref! {
+ match self.buffer.repr => tt => Some(tt.get(idx)?.to_api(self.buffer.span_parts))
+ }
+ }
+
+ fn last_subtree(&self) -> Option<(usize, Subtree)> {
self.subtrees_stack.last().map(|&subtree_idx| {
- let TokenTree::Subtree(subtree) = &self.buffer[subtree_idx] else {
+ let Some(TokenTree::Subtree(subtree)) = self.at(subtree_idx) else {
panic!("subtree pointing to non-subtree");
};
(subtree_idx, subtree)
})
}
- pub fn end(&mut self) -> &'a Subtree<Span> {
+ pub fn end(&mut self) -> Subtree {
let (last_subtree_idx, last_subtree) =
self.last_subtree().expect("called `Cursor::end()` without an open subtree");
// +1 because `Subtree.len` excludes the subtree itself.
@@ -46,14 +52,14 @@ impl<'a, Span: Copy> Cursor<'a, Span> {
}
/// Returns the `TokenTree` at the cursor if it is not at the end of a subtree.
- pub fn token_tree(&self) -> Option<&'a TokenTree<Span>> {
+ pub fn token_tree(&self) -> Option<TokenTree> {
if let Some((last_subtree_idx, last_subtree)) = self.last_subtree() {
// +1 because `Subtree.len` excludes the subtree itself.
if last_subtree_idx + last_subtree.usize_len() + 1 == self.index {
return None;
}
}
- self.buffer.get(self.index)
+ self.at(self.index)
}
/// Bump the cursor, and enters a subtree if it is on one.
@@ -66,7 +72,7 @@ impl<'a, Span: Copy> Cursor<'a, Span> {
"called `Cursor::bump()` when at the end of a subtree"
);
}
- if let TokenTree::Subtree(_) = self.buffer[self.index] {
+ if let Some(TokenTree::Subtree(_)) = self.at(self.index) {
self.subtrees_stack.push(self.index);
}
self.index += 1;
@@ -81,13 +87,13 @@ impl<'a, Span: Copy> Cursor<'a, Span> {
}
}
// +1 because `Subtree.len` excludes the subtree itself.
- if let TokenTree::Subtree(_) = self.buffer[self.index] {
+ if let Some(TokenTree::Subtree(_)) = self.at(self.index) {
self.subtrees_stack.push(self.index);
}
self.index += 1;
}
- pub fn peek_two_leaves(&self) -> Option<[&'a Leaf<Span>; 2]> {
+ pub fn peek_two_leaves(&self) -> Option<[Leaf; 2]> {
if let Some((last_subtree_idx, last_subtree)) = self.last_subtree() {
// +1 because `Subtree.len` excludes the subtree itself.
let last_end = last_subtree_idx + last_subtree.usize_len() + 1;
@@ -95,14 +101,17 @@ impl<'a, Span: Copy> Cursor<'a, Span> {
return None;
}
}
- self.buffer.get(self.index..self.index + 2).and_then(|it| match it {
- [TokenTree::Leaf(a), TokenTree::Leaf(b)] => Some([a, b]),
+ self.at(self.index).zip(self.at(self.index + 1)).and_then(|it| match it {
+ (TokenTree::Leaf(a), TokenTree::Leaf(b)) => Some([a, b]),
_ => None,
})
}
- pub fn crossed(&self) -> TokenTreesView<'a, Span> {
+ pub fn crossed(&self) -> TokenTreesView<'a> {
assert!(self.is_root());
- TokenTreesView::new(&self.buffer[..self.index])
+ TokenTreesView {
+ repr: self.buffer.repr.get(..self.index).unwrap(),
+ span_parts: self.buffer.span_parts,
+ }
}
}