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Diffstat (limited to 'crates/hir_expand/src/ast_id_map.rs')
| -rw-r--r-- | crates/hir_expand/src/ast_id_map.rs | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/crates/hir_expand/src/ast_id_map.rs b/crates/hir_expand/src/ast_id_map.rs index 64387b8148..9db2bc6410 100644 --- a/crates/hir_expand/src/ast_id_map.rs +++ b/crates/hir_expand/src/ast_id_map.rs @@ -61,13 +61,29 @@ impl<N: AstNode> FileAstId<N> { type ErasedFileAstId = Idx<SyntaxNodePtr>; /// Maps items' `SyntaxNode`s to `ErasedFileAstId`s and back. -#[derive(Debug, PartialEq, Eq, Default)] +#[derive(Default)] pub struct AstIdMap { arena: Arena<SyntaxNodePtr>, - map: FxHashMap<SyntaxNodePtr, ErasedFileAstId>, + /// Reversed mapping lazily derived from [`self.arena`]. + /// + /// FIXE: Do not store `SyntaxNodePtr` twice. + map: once_cell::sync::OnceCell<FxHashMap<SyntaxNodePtr, ErasedFileAstId>>, _c: Count<Self>, } +impl fmt::Debug for AstIdMap { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("AstIdMap").field("arena", &self.arena).finish() + } +} + +impl PartialEq for AstIdMap { + fn eq(&self, other: &Self) -> bool { + self.arena == other.arena + } +} +impl Eq for AstIdMap {} + impl AstIdMap { pub(crate) fn from_source(node: &SyntaxNode) -> AstIdMap { assert!(node.parent().is_none()); @@ -91,9 +107,11 @@ impl AstIdMap { } } }); - res.map.extend(res.arena.iter().map(|(idx, ptr)| (ptr.clone(), idx))); res } + fn map(&self) -> &FxHashMap<SyntaxNodePtr, ErasedFileAstId> { + self.map.get_or_init(|| self.arena.iter().map(|(idx, ptr)| (ptr.clone(), idx)).collect()) + } pub fn ast_id<N: AstNode>(&self, item: &N) -> FileAstId<N> { let raw = self.erased_ast_id(item.syntax()); @@ -102,7 +120,7 @@ impl AstIdMap { fn erased_ast_id(&self, item: &SyntaxNode) -> ErasedFileAstId { let ptr = SyntaxNodePtr::new(item); - *self.map.get(&ptr).unwrap_or_else(|| { + *self.map().get(&ptr).unwrap_or_else(|| { panic!( "Can't find {:?} in AstIdMap:\n{:?}", item, |