1 //! A simplified AST that only contains items.
14 use arena::{Arena, Idx, RawId};
15 use ast::{AstNode, AttrsOwner, NameOwner, StructKind};
19 ast_id_map::FileAstId,
21 name::{name, AsName, Name},
24 use rustc_hash::FxHashMap;
25 use smallvec::SmallVec;
26 use syntax::{ast, match_ast};
30 attr::{Attrs, RawAttrs},
32 generics::GenericParams,
33 path::{path, AssociatedTypeBinding, GenericArgs, ImportAlias, ModPath, Path, PathKind},
34 type_ref::{Mutability, TypeBound, TypeRef},
35 visibility::RawVisibility,
38 #[derive(Copy, Clone, Eq, PartialEq)]
39 pub struct RawVisibilityId(u32);
41 impl RawVisibilityId {
42 pub const PUB: Self = RawVisibilityId(u32::max_value());
43 pub const PRIV: Self = RawVisibilityId(u32::max_value() - 1);
44 pub const PUB_CRATE: Self = RawVisibilityId(u32::max_value() - 2);
47 impl fmt::Debug for RawVisibilityId {
48 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
49 let mut f = f.debug_tuple("RawVisibilityId");
51 Self::PUB => f.field(&"pub"),
52 Self::PRIV => f.field(&"pub(self)"),
53 Self::PUB_CRATE => f.field(&"pub(crate)"),
54 _ => f.field(&self.0),
60 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
61 pub struct GenericParamsId(u32);
63 impl GenericParamsId {
64 pub const EMPTY: Self = GenericParamsId(u32::max_value());
67 /// The item tree of a source file.
68 #[derive(Debug, Eq, PartialEq)]
70 top_level: SmallVec<[ModItem; 1]>,
71 attrs: FxHashMap<AttrOwner, RawAttrs>,
72 inner_items: FxHashMap<FileAstId<ast::Item>, SmallVec<[ModItem; 1]>>,
74 data: Option<Box<ItemTreeData>>,
78 pub fn item_tree_query(db: &dyn DefDatabase, file_id: HirFileId) -> Arc<ItemTree> {
79 let _p = profile::span("item_tree_query").detail(|| format!("{:?}", file_id));
80 let syntax = if let Some(node) = db.parse_or_expand(file_id) {
83 return Arc::new(Self::empty());
86 let hygiene = Hygiene::new(db.upcast(), file_id);
87 let ctx = lower::Ctx::new(db, hygiene.clone(), file_id);
88 let mut top_attrs = None;
89 let mut item_tree = match_ast! {
91 ast::SourceFile(file) => {
92 top_attrs = Some(RawAttrs::new(&file, &hygiene));
93 ctx.lower_module_items(&file)
95 ast::MacroItems(items) => {
96 ctx.lower_module_items(&items)
98 ast::MacroStmts(stmts) => {
99 ctx.lower_inner_items(stmts.syntax())
101 // Macros can expand to expressions. We return an empty item tree in this case, but
102 // still need to collect inner items.
104 ctx.lower_inner_items(e.syntax())
107 panic!("cannot create item tree from {:?}", syntax);
112 if let Some(attrs) = top_attrs {
113 item_tree.attrs.insert(AttrOwner::TopLevel, attrs);
115 item_tree.shrink_to_fit();
121 top_level: Default::default(),
122 attrs: Default::default(),
123 inner_items: Default::default(),
124 data: Default::default(),
128 fn shrink_to_fit(&mut self) {
129 if let Some(data) = &mut self.data {
153 imports.shrink_to_fit();
154 extern_crates.shrink_to_fit();
155 functions.shrink_to_fit();
156 structs.shrink_to_fit();
157 fields.shrink_to_fit();
158 unions.shrink_to_fit();
159 enums.shrink_to_fit();
160 variants.shrink_to_fit();
161 consts.shrink_to_fit();
162 statics.shrink_to_fit();
163 traits.shrink_to_fit();
164 impls.shrink_to_fit();
165 type_aliases.shrink_to_fit();
166 mods.shrink_to_fit();
167 macro_calls.shrink_to_fit();
168 macro_rules.shrink_to_fit();
169 macro_defs.shrink_to_fit();
170 exprs.shrink_to_fit();
172 vis.arena.shrink_to_fit();
173 generics.arena.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 /// Returns the lowered inner items that `ast` corresponds to.
198 /// Most AST items are lowered to a single `ModItem`, but some (eg. `use` items) may be lowered
199 /// to multiple items in the `ItemTree`.
200 pub fn inner_items(&self, ast: FileAstId<ast::Item>) -> &[ModItem] {
201 &self.inner_items[&ast]
204 pub fn all_inner_items(&self) -> impl Iterator<Item = ModItem> + '_ {
205 self.inner_items.values().flatten().copied()
208 pub fn source<S: ItemTreeNode>(&self, db: &dyn DefDatabase, of: ItemTreeId<S>) -> S::Source {
209 // This unwrap cannot fail, since it has either succeeded above, or resulted in an empty
210 // ItemTree (in which case there is no valid `FileItemTreeId` to call this method with).
212 db.parse_or_expand(of.file_id).expect("parse_or_expand failed on constructed ItemTree");
214 let id = self[of.value].ast_id();
215 let map = db.ast_id_map(of.file_id);
216 let ptr = map.get(id);
220 fn data(&self) -> &ItemTreeData {
221 self.data.as_ref().expect("attempted to access data of empty ItemTree")
224 fn data_mut(&mut self) -> &mut ItemTreeData {
225 self.data.get_or_insert_with(Box::default)
229 #[derive(Default, Debug, Eq, PartialEq)]
230 struct ItemVisibilities {
231 arena: Arena<RawVisibility>,
234 impl ItemVisibilities {
235 fn alloc(&mut self, vis: RawVisibility) -> RawVisibilityId {
237 RawVisibility::Public => RawVisibilityId::PUB,
238 RawVisibility::Module(path) if path.segments.is_empty() => match &path.kind {
239 PathKind::Super(0) => RawVisibilityId::PRIV,
240 PathKind::Crate => RawVisibilityId::PUB_CRATE,
241 _ => RawVisibilityId(self.arena.alloc(vis).into_raw().into()),
243 _ => RawVisibilityId(self.arena.alloc(vis).into_raw().into()),
248 static VIS_PUB: RawVisibility = RawVisibility::Public;
249 static VIS_PRIV: RawVisibility =
250 RawVisibility::Module(ModPath { kind: PathKind::Super(0), segments: Vec::new() });
251 static VIS_PUB_CRATE: RawVisibility =
252 RawVisibility::Module(ModPath { kind: PathKind::Crate, segments: Vec::new() });
254 #[derive(Default, Debug, Eq, PartialEq)]
255 struct GenericParamsStorage {
256 arena: Arena<GenericParams>,
259 impl GenericParamsStorage {
260 fn alloc(&mut self, params: GenericParams) -> GenericParamsId {
261 if params.types.is_empty()
262 && params.lifetimes.is_empty()
263 && params.where_predicates.is_empty()
265 return GenericParamsId::EMPTY;
268 GenericParamsId(self.arena.alloc(params).into_raw().into())
272 static EMPTY_GENERICS: GenericParams =
273 GenericParams { types: Arena::new(), lifetimes: Arena::new(), where_predicates: Vec::new() };
275 #[derive(Default, Debug, Eq, PartialEq)]
276 struct ItemTreeData {
277 imports: Arena<Import>,
278 extern_crates: Arena<ExternCrate>,
279 functions: Arena<Function>,
280 structs: Arena<Struct>,
281 fields: Arena<Field>,
282 unions: Arena<Union>,
284 variants: Arena<Variant>,
285 consts: Arena<Const>,
286 statics: Arena<Static>,
287 traits: Arena<Trait>,
289 type_aliases: Arena<TypeAlias>,
291 macro_calls: Arena<MacroCall>,
292 macro_rules: Arena<MacroRules>,
293 macro_defs: Arena<MacroDef>,
296 vis: ItemVisibilities,
297 generics: GenericParamsStorage,
300 #[derive(Debug, Eq, PartialEq, Hash)]
302 /// Attributes on an item.
304 /// Inner attributes of the source file.
307 Variant(Idx<Variant>),
311 macro_rules! from_attrs {
312 ( $( $var:ident($t:ty) ),+ ) => {
314 impl From<$t> for AttrOwner {
315 fn from(t: $t) -> AttrOwner {
323 from_attrs!(ModItem(ModItem), Variant(Idx<Variant>), Field(Idx<Field>));
325 /// Trait implemented by all item nodes in the item tree.
326 pub trait ItemTreeNode: Clone {
327 type Source: AstNode + Into<ast::Item>;
329 fn ast_id(&self) -> FileAstId<Self::Source>;
331 /// Looks up an instance of `Self` in an item tree.
332 fn lookup(tree: &ItemTree, index: Idx<Self>) -> &Self;
334 /// Downcasts a `ModItem` to a `FileItemTreeId` specific to this type.
335 fn id_from_mod_item(mod_item: ModItem) -> Option<FileItemTreeId<Self>>;
337 /// Upcasts a `FileItemTreeId` to a generic `ModItem`.
338 fn id_to_mod_item(id: FileItemTreeId<Self>) -> ModItem;
341 pub struct FileItemTreeId<N: ItemTreeNode> {
346 impl<N: ItemTreeNode> Clone for FileItemTreeId<N> {
347 fn clone(&self) -> Self {
348 Self { index: self.index, _p: PhantomData }
351 impl<N: ItemTreeNode> Copy for FileItemTreeId<N> {}
353 impl<N: ItemTreeNode> PartialEq for FileItemTreeId<N> {
354 fn eq(&self, other: &FileItemTreeId<N>) -> bool {
355 self.index == other.index
358 impl<N: ItemTreeNode> Eq for FileItemTreeId<N> {}
360 impl<N: ItemTreeNode> Hash for FileItemTreeId<N> {
361 fn hash<H: Hasher>(&self, state: &mut H) {
362 self.index.hash(state)
366 impl<N: ItemTreeNode> fmt::Debug for FileItemTreeId<N> {
367 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
372 pub type ItemTreeId<N> = InFile<FileItemTreeId<N>>;
374 macro_rules! mod_items {
375 ( $( $typ:ident in $fld:ident -> $ast:ty ),+ $(,)? ) => {
376 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
379 $typ(FileItemTreeId<$typ>),
384 impl From<FileItemTreeId<$typ>> for ModItem {
385 fn from(id: FileItemTreeId<$typ>) -> ModItem {
392 impl ItemTreeNode for $typ {
395 fn ast_id(&self) -> FileAstId<Self::Source> {
399 fn lookup(tree: &ItemTree, index: Idx<Self>) -> &Self {
400 &tree.data().$fld[index]
403 fn id_from_mod_item(mod_item: ModItem) -> Option<FileItemTreeId<Self>> {
404 if let ModItem::$typ(id) = mod_item {
411 fn id_to_mod_item(id: FileItemTreeId<Self>) -> ModItem {
416 impl Index<Idx<$typ>> for ItemTree {
419 fn index(&self, index: Idx<$typ>) -> &Self::Output {
420 &self.data().$fld[index]
428 Import in imports -> ast::Use,
429 ExternCrate in extern_crates -> ast::ExternCrate,
430 Function in functions -> ast::Fn,
431 Struct in structs -> ast::Struct,
432 Union in unions -> ast::Union,
433 Enum in enums -> ast::Enum,
434 Const in consts -> ast::Const,
435 Static in statics -> ast::Static,
436 Trait in traits -> ast::Trait,
437 Impl in impls -> ast::Impl,
438 TypeAlias in type_aliases -> ast::TypeAlias,
439 Mod in mods -> ast::Module,
440 MacroCall in macro_calls -> ast::MacroCall,
441 MacroRules in macro_rules -> ast::MacroRules,
442 MacroDef in macro_defs -> ast::MacroDef,
445 macro_rules! impl_index {
446 ( $($fld:ident: $t:ty),+ $(,)? ) => {
448 impl Index<Idx<$t>> for ItemTree {
451 fn index(&self, index: Idx<$t>) -> &Self::Output {
452 &self.data().$fld[index]
459 impl_index!(fields: Field, variants: Variant, exprs: Expr);
461 impl Index<RawVisibilityId> for ItemTree {
462 type Output = RawVisibility;
463 fn index(&self, index: RawVisibilityId) -> &Self::Output {
465 RawVisibilityId::PRIV => &VIS_PRIV,
466 RawVisibilityId::PUB => &VIS_PUB,
467 RawVisibilityId::PUB_CRATE => &VIS_PUB_CRATE,
468 _ => &self.data().vis.arena[Idx::from_raw(index.0.into())],
473 impl Index<GenericParamsId> for ItemTree {
474 type Output = GenericParams;
476 fn index(&self, index: GenericParamsId) -> &Self::Output {
478 GenericParamsId::EMPTY => &EMPTY_GENERICS,
479 _ => &self.data().generics.arena[Idx::from_raw(index.0.into())],
484 impl<N: ItemTreeNode> Index<FileItemTreeId<N>> for ItemTree {
486 fn index(&self, id: FileItemTreeId<N>) -> &N {
487 N::lookup(self, id.index)
491 /// A desugared `use` import.
492 #[derive(Debug, Clone, Eq, PartialEq)]
495 pub alias: Option<ImportAlias>,
496 pub visibility: RawVisibilityId,
498 pub is_prelude: bool,
499 /// AST ID of the `use` or `extern crate` item this import was derived from. Note that many
500 /// `Import`s can map to the same `use` item.
501 pub ast_id: FileAstId<ast::Use>,
502 /// Index of this `Import` when the containing `Use` is visited via `ModPath::expand_use_item`.
504 /// This can be used to get the `UseTree` this `Import` corresponds to and allows emitting
505 /// precise diagnostics.
509 #[derive(Debug, Clone, Eq, PartialEq)]
510 pub struct ExternCrate {
512 pub alias: Option<ImportAlias>,
513 pub visibility: RawVisibilityId,
514 /// Whether this is a `#[macro_use] extern crate ...`.
515 pub is_macro_use: bool,
516 pub ast_id: FileAstId<ast::ExternCrate>,
519 #[derive(Debug, Clone, Eq, PartialEq)]
520 pub struct Function {
522 pub visibility: RawVisibilityId,
523 pub generic_params: GenericParamsId,
524 pub has_self_param: bool,
527 /// Whether the function is located in an `extern` block (*not* whether it is an
528 /// `extern "abi" fn`).
530 pub params: Box<[TypeRef]>,
531 pub is_varargs: bool,
532 pub ret_type: TypeRef,
533 pub ast_id: FileAstId<ast::Fn>,
536 #[derive(Debug, Clone, Eq, PartialEq)]
539 pub visibility: RawVisibilityId,
540 pub generic_params: GenericParamsId,
542 pub ast_id: FileAstId<ast::Struct>,
543 pub kind: StructDefKind,
546 #[derive(Debug, Clone, Eq, PartialEq)]
547 pub enum StructDefKind {
548 /// `struct S { ... }` - type namespace only.
556 #[derive(Debug, Clone, Eq, PartialEq)]
559 pub visibility: RawVisibilityId,
560 pub generic_params: GenericParamsId,
562 pub ast_id: FileAstId<ast::Union>,
565 #[derive(Debug, Clone, Eq, PartialEq)]
568 pub visibility: RawVisibilityId,
569 pub generic_params: GenericParamsId,
570 pub variants: IdRange<Variant>,
571 pub ast_id: FileAstId<ast::Enum>,
574 #[derive(Debug, Clone, Eq, PartialEq)]
576 /// const _: () = ();
577 pub name: Option<Name>,
578 pub visibility: RawVisibilityId,
579 pub type_ref: TypeRef,
580 pub ast_id: FileAstId<ast::Const>,
583 #[derive(Debug, Clone, Eq, PartialEq)]
586 pub visibility: RawVisibilityId,
588 /// Whether the static is in an `extern` block.
590 pub type_ref: TypeRef,
591 pub ast_id: FileAstId<ast::Static>,
594 #[derive(Debug, Clone, Eq, PartialEq)]
597 pub visibility: RawVisibilityId,
598 pub generic_params: GenericParamsId,
600 pub items: Box<[AssocItem]>,
601 pub ast_id: FileAstId<ast::Trait>,
604 #[derive(Debug, Clone, Eq, PartialEq)]
606 pub generic_params: GenericParamsId,
607 pub target_trait: Option<TypeRef>,
608 pub target_type: TypeRef,
609 pub is_negative: bool,
610 pub items: Box<[AssocItem]>,
611 pub ast_id: FileAstId<ast::Impl>,
614 #[derive(Debug, Clone, PartialEq, Eq)]
615 pub struct TypeAlias {
617 pub visibility: RawVisibilityId,
618 /// Bounds on the type alias itself. Only valid in trait declarations, eg. `type Assoc: Copy;`.
619 pub bounds: Box<[TypeBound]>,
620 pub generic_params: GenericParamsId,
621 pub type_ref: Option<TypeRef>,
623 pub ast_id: FileAstId<ast::TypeAlias>,
626 #[derive(Debug, Clone, Eq, PartialEq)]
629 pub visibility: RawVisibilityId,
631 pub ast_id: FileAstId<ast::Module>,
634 #[derive(Debug, Clone, Eq, PartialEq)]
637 Inline { items: Box<[ModItem]> },
643 #[derive(Debug, Clone, Eq, PartialEq)]
644 pub struct MacroCall {
645 /// Path to the called macro.
647 pub ast_id: FileAstId<ast::MacroCall>,
650 #[derive(Debug, Clone, Eq, PartialEq)]
651 pub struct MacroRules {
652 /// The name of the declared macro.
654 pub ast_id: FileAstId<ast::MacroRules>,
657 /// "Macros 2.0" macro definition.
658 #[derive(Debug, Clone, Eq, PartialEq)]
659 pub struct MacroDef {
661 pub visibility: RawVisibilityId,
662 pub ast_id: FileAstId<ast::MacroDef>,
665 // NB: There's no `FileAstId` for `Expr`. The only case where this would be useful is for array
666 // lengths, but we don't do much with them yet.
667 #[derive(Debug, Clone, Eq, PartialEq)]
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,