bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-def/src/item_tree.rs')
-rw-r--r--crates/hir-def/src/item_tree.rs39
1 files changed, 35 insertions, 4 deletions
diff --git a/crates/hir-def/src/item_tree.rs b/crates/hir-def/src/item_tree.rs
index c3b7a78301..be74d15814 100644
--- a/crates/hir-def/src/item_tree.rs
+++ b/crates/hir-def/src/item_tree.rs
@@ -48,6 +48,7 @@ use either::Either;
use hir_expand::{attrs::RawAttrs, name::Name, ExpandTo, HirFileId, InFile};
use intern::Interned;
use la_arena::{Arena, Idx, IdxRange, RawIdx};
+use once_cell::sync::OnceCell;
use rustc_hash::FxHashMap;
use smallvec::SmallVec;
use span::{AstIdNode, FileAstId, SyntaxContextId};
@@ -100,6 +101,7 @@ pub struct ItemTree {
impl ItemTree {
pub(crate) fn file_item_tree_query(db: &dyn DefDatabase, file_id: HirFileId) -> Arc<ItemTree> {
let _p = tracing::info_span!("file_item_tree_query", ?file_id).entered();
+ static EMPTY: OnceCell<Arc<ItemTree>> = OnceCell::new();
let syntax = db.parse_or_expand(file_id);
@@ -131,18 +133,47 @@ impl ItemTree {
if let Some(attrs) = top_attrs {
item_tree.attrs.insert(AttrOwner::TopLevel, attrs);
}
- item_tree.shrink_to_fit();
- Arc::new(item_tree)
+ if item_tree.data.is_none() && item_tree.top_level.is_empty() && item_tree.attrs.is_empty()
+ {
+ EMPTY
+ .get_or_init(|| {
+ Arc::new(ItemTree {
+ top_level: SmallVec::new_const(),
+ attrs: FxHashMap::default(),
+ data: None,
+ })
+ })
+ .clone()
+ } else {
+ item_tree.shrink_to_fit();
+ Arc::new(item_tree)
+ }
}
pub(crate) fn block_item_tree_query(db: &dyn DefDatabase, block: BlockId) -> Arc<ItemTree> {
+ let _p = tracing::info_span!("block_item_tree_query", ?block).entered();
+ static EMPTY: OnceCell<Arc<ItemTree>> = OnceCell::new();
+
let loc = block.lookup(db);
let block = loc.ast_id.to_node(db.upcast());
let ctx = lower::Ctx::new(db, loc.ast_id.file_id);
let mut item_tree = ctx.lower_block(&block);
- item_tree.shrink_to_fit();
- Arc::new(item_tree)
+ if item_tree.data.is_none() && item_tree.top_level.is_empty() && item_tree.attrs.is_empty()
+ {
+ EMPTY
+ .get_or_init(|| {
+ Arc::new(ItemTree {
+ top_level: SmallVec::new_const(),
+ attrs: FxHashMap::default(),
+ data: None,
+ })
+ })
+ .clone()
+ } else {
+ item_tree.shrink_to_fit();
+ Arc::new(item_tree)
+ }
}
/// Returns an iterator over all items located at the top level of the `HirFileId` this