bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir_expand/src/fixup.rs')
-rw-r--r--crates/hir_expand/src/fixup.rs53
1 files changed, 42 insertions, 11 deletions
diff --git a/crates/hir_expand/src/fixup.rs b/crates/hir_expand/src/fixup.rs
index f2d43f4d69..36425c8078 100644
--- a/crates/hir_expand/src/fixup.rs
+++ b/crates/hir_expand/src/fixup.rs
@@ -1,3 +1,7 @@
+//! To make attribute macros work reliably when typing, we need to take care to
+//! fix up syntax errors in the code we're passing to them.
+use std::mem;
+
use mbe::{SyntheticToken, SyntheticTokenId, TokenMap};
use rustc_hash::FxHashMap;
use syntax::{
@@ -6,16 +10,22 @@ use syntax::{
};
use tt::Subtree;
+/// The result of calculating fixes for a syntax node -- a bunch of changes
+/// (appending to and replacing nodes), the information that is needed to
+/// reverse those changes afterwards, and a token map.
#[derive(Debug)]
pub struct SyntaxFixups {
pub append: FxHashMap<SyntaxNode, Vec<SyntheticToken>>,
pub replace: FxHashMap<SyntaxNode, Vec<SyntheticToken>>,
- pub map: SyntaxFixupMap,
+ pub undo_info: SyntaxFixupUndoInfo,
+ pub token_map: TokenMap,
+ pub next_id: u32,
}
+/// This is the information needed to reverse the fixups.
#[derive(Debug, PartialEq, Eq)]
-pub struct SyntaxFixupMap {
- original: Vec<(Subtree, TokenMap)>,
+pub struct SyntaxFixupUndoInfo {
+ original: Vec<Subtree>,
}
const EMPTY_ID: SyntheticTokenId = SyntheticTokenId(!0);
@@ -25,15 +35,26 @@ pub fn fixup_syntax(node: &SyntaxNode) -> SyntaxFixups {
let mut replace = FxHashMap::default();
let mut preorder = node.preorder();
let mut original = Vec::new();
+ let mut token_map = TokenMap::default();
+ let mut next_id = 0;
while let Some(event) = preorder.next() {
let node = match event {
syntax::WalkEvent::Enter(node) => node,
syntax::WalkEvent::Leave(_) => continue,
};
+
if can_handle_error(&node) && has_error_to_handle(&node) {
// the node contains an error node, we have to completely replace it by something valid
- let original_tree = mbe::syntax_node_to_token_tree(&node);
- // TODO handle token ids / token map
+ let (original_tree, new_tmap, new_next_id) =
+ mbe::syntax_node_to_token_tree_with_modifications(
+ &node,
+ mem::take(&mut token_map),
+ next_id,
+ Default::default(),
+ Default::default(),
+ );
+ token_map = new_tmap;
+ next_id = new_next_id;
let idx = original.len() as u32;
original.push(original_tree);
let replacement = SyntheticToken {
@@ -46,6 +67,8 @@ pub fn fixup_syntax(node: &SyntaxNode) -> SyntaxFixups {
preorder.skip_subtree();
continue;
}
+
+ // In some other situations, we can fix things by just appending some tokens.
let end_range = TextRange::empty(node.text_range().end());
match_ast! {
match node {
@@ -78,7 +101,13 @@ pub fn fixup_syntax(node: &SyntaxNode) -> SyntaxFixups {
}
}
}
- SyntaxFixups { append, replace, map: SyntaxFixupMap { original } }
+ SyntaxFixups {
+ append,
+ replace,
+ token_map,
+ next_id,
+ undo_info: SyntaxFixupUndoInfo { original },
+ }
}
fn has_error(node: &SyntaxNode) -> bool {
@@ -93,7 +122,7 @@ fn has_error_to_handle(node: &SyntaxNode) -> bool {
has_error(node) || node.children().any(|c| !can_handle_error(&c) && has_error_to_handle(&c))
}
-pub fn reverse_fixups(tt: &mut Subtree, token_map: &TokenMap, fixup_map: &SyntaxFixupMap) {
+pub fn reverse_fixups(tt: &mut Subtree, token_map: &TokenMap, undo_info: &SyntaxFixupUndoInfo) {
tt.token_trees.retain(|tt| match tt {
tt::TokenTree::Leaf(leaf) => {
token_map.synthetic_token_id(leaf.id()).is_none()
@@ -102,10 +131,10 @@ pub fn reverse_fixups(tt: &mut Subtree, token_map: &TokenMap, fixup_map: &Syntax
_ => true,
});
tt.token_trees.iter_mut().for_each(|tt| match tt {
- tt::TokenTree::Subtree(tt) => reverse_fixups(tt, token_map, fixup_map),
+ tt::TokenTree::Subtree(tt) => reverse_fixups(tt, token_map, undo_info),
tt::TokenTree::Leaf(leaf) => {
if let Some(id) = token_map.synthetic_token_id(leaf.id()) {
- let (original, _original_tmap) = &fixup_map.original[id.0 as usize];
+ let original = &undo_info.original[id.0 as usize];
*tt = tt::TokenTree::Subtree(original.clone());
}
}
@@ -123,8 +152,10 @@ mod tests {
let parsed = syntax::SourceFile::parse(ra_fixture);
eprintln!("parse: {:#?}", parsed.syntax_node());
let fixups = super::fixup_syntax(&parsed.syntax_node());
- let (mut tt, tmap) = mbe::syntax_node_to_token_tree_with_modifications(
+ let (mut tt, tmap, _) = mbe::syntax_node_to_token_tree_with_modifications(
&parsed.syntax_node(),
+ fixups.token_map,
+ fixups.next_id,
fixups.replace,
fixups.append,
);
@@ -144,7 +175,7 @@ mod tests {
parse.syntax_node()
);
- reverse_fixups(&mut tt, &tmap, &fixups.map);
+ reverse_fixups(&mut tt, &tmap, &fixups.undo_info);
// the fixed-up + reversed version should be equivalent to the original input
// (but token IDs don't matter)