1 //! A simplified AST that only contains items.
14 use ast::{AstNode, NameOwner, StructKind};
18 ast_id_map::FileAstId,
20 name::{name, AsName, Name},
23 use la_arena::{Arena, Idx, RawIdx};
25 use rustc_hash::FxHashMap;
26 use smallvec::SmallVec;
27 use syntax::{ast, match_ast, SyntaxKind};
31 attr::{Attrs, RawAttrs},
33 generics::GenericParams,
34 path::{path, AssociatedTypeBinding, GenericArgs, ImportAlias, ModPath, Path, PathKind},
35 type_ref::{Mutability, TypeBound, TypeRef},
36 visibility::RawVisibility,
39 #[derive(Copy, Clone, Eq, PartialEq)]
40 pub struct RawVisibilityId(u32);
42 impl RawVisibilityId {
43 pub const PUB: Self = RawVisibilityId(u32::max_value());
44 pub const PRIV: Self = RawVisibilityId(u32::max_value() - 1);
45 pub const PUB_CRATE: Self = RawVisibilityId(u32::max_value() - 2);
48 impl fmt::Debug for RawVisibilityId {
49 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
50 let mut f = f.debug_tuple("RawVisibilityId");
52 Self::PUB => f.field(&"pub"),
53 Self::PRIV => f.field(&"pub(self)"),
54 Self::PUB_CRATE => f.field(&"pub(crate)"),
55 _ => f.field(&self.0),
61 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
62 pub struct GenericParamsId(u32);
64 impl GenericParamsId {
65 pub const EMPTY: Self = GenericParamsId(u32::max_value());
68 /// The item tree of a source file.
69 #[derive(Debug, Default, Eq, PartialEq)]
73 top_level: SmallVec<[ModItem; 1]>,
74 attrs: FxHashMap<AttrOwner, RawAttrs>,
76 data: Option<Box<ItemTreeData>>,
80 pub(crate) fn item_tree_query(db: &dyn DefDatabase, file_id: HirFileId) -> Arc<ItemTree> {
81 let _p = profile::span("item_tree_query").detail(|| format!("{:?}", file_id));
82 let syntax = if let Some(node) = db.parse_or_expand(file_id) {
83 if node.kind() == SyntaxKind::ERROR {
84 // FIXME: not 100% sure why these crop up, but return an empty tree to avoid a panic
85 return Default::default();
89 return Default::default();
92 let hygiene = Hygiene::new(db.upcast(), file_id);
93 let ctx = lower::Ctx::new(db, hygiene.clone(), file_id);
94 let mut top_attrs = None;
95 let mut item_tree = match_ast! {
97 ast::SourceFile(file) => {
98 top_attrs = Some(RawAttrs::new(&file, &hygiene));
99 ctx.lower_module_items(&file)
101 ast::MacroItems(items) => {
102 ctx.lower_module_items(&items)
104 ast::MacroStmts(stmts) => {
105 // The produced statements can include items, which should be added as top-level
107 ctx.lower_macro_stmts(stmts)
110 // Macros can expand to expressions. We return an empty item tree in this case, but
111 // still need to collect inner items.
112 ctx.lower_inner_items(e.syntax())
115 panic!("cannot create item tree from {:?} {}", syntax, syntax);
120 if let Some(attrs) = top_attrs {
121 item_tree.attrs.insert(AttrOwner::TopLevel, attrs);
123 item_tree.shrink_to_fit();
127 fn shrink_to_fit(&mut self) {
128 if let Some(data) = &mut self.data {
152 imports.shrink_to_fit();
153 extern_crates.shrink_to_fit();
154 functions.shrink_to_fit();
155 structs.shrink_to_fit();
156 fields.shrink_to_fit();
157 unions.shrink_to_fit();
158 enums.shrink_to_fit();
159 variants.shrink_to_fit();
160 consts.shrink_to_fit();
161 statics.shrink_to_fit();
162 traits.shrink_to_fit();
163 impls.shrink_to_fit();
164 type_aliases.shrink_to_fit();
165 mods.shrink_to_fit();
166 macro_calls.shrink_to_fit();
167 macro_rules.shrink_to_fit();
168 macro_defs.shrink_to_fit();
170 vis.arena.shrink_to_fit();
171 generics.arena.shrink_to_fit();
173 inner_items.shrink_to_fit();
177 /// Returns an iterator over all items located at the top level of the `HirFileId` this
178 /// `ItemTree` was created from.
179 pub fn top_level_items(&self) -> &[ModItem] {
183 /// Returns the inner attributes of the source file.
184 pub fn top_level_attrs(&self, db: &dyn DefDatabase, krate: CrateId) -> Attrs {
185 self.attrs.get(&AttrOwner::TopLevel).unwrap_or(&RawAttrs::EMPTY).clone().filter(db, krate)
188 pub(crate) fn raw_attrs(&self, of: AttrOwner) -> &RawAttrs {
189 self.attrs.get(&of).unwrap_or(&RawAttrs::EMPTY)
192 pub fn attrs(&self, db: &dyn DefDatabase, krate: CrateId, of: AttrOwner) -> Attrs {
193 self.raw_attrs(of).clone().filter(db, krate)
196 pub fn all_inner_items(&self) -> impl Iterator<Item = ModItem> + '_ {
198 Some(data) => Some(data.inner_items.values().flatten().copied()).into_iter().flatten(),
199 None => None.into_iter().flatten(),
203 pub fn inner_items_of_block(&self, block: FileAstId<ast::BlockExpr>) -> &[ModItem] {
205 Some(data) => data.inner_items.get(&block).map(|it| &**it).unwrap_or(&[]),
210 pub fn source<S: ItemTreeNode>(&self, db: &dyn DefDatabase, of: ItemTreeId<S>) -> S::Source {
211 // This unwrap cannot fail, since it has either succeeded above, or resulted in an empty
212 // ItemTree (in which case there is no valid `FileItemTreeId` to call this method with).
214 db.parse_or_expand(of.file_id).expect("parse_or_expand failed on constructed ItemTree");
216 let id = self[of.value].ast_id();
217 let map = db.ast_id_map(of.file_id);
218 let ptr = map.get(id);
222 fn data(&self) -> &ItemTreeData {
223 self.data.as_ref().expect("attempted to access data of empty ItemTree")
226 fn data_mut(&mut self) -> &mut ItemTreeData {
227 self.data.get_or_insert_with(Box::default)
231 #[derive(Default, Debug, Eq, PartialEq)]
232 struct ItemVisibilities {
233 arena: Arena<RawVisibility>,
236 impl ItemVisibilities {
237 fn alloc(&mut self, vis: RawVisibility) -> RawVisibilityId {
239 RawVisibility::Public => RawVisibilityId::PUB,
240 RawVisibility::Module(path) if path.segments.is_empty() => match &path.kind {
241 PathKind::Super(0) => RawVisibilityId::PRIV,
242 PathKind::Crate => RawVisibilityId::PUB_CRATE,
243 _ => RawVisibilityId(self.arena.alloc(vis).into_raw().into()),
245 _ => RawVisibilityId(self.arena.alloc(vis).into_raw().into()),
250 static VIS_PUB: RawVisibility = RawVisibility::Public;
251 static VIS_PRIV: RawVisibility =
252 RawVisibility::Module(ModPath { kind: PathKind::Super(0), segments: Vec::new() });
253 static VIS_PUB_CRATE: RawVisibility =
254 RawVisibility::Module(ModPath { kind: PathKind::Crate, segments: Vec::new() });
256 #[derive(Default, Debug, Eq, PartialEq)]
257 struct GenericParamsStorage {
258 arena: Arena<GenericParams>,
261 impl GenericParamsStorage {
262 fn alloc(&mut self, params: GenericParams) -> GenericParamsId {
263 if params.types.is_empty()
264 && params.lifetimes.is_empty()
265 && params.consts.is_empty()
266 && params.where_predicates.is_empty()
268 return GenericParamsId::EMPTY;
271 GenericParamsId(self.arena.alloc(params).into_raw().into())
275 static EMPTY_GENERICS: GenericParams = GenericParams {
277 lifetimes: Arena::new(),
278 consts: Arena::new(),
279 where_predicates: Vec::new(),
282 #[derive(Default, Debug, Eq, PartialEq)]
283 struct ItemTreeData {
284 imports: Arena<Import>,
285 extern_crates: Arena<ExternCrate>,
286 functions: Arena<Function>,
287 structs: Arena<Struct>,
288 fields: Arena<Field>,
289 unions: Arena<Union>,
291 variants: Arena<Variant>,
292 consts: Arena<Const>,
293 statics: Arena<Static>,
294 traits: Arena<Trait>,
296 type_aliases: Arena<TypeAlias>,
298 macro_calls: Arena<MacroCall>,
299 macro_rules: Arena<MacroRules>,
300 macro_defs: Arena<MacroDef>,
302 vis: ItemVisibilities,
303 generics: GenericParamsStorage,
305 inner_items: FxHashMap<FileAstId<ast::BlockExpr>, SmallVec<[ModItem; 1]>>,
308 #[derive(Debug, Eq, PartialEq, Hash)]
310 /// Attributes on an item.
312 /// Inner attributes of the source file.
315 Variant(Idx<Variant>),
319 macro_rules! from_attrs {
320 ( $( $var:ident($t:ty) ),+ ) => {
322 impl From<$t> for AttrOwner {
323 fn from(t: $t) -> AttrOwner {
331 from_attrs!(ModItem(ModItem), Variant(Idx<Variant>), Field(Idx<Field>));
333 /// Trait implemented by all item nodes in the item tree.
334 pub trait ItemTreeNode: Clone {
335 type Source: AstNode + Into<ast::Item>;
337 fn ast_id(&self) -> FileAstId<Self::Source>;
339 /// Looks up an instance of `Self` in an item tree.
340 fn lookup(tree: &ItemTree, index: Idx<Self>) -> &Self;
342 /// Downcasts a `ModItem` to a `FileItemTreeId` specific to this type.
343 fn id_from_mod_item(mod_item: ModItem) -> Option<FileItemTreeId<Self>>;
345 /// Upcasts a `FileItemTreeId` to a generic `ModItem`.
346 fn id_to_mod_item(id: FileItemTreeId<Self>) -> ModItem;
349 pub struct FileItemTreeId<N: ItemTreeNode> {
354 impl<N: ItemTreeNode> Clone for FileItemTreeId<N> {
355 fn clone(&self) -> Self {
356 Self { index: self.index, _p: PhantomData }
359 impl<N: ItemTreeNode> Copy for FileItemTreeId<N> {}
361 impl<N: ItemTreeNode> PartialEq for FileItemTreeId<N> {
362 fn eq(&self, other: &FileItemTreeId<N>) -> bool {
363 self.index == other.index
366 impl<N: ItemTreeNode> Eq for FileItemTreeId<N> {}
368 impl<N: ItemTreeNode> Hash for FileItemTreeId<N> {
369 fn hash<H: Hasher>(&self, state: &mut H) {
370 self.index.hash(state)
374 impl<N: ItemTreeNode> fmt::Debug for FileItemTreeId<N> {
375 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
380 pub type ItemTreeId<N> = InFile<FileItemTreeId<N>>;
382 macro_rules! mod_items {
383 ( $( $typ:ident in $fld:ident -> $ast:ty ),+ $(,)? ) => {
384 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
387 $typ(FileItemTreeId<$typ>),
392 impl From<FileItemTreeId<$typ>> for ModItem {
393 fn from(id: FileItemTreeId<$typ>) -> ModItem {
400 impl ItemTreeNode for $typ {
403 fn ast_id(&self) -> FileAstId<Self::Source> {
407 fn lookup(tree: &ItemTree, index: Idx<Self>) -> &Self {
408 &tree.data().$fld[index]
411 fn id_from_mod_item(mod_item: ModItem) -> Option<FileItemTreeId<Self>> {
412 if let ModItem::$typ(id) = mod_item {
419 fn id_to_mod_item(id: FileItemTreeId<Self>) -> ModItem {
424 impl Index<Idx<$typ>> for ItemTree {
427 fn index(&self, index: Idx<$typ>) -> &Self::Output {
428 &self.data().$fld[index]
436 Import in imports -> ast::Use,
437 ExternCrate in extern_crates -> ast::ExternCrate,
438 Function in functions -> ast::Fn,
439 Struct in structs -> ast::Struct,
440 Union in unions -> ast::Union,
441 Enum in enums -> ast::Enum,
442 Const in consts -> ast::Const,
443 Static in statics -> ast::Static,
444 Trait in traits -> ast::Trait,
445 Impl in impls -> ast::Impl,
446 TypeAlias in type_aliases -> ast::TypeAlias,
447 Mod in mods -> ast::Module,
448 MacroCall in macro_calls -> ast::MacroCall,
449 MacroRules in macro_rules -> ast::MacroRules,
450 MacroDef in macro_defs -> ast::MacroDef,
453 macro_rules! impl_index {
454 ( $($fld:ident: $t:ty),+ $(,)? ) => {
456 impl Index<Idx<$t>> for ItemTree {
459 fn index(&self, index: Idx<$t>) -> &Self::Output {
460 &self.data().$fld[index]
467 impl_index!(fields: Field, variants: Variant);
469 impl Index<RawVisibilityId> for ItemTree {
470 type Output = RawVisibility;
471 fn index(&self, index: RawVisibilityId) -> &Self::Output {
473 RawVisibilityId::PRIV => &VIS_PRIV,
474 RawVisibilityId::PUB => &VIS_PUB,
475 RawVisibilityId::PUB_CRATE => &VIS_PUB_CRATE,
476 _ => &self.data().vis.arena[Idx::from_raw(index.0.into())],
481 impl Index<GenericParamsId> for ItemTree {
482 type Output = GenericParams;
484 fn index(&self, index: GenericParamsId) -> &Self::Output {
486 GenericParamsId::EMPTY => &EMPTY_GENERICS,
487 _ => &self.data().generics.arena[Idx::from_raw(index.0.into())],
492 impl<N: ItemTreeNode> Index<FileItemTreeId<N>> for ItemTree {
494 fn index(&self, id: FileItemTreeId<N>) -> &N {
495 N::lookup(self, id.index)
499 /// A desugared `use` import.
500 #[derive(Debug, Clone, Eq, PartialEq)]
503 pub alias: Option<ImportAlias>,
504 pub visibility: RawVisibilityId,
506 /// AST ID of the `use` or `extern crate` item this import was derived from. Note that many
507 /// `Import`s can map to the same `use` item.
508 pub ast_id: FileAstId<ast::Use>,
509 /// Index of this `Import` when the containing `Use` is visited via `ModPath::expand_use_item`.
511 /// This can be used to get the `UseTree` this `Import` corresponds to and allows emitting
512 /// precise diagnostics.
516 #[derive(Debug, Clone, Eq, PartialEq)]
517 pub struct ExternCrate {
519 pub alias: Option<ImportAlias>,
520 pub visibility: RawVisibilityId,
521 pub ast_id: FileAstId<ast::ExternCrate>,
524 #[derive(Debug, Clone, Eq, PartialEq)]
525 pub struct Function {
527 pub visibility: RawVisibilityId,
528 pub generic_params: GenericParamsId,
529 pub has_self_param: bool,
532 /// Whether the function is located in an `extern` block (*not* whether it is an
533 /// `extern "abi" fn`).
535 pub params: Box<[TypeRef]>,
536 pub is_varargs: bool,
537 pub ret_type: TypeRef,
538 pub ast_id: FileAstId<ast::Fn>,
541 #[derive(Debug, Clone, Eq, PartialEq)]
544 pub visibility: RawVisibilityId,
545 pub generic_params: GenericParamsId,
547 pub ast_id: FileAstId<ast::Struct>,
548 pub kind: StructDefKind,
551 #[derive(Debug, Clone, Eq, PartialEq)]
552 pub enum StructDefKind {
553 /// `struct S { ... }` - type namespace only.
561 #[derive(Debug, Clone, Eq, PartialEq)]
564 pub visibility: RawVisibilityId,
565 pub generic_params: GenericParamsId,
567 pub ast_id: FileAstId<ast::Union>,
570 #[derive(Debug, Clone, Eq, PartialEq)]
573 pub visibility: RawVisibilityId,
574 pub generic_params: GenericParamsId,
575 pub variants: IdRange<Variant>,
576 pub ast_id: FileAstId<ast::Enum>,
579 #[derive(Debug, Clone, Eq, PartialEq)]
581 /// const _: () = ();
582 pub name: Option<Name>,
583 pub visibility: RawVisibilityId,
584 pub type_ref: TypeRef,
585 pub ast_id: FileAstId<ast::Const>,
588 #[derive(Debug, Clone, Eq, PartialEq)]
591 pub visibility: RawVisibilityId,
593 /// Whether the static is in an `extern` block.
595 pub type_ref: TypeRef,
596 pub ast_id: FileAstId<ast::Static>,
599 #[derive(Debug, Clone, Eq, PartialEq)]
602 pub visibility: RawVisibilityId,
603 pub generic_params: GenericParamsId,
605 pub items: Box<[AssocItem]>,
606 pub ast_id: FileAstId<ast::Trait>,
609 #[derive(Debug, Clone, Eq, PartialEq)]
611 pub generic_params: GenericParamsId,
612 pub target_trait: Option<TypeRef>,
613 pub target_type: TypeRef,
614 pub is_negative: bool,
615 pub items: Box<[AssocItem]>,
616 pub ast_id: FileAstId<ast::Impl>,
619 #[derive(Debug, Clone, PartialEq, Eq)]
620 pub struct TypeAlias {
622 pub visibility: RawVisibilityId,
623 /// Bounds on the type alias itself. Only valid in trait declarations, eg. `type Assoc: Copy;`.
624 pub bounds: Box<[TypeBound]>,
625 pub generic_params: GenericParamsId,
626 pub type_ref: Option<TypeRef>,
628 pub ast_id: FileAstId<ast::TypeAlias>,
631 #[derive(Debug, Clone, Eq, PartialEq)]
634 pub visibility: RawVisibilityId,
636 pub ast_id: FileAstId<ast::Module>,
639 #[derive(Debug, Clone, Eq, PartialEq)]
642 Inline { items: Box<[ModItem]> },
648 #[derive(Debug, Clone, Eq, PartialEq)]
649 pub struct MacroCall {
650 /// Path to the called macro.
652 pub ast_id: FileAstId<ast::MacroCall>,
655 #[derive(Debug, Clone, Eq, PartialEq)]
656 pub struct MacroRules {
657 /// The name of the declared macro.
659 pub ast_id: FileAstId<ast::MacroRules>,
662 /// "Macros 2.0" macro definition.
663 #[derive(Debug, Clone, Eq, PartialEq)]
664 pub struct MacroDef {
666 pub visibility: RawVisibilityId,
667 pub ast_id: FileAstId<ast::MacroDef>,
670 macro_rules! impl_froms {
671 ($e:ident { $($v:ident ($t:ty)),* $(,)? }) => {
673 impl From<$t> for $e {
674 fn from(it: $t) -> $e {
683 pub fn as_assoc_item(&self) -> Option<AssocItem> {
686 | ModItem::ExternCrate(_)
694 | ModItem::MacroRules(_)
695 | ModItem::MacroDef(_) => None,
696 ModItem::MacroCall(call) => Some(AssocItem::MacroCall(*call)),
697 ModItem::Const(konst) => Some(AssocItem::Const(*konst)),
698 ModItem::TypeAlias(alias) => Some(AssocItem::TypeAlias(*alias)),
699 ModItem::Function(func) => Some(AssocItem::Function(*func)),
703 pub fn downcast<N: ItemTreeNode>(self) -> Option<FileItemTreeId<N>> {
704 N::id_from_mod_item(self)
707 pub fn ast_id(&self, tree: &ItemTree) -> FileAstId<ast::Item> {
709 ModItem::Import(it) => tree[it.index].ast_id().upcast(),
710 ModItem::ExternCrate(it) => tree[it.index].ast_id().upcast(),
711 ModItem::Function(it) => tree[it.index].ast_id().upcast(),
712 ModItem::Struct(it) => tree[it.index].ast_id().upcast(),
713 ModItem::Union(it) => tree[it.index].ast_id().upcast(),
714 ModItem::Enum(it) => tree[it.index].ast_id().upcast(),
715 ModItem::Const(it) => tree[it.index].ast_id().upcast(),
716 ModItem::Static(it) => tree[it.index].ast_id().upcast(),
717 ModItem::Trait(it) => tree[it.index].ast_id().upcast(),
718 ModItem::Impl(it) => tree[it.index].ast_id().upcast(),
719 ModItem::TypeAlias(it) => tree[it.index].ast_id().upcast(),
720 ModItem::Mod(it) => tree[it.index].ast_id().upcast(),
721 ModItem::MacroCall(it) => tree[it.index].ast_id().upcast(),
722 ModItem::MacroRules(it) => tree[it.index].ast_id().upcast(),
723 ModItem::MacroDef(it) => tree[it.index].ast_id().upcast(),
728 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
730 Function(FileItemTreeId<Function>),
731 TypeAlias(FileItemTreeId<TypeAlias>),
732 Const(FileItemTreeId<Const>),
733 MacroCall(FileItemTreeId<MacroCall>),
736 impl_froms!(AssocItem {
737 Function(FileItemTreeId<Function>),
738 TypeAlias(FileItemTreeId<TypeAlias>),
739 Const(FileItemTreeId<Const>),
740 MacroCall(FileItemTreeId<MacroCall>),
743 impl From<AssocItem> for ModItem {
744 fn from(item: AssocItem) -> Self {
746 AssocItem::Function(it) => it.into(),
747 AssocItem::TypeAlias(it) => it.into(),
748 AssocItem::Const(it) => it.into(),
749 AssocItem::MacroCall(it) => it.into(),
754 #[derive(Debug, Eq, PartialEq)]
760 pub struct IdRange<T> {
766 fn new(range: Range<Idx<T>>) -> Self {
767 Self { range: range.start.into_raw().into()..range.end.into_raw().into(), _p: PhantomData }
771 impl<T> Iterator for IdRange<T> {
773 fn next(&mut self) -> Option<Self::Item> {
774 self.range.next().map(|raw| Idx::from_raw(raw.into()))
778 impl<T> fmt::Debug for IdRange<T> {
779 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
780 f.debug_tuple(&format!("IdRange::<{}>", type_name::<T>())).field(&self.range).finish()
784 impl<T> Clone for IdRange<T> {
785 fn clone(&self) -> Self {
786 Self { range: self.range.clone(), _p: PhantomData }
790 impl<T> PartialEq for IdRange<T> {
791 fn eq(&self, other: &Self) -> bool {
792 self.range == other.range
796 impl<T> Eq for IdRange<T> {}
798 #[derive(Debug, Clone, PartialEq, Eq)]
800 Record(IdRange<Field>),
801 Tuple(IdRange<Field>),
805 /// A single field of an enum variant or struct
806 #[derive(Debug, Clone, PartialEq, Eq)]
809 pub type_ref: TypeRef,
810 pub visibility: RawVisibilityId,