diff options
Diffstat (limited to 'crates/ra_hir/src/ids.rs')
-rw-r--r-- | crates/ra_hir/src/ids.rs | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/crates/ra_hir/src/ids.rs b/crates/ra_hir/src/ids.rs index 3db757778..8ac49eba3 100644 --- a/crates/ra_hir/src/ids.rs +++ b/crates/ra_hir/src/ids.rs | |||
@@ -253,13 +253,17 @@ impl SourceFileItems { | |||
253 | } | 253 | } |
254 | 254 | ||
255 | fn init(&mut self, source_file: &SourceFile) { | 255 | fn init(&mut self, source_file: &SourceFile) { |
256 | source_file.syntax().descendants().for_each(|it| { | 256 | // By walking the tree in bread-first order we make sure that parents |
257 | // get lower ids then children. That is, addding a new child does not | ||
258 | // change parent's id. This means that, say, adding a new function to a | ||
259 | // trait does not chage ids of top-level items, which helps caching. | ||
260 | bfs(source_file.syntax(), |it| { | ||
257 | if let Some(module_item) = ast::ModuleItem::cast(it) { | 261 | if let Some(module_item) = ast::ModuleItem::cast(it) { |
258 | self.alloc(module_item.syntax().to_owned()); | 262 | self.alloc(module_item.syntax().to_owned()); |
259 | } else if let Some(macro_call) = ast::MacroCall::cast(it) { | 263 | } else if let Some(macro_call) = ast::MacroCall::cast(it) { |
260 | self.alloc(macro_call.syntax().to_owned()); | 264 | self.alloc(macro_call.syntax().to_owned()); |
261 | } | 265 | } |
262 | }); | 266 | }) |
263 | } | 267 | } |
264 | 268 | ||
265 | fn alloc(&mut self, item: TreePtr<SyntaxNode>) -> SourceFileItemId { | 269 | fn alloc(&mut self, item: TreePtr<SyntaxNode>) -> SourceFileItemId { |
@@ -305,3 +309,16 @@ impl std::ops::Index<SourceFileItemId> for SourceFileItems { | |||
305 | &self.arena[idx] | 309 | &self.arena[idx] |
306 | } | 310 | } |
307 | } | 311 | } |
312 | |||
313 | /// Walks the subtree in bfs order, calling `f` for each node. | ||
314 | fn bfs(node: &SyntaxNode, mut f: impl FnMut(&SyntaxNode)) { | ||
315 | let mut curr_layer = vec![node]; | ||
316 | let mut next_layer = vec![]; | ||
317 | while !curr_layer.is_empty() { | ||
318 | curr_layer.drain(..).for_each(|node| { | ||
319 | next_layer.extend(node.children()); | ||
320 | f(node); | ||
321 | }); | ||
322 | std::mem::swap(&mut curr_layer, &mut next_layer); | ||
323 | } | ||
324 | } | ||