]>
Commit | Line | Data |
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2b03887a | 1 | use super::errors::{InvalidAbi, InvalidAbiSuggestion, MisplacedRelaxTraitBound}; |
923072b8 | 2 | use super::ResolverAstLoweringExt; |
9c376795 | 3 | use super::{AstOwner, ImplTraitContext, ImplTraitPosition}; |
064997fb | 4 | use super::{FnDeclKind, LoweringContext, ParamMode}; |
dfeec247 | 5 | |
ba9703b0 | 6 | use rustc_ast::ptr::P; |
5e7ed085 | 7 | use rustc_ast::visit::AssocCtxt; |
3dfed10e | 8 | use rustc_ast::*; |
5e7ed085 | 9 | use rustc_data_structures::sorted_map::SortedMap; |
9ffffee4 | 10 | use rustc_errors::ErrorGuaranteed; |
dfeec247 XL |
11 | use rustc_hir as hir; |
12 | use rustc_hir::def::{DefKind, Res}; | |
5e7ed085 | 13 | use rustc_hir::def_id::{LocalDefId, CRATE_DEF_ID}; |
04454e1e | 14 | use rustc_hir::PredicateOrigin; |
5e7ed085 | 15 | use rustc_index::vec::{Idx, IndexVec}; |
064997fb | 16 | use rustc_middle::ty::{DefIdTree, ResolverAstLowering, TyCtxt}; |
9ffffee4 | 17 | use rustc_span::edit_distance::find_best_match_for_name; |
04454e1e | 18 | use rustc_span::source_map::DesugaringKind; |
f9f354fc | 19 | use rustc_span::symbol::{kw, sym, Ident}; |
2b03887a | 20 | use rustc_span::{Span, Symbol}; |
60c5eb7d | 21 | use rustc_target::spec::abi; |
dfeec247 | 22 | use smallvec::{smallvec, SmallVec}; |
487cf647 | 23 | use thin_vec::ThinVec; |
6a06907d | 24 | |
5e7ed085 | 25 | pub(super) struct ItemLowerer<'a, 'hir> { |
064997fb | 26 | pub(super) tcx: TyCtxt<'hir>, |
923072b8 | 27 | pub(super) resolver: &'a mut ResolverAstLowering, |
5e7ed085 FG |
28 | pub(super) ast_index: &'a IndexVec<LocalDefId, AstOwner<'a>>, |
29 | pub(super) owners: &'a mut IndexVec<LocalDefId, hir::MaybeOwner<&'hir hir::OwnerInfo<'hir>>>, | |
416331ca XL |
30 | } |
31 | ||
5e7ed085 FG |
32 | /// When we have a ty alias we *may* have two where clauses. To give the best diagnostics, we set the span |
33 | /// to the where clause that is preferred, if it exists. Otherwise, it sets the span to the other where | |
34 | /// clause if it exists. | |
35 | fn add_ty_alias_where_clause( | |
36 | generics: &mut ast::Generics, | |
37 | mut where_clauses: (TyAliasWhereClause, TyAliasWhereClause), | |
38 | prefer_first: bool, | |
39 | ) { | |
40 | if !prefer_first { | |
41 | where_clauses = (where_clauses.1, where_clauses.0); | |
42 | } | |
43 | if where_clauses.0.0 || !where_clauses.1.0 { | |
44 | generics.where_clause.has_where_token = where_clauses.0.0; | |
45 | generics.where_clause.span = where_clauses.0.1; | |
46 | } else { | |
47 | generics.where_clause.has_where_token = where_clauses.1.0; | |
48 | generics.where_clause.span = where_clauses.1.1; | |
416331ca XL |
49 | } |
50 | } | |
51 | ||
5e7ed085 FG |
52 | impl<'a, 'hir> ItemLowerer<'a, 'hir> { |
53 | fn with_lctx( | |
54 | &mut self, | |
55 | owner: NodeId, | |
56 | f: impl FnOnce(&mut LoweringContext<'_, 'hir>) -> hir::OwnerNode<'hir>, | |
57 | ) { | |
58 | let mut lctx = LoweringContext { | |
59 | // Pseudo-globals. | |
064997fb | 60 | tcx: self.tcx, |
5e7ed085 | 61 | resolver: self.resolver, |
064997fb | 62 | arena: self.tcx.hir_arena, |
5e7ed085 FG |
63 | |
64 | // HirId handling. | |
65 | bodies: Vec::new(), | |
66 | attrs: SortedMap::default(), | |
487cf647 | 67 | children: Vec::default(), |
2b03887a | 68 | current_hir_id_owner: hir::CRATE_OWNER_ID, |
5e7ed085 FG |
69 | item_local_id_counter: hir::ItemLocalId::new(0), |
70 | node_id_to_local_id: Default::default(), | |
5e7ed085 FG |
71 | trait_map: Default::default(), |
72 | ||
73 | // Lowering state. | |
74 | catch_scope: None, | |
75 | loop_scope: None, | |
76 | is_in_loop_condition: false, | |
77 | is_in_trait_impl: false, | |
78 | is_in_dyn_type: false, | |
5e7ed085 FG |
79 | generator_kind: None, |
80 | task_context: None, | |
81 | current_item: None, | |
923072b8 FG |
82 | impl_trait_defs: Vec::new(), |
83 | impl_trait_bounds: Vec::new(), | |
04454e1e | 84 | allow_try_trait: Some([sym::try_trait_v2, sym::yeet_desugar_details][..].into()), |
487cf647 | 85 | allow_gen_future: Some([sym::gen_future, sym::closure_track_caller][..].into()), |
5e7ed085 | 86 | allow_into_future: Some([sym::into_future][..].into()), |
f2b60f7d | 87 | generics_def_id_map: Default::default(), |
5e7ed085 FG |
88 | }; |
89 | lctx.with_hir_id_owner(owner, |lctx| f(lctx)); | |
3c0e092e | 90 | |
5e7ed085 FG |
91 | for (def_id, info) in lctx.children { |
92 | self.owners.ensure_contains_elem(def_id, || hir::MaybeOwner::Phantom); | |
93 | debug_assert!(matches!(self.owners[def_id], hir::MaybeOwner::Phantom)); | |
94 | self.owners[def_id] = info; | |
95 | } | |
416331ca XL |
96 | } |
97 | ||
5e7ed085 FG |
98 | pub(super) fn lower_node( |
99 | &mut self, | |
100 | def_id: LocalDefId, | |
101 | ) -> hir::MaybeOwner<&'hir hir::OwnerInfo<'hir>> { | |
102 | self.owners.ensure_contains_elem(def_id, || hir::MaybeOwner::Phantom); | |
103 | if let hir::MaybeOwner::Phantom = self.owners[def_id] { | |
104 | let node = self.ast_index[def_id]; | |
105 | match node { | |
106 | AstOwner::NonOwner => {} | |
107 | AstOwner::Crate(c) => self.lower_crate(c), | |
108 | AstOwner::Item(item) => self.lower_item(item), | |
109 | AstOwner::AssocItem(item, ctxt) => self.lower_assoc_item(item, ctxt), | |
110 | AstOwner::ForeignItem(item) => self.lower_foreign_item(item), | |
3dfed10e | 111 | } |
3dfed10e | 112 | } |
3dfed10e | 113 | |
5e7ed085 | 114 | self.owners[def_id] |
416331ca | 115 | } |
fc512014 | 116 | |
923072b8 | 117 | #[instrument(level = "debug", skip(self, c))] |
5e7ed085 | 118 | fn lower_crate(&mut self, c: &Crate) { |
923072b8 | 119 | debug_assert_eq!(self.resolver.node_id_to_def_id[&CRATE_NODE_ID], CRATE_DEF_ID); |
5e7ed085 | 120 | self.with_lctx(CRATE_NODE_ID, |lctx| { |
04454e1e | 121 | let module = lctx.lower_mod(&c.items, &c.spans); |
5e7ed085 | 122 | lctx.lower_attrs(hir::CRATE_HIR_ID, &c.attrs); |
f2b60f7d | 123 | hir::OwnerNode::Crate(module) |
5e7ed085 | 124 | }) |
fc512014 | 125 | } |
416331ca | 126 | |
923072b8 | 127 | #[instrument(level = "debug", skip(self))] |
5e7ed085 FG |
128 | fn lower_item(&mut self, item: &Item) { |
129 | self.with_lctx(item.id, |lctx| hir::OwnerNode::Item(lctx.lower_item(item))) | |
416331ca XL |
130 | } |
131 | ||
5e7ed085 | 132 | fn lower_assoc_item(&mut self, item: &AssocItem, ctxt: AssocCtxt) { |
923072b8 | 133 | let def_id = self.resolver.node_id_to_def_id[&item.id]; |
e1599b0c | 134 | |
064997fb | 135 | let parent_id = self.tcx.local_parent(def_id); |
04454e1e | 136 | let parent_hir = self.lower_node(parent_id).unwrap(); |
5e7ed085 FG |
137 | self.with_lctx(item.id, |lctx| { |
138 | // Evaluate with the lifetimes in `params` in-scope. | |
139 | // This is used to track which lifetimes have already been defined, | |
140 | // and which need to be replicated when lowering an async fn. | |
04454e1e | 141 | match parent_hir.node().expect_item().kind { |
487cf647 | 142 | hir::ItemKind::Impl(hir::Impl { of_trait, .. }) => { |
5e7ed085 | 143 | lctx.is_in_trait_impl = of_trait.is_some(); |
5e7ed085 FG |
144 | } |
145 | _ => {} | |
146 | }; | |
e1599b0c | 147 | |
5e7ed085 FG |
148 | match ctxt { |
149 | AssocCtxt::Trait => hir::OwnerNode::TraitItem(lctx.lower_trait_item(item)), | |
150 | AssocCtxt::Impl => hir::OwnerNode::ImplItem(lctx.lower_impl_item(item)), | |
151 | } | |
152 | }) | |
153 | } | |
e1599b0c | 154 | |
5e7ed085 FG |
155 | fn lower_foreign_item(&mut self, item: &ForeignItem) { |
156 | self.with_lctx(item.id, |lctx| hir::OwnerNode::ForeignItem(lctx.lower_foreign_item(item))) | |
e1599b0c | 157 | } |
5e7ed085 | 158 | } |
e1599b0c | 159 | |
5e7ed085 | 160 | impl<'hir> LoweringContext<'_, 'hir> { |
f2b60f7d FG |
161 | pub(super) fn lower_mod( |
162 | &mut self, | |
163 | items: &[P<Item>], | |
164 | spans: &ModSpans, | |
165 | ) -> &'hir hir::Mod<'hir> { | |
166 | self.arena.alloc(hir::Mod { | |
04454e1e FG |
167 | spans: hir::ModSpans { |
168 | inner_span: self.lower_span(spans.inner_span), | |
169 | inject_use_span: self.lower_span(spans.inject_use_span), | |
170 | }, | |
c295e0f8 | 171 | item_ids: self.arena.alloc_from_iter(items.iter().flat_map(|x| self.lower_item_ref(x))), |
f2b60f7d | 172 | }) |
416331ca XL |
173 | } |
174 | ||
c295e0f8 | 175 | pub(super) fn lower_item_ref(&mut self, i: &Item) -> SmallVec<[hir::ItemId; 1]> { |
2b03887a FG |
176 | let mut node_ids = |
177 | smallvec![hir::ItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } }]; | |
487cf647 FG |
178 | if let ItemKind::Use(use_tree) = &i.kind { |
179 | self.lower_item_id_use_tree(use_tree, &mut node_ids); | |
c295e0f8 | 180 | } |
dfeec247 | 181 | node_ids |
416331ca XL |
182 | } |
183 | ||
487cf647 FG |
184 | fn lower_item_id_use_tree(&mut self, tree: &UseTree, vec: &mut SmallVec<[hir::ItemId; 1]>) { |
185 | match &tree.kind { | |
186 | UseTreeKind::Nested(nested_vec) => { | |
dfeec247 | 187 | for &(ref nested, id) in nested_vec { |
2b03887a FG |
188 | vec.push(hir::ItemId { |
189 | owner_id: hir::OwnerId { def_id: self.local_def_id(id) }, | |
190 | }); | |
487cf647 | 191 | self.lower_item_id_use_tree(nested, vec); |
416331ca | 192 | } |
dfeec247 | 193 | } |
487cf647 | 194 | UseTreeKind::Simple(..) | UseTreeKind::Glob => {} |
416331ca XL |
195 | } |
196 | } | |
197 | ||
c295e0f8 | 198 | fn lower_item(&mut self, i: &Item) -> &'hir hir::Item<'hir> { |
416331ca | 199 | let mut ident = i.ident; |
04454e1e | 200 | let vis_span = self.lower_span(i.vis.span); |
6a06907d XL |
201 | let hir_id = self.lower_node_id(i.id); |
202 | let attrs = self.lower_attrs(hir_id, &i.attrs); | |
04454e1e | 203 | let kind = self.lower_item_kind(i.span, i.id, hir_id, &mut ident, attrs, vis_span, &i.kind); |
c295e0f8 | 204 | let item = hir::Item { |
2b03887a | 205 | owner_id: hir_id.expect_owner(), |
94222f64 XL |
206 | ident: self.lower_ident(ident), |
207 | kind, | |
04454e1e | 208 | vis_span, |
94222f64 | 209 | span: self.lower_span(i.span), |
c295e0f8 XL |
210 | }; |
211 | self.arena.alloc(item) | |
416331ca XL |
212 | } |
213 | ||
214 | fn lower_item_kind( | |
215 | &mut self, | |
dfeec247 | 216 | span: Span, |
416331ca | 217 | id: NodeId, |
6a06907d | 218 | hir_id: hir::HirId, |
416331ca | 219 | ident: &mut Ident, |
6a06907d | 220 | attrs: Option<&'hir [Attribute]>, |
04454e1e | 221 | vis_span: Span, |
416331ca | 222 | i: &ItemKind, |
dfeec247 | 223 | ) -> hir::ItemKind<'hir> { |
487cf647 FG |
224 | match i { |
225 | ItemKind::ExternCrate(orig_name) => hir::ItemKind::ExternCrate(*orig_name), | |
226 | ItemKind::Use(use_tree) => { | |
416331ca | 227 | // Start with an empty prefix. |
487cf647 | 228 | let prefix = Path { segments: ThinVec::new(), span: use_tree.span, tokens: None }; |
416331ca | 229 | |
04454e1e | 230 | self.lower_use_tree(use_tree, &prefix, id, vis_span, ident, attrs) |
416331ca | 231 | } |
487cf647 | 232 | ItemKind::Static(t, m, e) => { |
74b04a01 | 233 | let (ty, body_id) = self.lower_const_item(t, span, e.as_deref()); |
487cf647 | 234 | hir::ItemKind::Static(ty, *m, body_id) |
416331ca | 235 | } |
487cf647 | 236 | ItemKind::Const(_, t, e) => { |
74b04a01 XL |
237 | let (ty, body_id) = self.lower_const_item(t, span, e.as_deref()); |
238 | hir::ItemKind::Const(ty, body_id) | |
416331ca | 239 | } |
3c0e092e | 240 | ItemKind::Fn(box Fn { |
487cf647 FG |
241 | sig: FnSig { decl, header, span: fn_sig_span }, |
242 | generics, | |
243 | body, | |
3c0e092e XL |
244 | .. |
245 | }) => { | |
416331ca XL |
246 | self.with_new_scopes(|this| { |
247 | this.current_item = Some(ident.span); | |
248 | ||
249 | // Note: we don't need to change the return type from `T` to | |
250 | // `impl Future<Output = T>` here because lower_body | |
251 | // only cares about the input argument patterns in the function | |
252 | // declaration (decl), not the return types. | |
74b04a01 | 253 | let asyncness = header.asyncness; |
487cf647 FG |
254 | let body_id = this.lower_maybe_async_body( |
255 | span, | |
256 | hir_id, | |
257 | &decl, | |
258 | asyncness, | |
259 | body.as_deref(), | |
260 | ); | |
416331ca | 261 | |
9c376795 FG |
262 | let itctx = ImplTraitContext::Universal; |
263 | let (generics, decl) = this.lower_generics(generics, id, &itctx, |this| { | |
923072b8 | 264 | let ret_id = asyncness.opt_return_id(); |
487cf647 | 265 | this.lower_fn_decl(&decl, id, *fn_sig_span, FnDeclKind::Fn, ret_id) |
923072b8 | 266 | }); |
3dfed10e XL |
267 | let sig = hir::FnSig { |
268 | decl, | |
487cf647 FG |
269 | header: this.lower_fn_header(*header), |
270 | span: this.lower_span(*fn_sig_span), | |
3dfed10e | 271 | }; |
60c5eb7d | 272 | hir::ItemKind::Fn(sig, generics, body_id) |
416331ca XL |
273 | }) |
274 | } | |
487cf647 | 275 | ItemKind::Mod(_, mod_kind) => match mod_kind { |
04454e1e FG |
276 | ModKind::Loaded(items, _, spans) => { |
277 | hir::ItemKind::Mod(self.lower_mod(items, spans)) | |
6a06907d XL |
278 | } |
279 | ModKind::Unloaded => panic!("`mod` items should have been loaded by now"), | |
280 | }, | |
487cf647 | 281 | ItemKind::ForeignMod(fm) => hir::ItemKind::ForeignMod { |
94222f64 XL |
282 | abi: fm.abi.map_or(abi::Abi::FALLBACK, |abi| self.lower_abi(abi)), |
283 | items: self | |
284 | .arena | |
285 | .alloc_from_iter(fm.items.iter().map(|x| self.lower_foreign_item_ref(x))), | |
286 | }, | |
487cf647 | 287 | ItemKind::GlobalAsm(asm) => hir::ItemKind::GlobalAsm(self.lower_inline_asm(span, asm)), |
9ffffee4 | 288 | ItemKind::TyAlias(box TyAlias { generics, where_clauses, ty, .. }) => { |
f035d41b XL |
289 | // We lower |
290 | // | |
291 | // type Foo = impl Trait | |
292 | // | |
293 | // to | |
294 | // | |
295 | // type Foo = Foo1 | |
296 | // opaque type Foo1: Trait | |
5e7ed085 | 297 | let mut generics = generics.clone(); |
487cf647 | 298 | add_ty_alias_where_clause(&mut generics, *where_clauses, true); |
923072b8 | 299 | let (generics, ty) = self.lower_generics( |
5e7ed085 | 300 | &generics, |
923072b8 | 301 | id, |
f2b60f7d | 302 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
9ffffee4 FG |
303 | |this| match ty { |
304 | None => { | |
305 | let guar = this.tcx.sess.delay_span_bug( | |
306 | span, | |
307 | "expected to lower type alias type, but it was missing", | |
308 | ); | |
309 | this.arena.alloc(this.ty(span, hir::TyKind::Err(guar))) | |
310 | } | |
311 | Some(ty) => this.lower_ty(ty, &ImplTraitContext::TypeAliasesOpaqueTy), | |
312 | }, | |
5099ac24 | 313 | ); |
74b04a01 XL |
314 | hir::ItemKind::TyAlias(ty, generics) |
315 | } | |
487cf647 | 316 | ItemKind::Enum(enum_definition, generics) => { |
923072b8 | 317 | let (generics, variants) = self.lower_generics( |
5099ac24 | 318 | generics, |
923072b8 | 319 | id, |
f2b60f7d | 320 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
321 | |this| { |
322 | this.arena.alloc_from_iter( | |
323 | enum_definition.variants.iter().map(|x| this.lower_variant(x)), | |
324 | ) | |
325 | }, | |
326 | ); | |
327 | hir::ItemKind::Enum(hir::EnumDef { variants }, generics) | |
328 | } | |
487cf647 | 329 | ItemKind::Struct(struct_def, generics) => { |
923072b8 FG |
330 | let (generics, struct_def) = self.lower_generics( |
331 | generics, | |
332 | id, | |
f2b60f7d | 333 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
334 | |this| this.lower_variant_data(hir_id, struct_def), |
335 | ); | |
336 | hir::ItemKind::Struct(struct_def, generics) | |
416331ca | 337 | } |
487cf647 | 338 | ItemKind::Union(vdata, generics) => { |
923072b8 FG |
339 | let (generics, vdata) = self.lower_generics( |
340 | generics, | |
341 | id, | |
f2b60f7d | 342 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
343 | |this| this.lower_variant_data(hir_id, vdata), |
344 | ); | |
345 | hir::ItemKind::Union(vdata, generics) | |
416331ca | 346 | } |
3c0e092e | 347 | ItemKind::Impl(box Impl { |
416331ca XL |
348 | unsafety, |
349 | polarity, | |
350 | defaultness, | |
dfeec247 | 351 | constness, |
487cf647 FG |
352 | generics: ast_generics, |
353 | of_trait: trait_ref, | |
354 | self_ty: ty, | |
355 | items: impl_items, | |
5869c6ff | 356 | }) => { |
416331ca XL |
357 | // Lower the "impl header" first. This ordering is important |
358 | // for in-band lifetimes! Consider `'a` here: | |
359 | // | |
360 | // impl Foo<'a> for u32 { | |
361 | // fn method(&'a self) { .. } | |
362 | // } | |
363 | // | |
364 | // Because we start by lowering the `Foo<'a> for u32` | |
365 | // part, we will add `'a` to the list of generics on | |
366 | // the impl. When we then encounter it later in the | |
367 | // method, it will not be considered an in-band | |
368 | // lifetime to be added, but rather a reference to a | |
369 | // parent lifetime. | |
9c376795 | 370 | let itctx = ImplTraitContext::Universal; |
04454e1e | 371 | let (generics, (trait_ref, lowered_ty)) = |
9c376795 | 372 | self.lower_generics(ast_generics, id, &itctx, |this| { |
416331ca | 373 | let trait_ref = trait_ref.as_ref().map(|trait_ref| { |
5099ac24 FG |
374 | this.lower_trait_ref( |
375 | trait_ref, | |
f2b60f7d | 376 | &ImplTraitContext::Disallowed(ImplTraitPosition::Trait), |
5099ac24 | 377 | ) |
416331ca XL |
378 | }); |
379 | ||
9ffffee4 FG |
380 | let lowered_ty = this.lower_ty( |
381 | ty, | |
382 | &ImplTraitContext::Disallowed(ImplTraitPosition::ImplSelf), | |
383 | ); | |
416331ca XL |
384 | |
385 | (trait_ref, lowered_ty) | |
dfeec247 | 386 | }); |
416331ca | 387 | |
04454e1e FG |
388 | let new_impl_items = self |
389 | .arena | |
390 | .alloc_from_iter(impl_items.iter().map(|item| self.lower_impl_item_ref(item))); | |
391 | ||
ba9703b0 XL |
392 | // `defaultness.has_value()` is never called for an `impl`, always `true` in order |
393 | // to not cause an assertion failure inside the `lower_defaultness` function. | |
394 | let has_val = true; | |
487cf647 | 395 | let (defaultness, defaultness_span) = self.lower_defaultness(*defaultness, has_val); |
94222f64 XL |
396 | let polarity = match polarity { |
397 | ImplPolarity::Positive => ImplPolarity::Positive, | |
487cf647 | 398 | ImplPolarity::Negative(s) => ImplPolarity::Negative(self.lower_span(*s)), |
94222f64 | 399 | }; |
04454e1e | 400 | hir::ItemKind::Impl(self.arena.alloc(hir::Impl { |
487cf647 | 401 | unsafety: self.lower_unsafety(*unsafety), |
60c5eb7d | 402 | polarity, |
ba9703b0 XL |
403 | defaultness, |
404 | defaultness_span, | |
487cf647 | 405 | constness: self.lower_constness(*constness), |
416331ca | 406 | generics, |
dfeec247 XL |
407 | of_trait: trait_ref, |
408 | self_ty: lowered_ty, | |
409 | items: new_impl_items, | |
04454e1e | 410 | })) |
416331ca | 411 | } |
487cf647 | 412 | ItemKind::Trait(box Trait { is_auto, unsafety, generics, bounds, items }) => { |
923072b8 FG |
413 | let (generics, (unsafety, items, bounds)) = self.lower_generics( |
414 | generics, | |
415 | id, | |
f2b60f7d | 416 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
417 | |this| { |
418 | let bounds = this.lower_param_bounds( | |
419 | bounds, | |
f2b60f7d | 420 | &ImplTraitContext::Disallowed(ImplTraitPosition::Bound), |
923072b8 FG |
421 | ); |
422 | let items = this.arena.alloc_from_iter( | |
423 | items.iter().map(|item| this.lower_trait_item_ref(item)), | |
424 | ); | |
487cf647 | 425 | let unsafety = this.lower_unsafety(*unsafety); |
923072b8 FG |
426 | (unsafety, items, bounds) |
427 | }, | |
5099ac24 | 428 | ); |
487cf647 | 429 | hir::ItemKind::Trait(*is_auto, unsafety, generics, bounds, items) |
416331ca | 430 | } |
487cf647 | 431 | ItemKind::TraitAlias(generics, bounds) => { |
923072b8 | 432 | let (generics, bounds) = self.lower_generics( |
5099ac24 | 433 | generics, |
923072b8 | 434 | id, |
f2b60f7d | 435 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
436 | |this| { |
437 | this.lower_param_bounds( | |
438 | bounds, | |
f2b60f7d | 439 | &ImplTraitContext::Disallowed(ImplTraitPosition::Bound), |
923072b8 FG |
440 | ) |
441 | }, | |
442 | ); | |
443 | hir::ItemKind::TraitAlias(generics, bounds) | |
444 | } | |
487cf647 FG |
445 | ItemKind::MacroDef(MacroDef { body, macro_rules }) => { |
446 | let body = P(self.lower_delim_args(body)); | |
923072b8 | 447 | let macro_kind = self.resolver.decl_macro_kind(self.local_def_id(id)); |
487cf647 | 448 | hir::ItemKind::Macro(ast::MacroDef { body, macro_rules: *macro_rules }, macro_kind) |
94222f64 XL |
449 | } |
450 | ItemKind::MacCall(..) => { | |
ba9703b0 | 451 | panic!("`TyMac` should have been expanded by now") |
dfeec247 | 452 | } |
416331ca | 453 | } |
416331ca XL |
454 | } |
455 | ||
74b04a01 XL |
456 | fn lower_const_item( |
457 | &mut self, | |
458 | ty: &Ty, | |
459 | span: Span, | |
460 | body: Option<&Expr>, | |
461 | ) -> (&'hir hir::Ty<'hir>, hir::BodyId) { | |
9ffffee4 | 462 | let ty = self.lower_ty(ty, &ImplTraitContext::Disallowed(ImplTraitPosition::ConstTy)); |
74b04a01 XL |
463 | (ty, self.lower_const_body(span, body)) |
464 | } | |
465 | ||
923072b8 | 466 | #[instrument(level = "debug", skip(self))] |
416331ca XL |
467 | fn lower_use_tree( |
468 | &mut self, | |
469 | tree: &UseTree, | |
470 | prefix: &Path, | |
471 | id: NodeId, | |
04454e1e | 472 | vis_span: Span, |
416331ca | 473 | ident: &mut Ident, |
6a06907d | 474 | attrs: Option<&'hir [Attribute]>, |
dfeec247 | 475 | ) -> hir::ItemKind<'hir> { |
416331ca | 476 | let path = &tree.prefix; |
dfeec247 | 477 | let segments = prefix.segments.iter().chain(path.segments.iter()).cloned().collect(); |
416331ca XL |
478 | |
479 | match tree.kind { | |
487cf647 | 480 | UseTreeKind::Simple(rename) => { |
416331ca XL |
481 | *ident = tree.ident(); |
482 | ||
483 | // First, apply the prefix to the path. | |
1b1a35ee | 484 | let mut path = Path { segments, span: path.span, tokens: None }; |
416331ca XL |
485 | |
486 | // Correctly resolve `self` imports. | |
487 | if path.segments.len() > 1 | |
488 | && path.segments.last().unwrap().ident.name == kw::SelfLower | |
489 | { | |
490 | let _ = path.segments.pop(); | |
491 | if rename.is_none() { | |
492 | *ident = path.segments.last().unwrap().ident; | |
493 | } | |
494 | } | |
495 | ||
487cf647 FG |
496 | let res = |
497 | self.expect_full_res_from_use(id).map(|res| self.lower_res(res)).collect(); | |
498 | let path = self.lower_use_path(res, &path, ParamMode::Explicit); | |
416331ca XL |
499 | hir::ItemKind::Use(path, hir::UseKind::Single) |
500 | } | |
501 | UseTreeKind::Glob => { | |
487cf647 FG |
502 | let res = self.expect_full_res(id); |
503 | let res = smallvec![self.lower_res(res)]; | |
504 | let path = Path { segments, span: path.span, tokens: None }; | |
505 | let path = self.lower_use_path(res, &path, ParamMode::Explicit); | |
416331ca XL |
506 | hir::ItemKind::Use(path, hir::UseKind::Glob) |
507 | } | |
508 | UseTreeKind::Nested(ref trees) => { | |
509 | // Nested imports are desugared into simple imports. | |
510 | // So, if we start with | |
511 | // | |
512 | // ``` | |
513 | // pub(x) use foo::{a, b}; | |
514 | // ``` | |
515 | // | |
516 | // we will create three items: | |
517 | // | |
518 | // ``` | |
519 | // pub(x) use foo::a; | |
520 | // pub(x) use foo::b; | |
521 | // pub(x) use foo::{}; // <-- this is called the `ListStem` | |
522 | // ``` | |
523 | // | |
524 | // The first two are produced by recursively invoking | |
525 | // `lower_use_tree` (and indeed there may be things | |
9c376795 | 526 | // like `use foo::{a::{b, c}}` and so forth). They |
416331ca XL |
527 | // wind up being directly added to |
528 | // `self.items`. However, the structure of this | |
529 | // function also requires us to return one item, and | |
530 | // for that we return the `{}` import (called the | |
531 | // `ListStem`). | |
532 | ||
1b1a35ee | 533 | let prefix = Path { segments, span: prefix.span.to(path.span), tokens: None }; |
416331ca XL |
534 | |
535 | // Add all the nested `PathListItem`s to the HIR. | |
536 | for &(ref use_tree, id) in trees { | |
923072b8 | 537 | let new_hir_id = self.local_def_id(id); |
416331ca XL |
538 | |
539 | let mut prefix = prefix.clone(); | |
540 | ||
541 | // Give the segments new node-ids since they are being cloned. | |
542 | for seg in &mut prefix.segments { | |
2b03887a FG |
543 | // Give the cloned segment the same resolution information |
544 | // as the old one (this is needed for stability checking). | |
545 | let new_id = self.next_node_id(); | |
546 | self.resolver.clone_res(seg.id, new_id); | |
547 | seg.id = new_id; | |
416331ca XL |
548 | } |
549 | ||
550 | // Each `use` import is an item and thus are owners of the | |
551 | // names in the path. Up to this point the nested import is | |
552 | // the current owner, since we want each desugared import to | |
553 | // own its own names, we have to adjust the owner before | |
554 | // lowering the rest of the import. | |
555 | self.with_hir_id_owner(id, |this| { | |
416331ca XL |
556 | let mut ident = *ident; |
557 | ||
dfeec247 | 558 | let kind = |
04454e1e | 559 | this.lower_use_tree(use_tree, &prefix, id, vis_span, &mut ident, attrs); |
6a06907d | 560 | if let Some(attrs) = attrs { |
3c0e092e | 561 | this.attrs.insert(hir::ItemLocalId::new(0), attrs); |
6a06907d | 562 | } |
dfeec247 | 563 | |
c295e0f8 | 564 | let item = hir::Item { |
2b03887a | 565 | owner_id: hir::OwnerId { def_id: new_hir_id }, |
94222f64 | 566 | ident: this.lower_ident(ident), |
dfeec247 | 567 | kind, |
04454e1e | 568 | vis_span, |
94222f64 | 569 | span: this.lower_span(use_tree.span), |
c295e0f8 XL |
570 | }; |
571 | hir::OwnerNode::Item(this.arena.alloc(item)) | |
416331ca XL |
572 | }); |
573 | } | |
574 | ||
487cf647 FG |
575 | let res = |
576 | self.expect_full_res_from_use(id).map(|res| self.lower_res(res)).collect(); | |
577 | let path = self.lower_use_path(res, &prefix, ParamMode::Explicit); | |
416331ca XL |
578 | hir::ItemKind::Use(path, hir::UseKind::ListStem) |
579 | } | |
580 | } | |
581 | } | |
582 | ||
c295e0f8 | 583 | fn lower_foreign_item(&mut self, i: &ForeignItem) -> &'hir hir::ForeignItem<'hir> { |
6a06907d | 584 | let hir_id = self.lower_node_id(i.id); |
2b03887a | 585 | let owner_id = hir_id.expect_owner(); |
6a06907d | 586 | self.lower_attrs(hir_id, &i.attrs); |
c295e0f8 | 587 | let item = hir::ForeignItem { |
2b03887a | 588 | owner_id, |
94222f64 | 589 | ident: self.lower_ident(i.ident), |
487cf647 FG |
590 | kind: match &i.kind { |
591 | ForeignItemKind::Fn(box Fn { sig, generics, .. }) => { | |
74b04a01 | 592 | let fdec = &sig.decl; |
9c376795 | 593 | let itctx = ImplTraitContext::Universal; |
04454e1e | 594 | let (generics, (fn_dec, fn_args)) = |
9c376795 | 595 | self.lower_generics(generics, i.id, &itctx, |this| { |
416331ca | 596 | ( |
e1599b0c | 597 | // Disallow `impl Trait` in foreign items. |
f2b60f7d FG |
598 | this.lower_fn_decl( |
599 | fdec, | |
487cf647 | 600 | i.id, |
f2b60f7d FG |
601 | sig.span, |
602 | FnDeclKind::ExternFn, | |
603 | None, | |
604 | ), | |
e1599b0c | 605 | this.lower_fn_params_to_names(fdec), |
416331ca | 606 | ) |
04454e1e | 607 | }); |
416331ca XL |
608 | |
609 | hir::ForeignItemKind::Fn(fn_dec, fn_args, generics) | |
610 | } | |
487cf647 | 611 | ForeignItemKind::Static(t, m, _) => { |
9ffffee4 FG |
612 | let ty = self |
613 | .lower_ty(t, &ImplTraitContext::Disallowed(ImplTraitPosition::StaticTy)); | |
487cf647 | 614 | hir::ForeignItemKind::Static(ty, *m) |
416331ca | 615 | } |
74b04a01 | 616 | ForeignItemKind::TyAlias(..) => hir::ForeignItemKind::Type, |
ba9703b0 | 617 | ForeignItemKind::MacCall(_) => panic!("macro shouldn't exist here"), |
416331ca | 618 | }, |
04454e1e | 619 | vis_span: self.lower_span(i.vis.span), |
94222f64 | 620 | span: self.lower_span(i.span), |
c295e0f8 XL |
621 | }; |
622 | self.arena.alloc(item) | |
416331ca XL |
623 | } |
624 | ||
c295e0f8 | 625 | fn lower_foreign_item_ref(&mut self, i: &ForeignItem) -> hir::ForeignItemRef { |
fc512014 | 626 | hir::ForeignItemRef { |
2b03887a | 627 | id: hir::ForeignItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } }, |
94222f64 XL |
628 | ident: self.lower_ident(i.ident), |
629 | span: self.lower_span(i.span), | |
416331ca XL |
630 | } |
631 | } | |
632 | ||
dfeec247 | 633 | fn lower_variant(&mut self, v: &Variant) -> hir::Variant<'hir> { |
487cf647 FG |
634 | let hir_id = self.lower_node_id(v.id); |
635 | self.lower_attrs(hir_id, &v.attrs); | |
e1599b0c | 636 | hir::Variant { |
487cf647 FG |
637 | hir_id, |
638 | def_id: self.local_def_id(v.id), | |
639 | data: self.lower_variant_data(hir_id, &v.data), | |
e1599b0c | 640 | disr_expr: v.disr_expr.as_ref().map(|e| self.lower_anon_const(e)), |
94222f64 XL |
641 | ident: self.lower_ident(v.ident), |
642 | span: self.lower_span(v.span), | |
416331ca XL |
643 | } |
644 | } | |
645 | ||
6a06907d XL |
646 | fn lower_variant_data( |
647 | &mut self, | |
648 | parent_id: hir::HirId, | |
649 | vdata: &VariantData, | |
650 | ) -> hir::VariantData<'hir> { | |
487cf647 FG |
651 | match vdata { |
652 | VariantData::Struct(fields, recovered) => hir::VariantData::Struct( | |
dfeec247 | 653 | self.arena |
6a06907d | 654 | .alloc_from_iter(fields.iter().enumerate().map(|f| self.lower_field_def(f))), |
487cf647 | 655 | *recovered, |
416331ca | 656 | ), |
487cf647 FG |
657 | VariantData::Tuple(fields, id) => { |
658 | let ctor_id = self.lower_node_id(*id); | |
6a06907d XL |
659 | self.alias_attrs(ctor_id, parent_id); |
660 | hir::VariantData::Tuple( | |
661 | self.arena.alloc_from_iter( | |
662 | fields.iter().enumerate().map(|f| self.lower_field_def(f)), | |
663 | ), | |
664 | ctor_id, | |
487cf647 | 665 | self.local_def_id(*id), |
6a06907d XL |
666 | ) |
667 | } | |
668 | VariantData::Unit(id) => { | |
487cf647 | 669 | let ctor_id = self.lower_node_id(*id); |
6a06907d | 670 | self.alias_attrs(ctor_id, parent_id); |
487cf647 | 671 | hir::VariantData::Unit(ctor_id, self.local_def_id(*id)) |
6a06907d | 672 | } |
416331ca XL |
673 | } |
674 | } | |
675 | ||
94222f64 | 676 | fn lower_field_def(&mut self, (index, f): (usize, &FieldDef)) -> hir::FieldDef<'hir> { |
487cf647 | 677 | let ty = if let TyKind::Path(qself, path) = &f.ty.kind { |
416331ca XL |
678 | let t = self.lower_path_ty( |
679 | &f.ty, | |
680 | qself, | |
681 | path, | |
682 | ParamMode::ExplicitNamed, // no `'_` in declarations (Issue #61124) | |
9ffffee4 | 683 | &ImplTraitContext::Disallowed(ImplTraitPosition::FieldTy), |
416331ca | 684 | ); |
dfeec247 | 685 | self.arena.alloc(t) |
416331ca | 686 | } else { |
9ffffee4 | 687 | self.lower_ty(&f.ty, &ImplTraitContext::Disallowed(ImplTraitPosition::FieldTy)) |
416331ca | 688 | }; |
6a06907d XL |
689 | let hir_id = self.lower_node_id(f.id); |
690 | self.lower_attrs(hir_id, &f.attrs); | |
691 | hir::FieldDef { | |
94222f64 | 692 | span: self.lower_span(f.span), |
6a06907d | 693 | hir_id, |
487cf647 | 694 | def_id: self.local_def_id(f.id), |
416331ca | 695 | ident: match f.ident { |
94222f64 | 696 | Some(ident) => self.lower_ident(ident), |
416331ca | 697 | // FIXME(jseyfried): positional field hygiene. |
94222f64 | 698 | None => Ident::new(sym::integer(index), self.lower_span(f.span)), |
416331ca | 699 | }, |
04454e1e | 700 | vis_span: self.lower_span(f.vis.span), |
416331ca | 701 | ty, |
416331ca XL |
702 | } |
703 | } | |
704 | ||
c295e0f8 | 705 | fn lower_trait_item(&mut self, i: &AssocItem) -> &'hir hir::TraitItem<'hir> { |
6a06907d | 706 | let hir_id = self.lower_node_id(i.id); |
487cf647 | 707 | self.lower_attrs(hir_id, &i.attrs); |
6a06907d | 708 | let trait_item_def_id = hir_id.expect_owner(); |
416331ca | 709 | |
487cf647 FG |
710 | let (generics, kind, has_default) = match &i.kind { |
711 | AssocItemKind::Const(_, ty, default) => { | |
9ffffee4 FG |
712 | let ty = |
713 | self.lower_ty(ty, &ImplTraitContext::Disallowed(ImplTraitPosition::ConstTy)); | |
74b04a01 | 714 | let body = default.as_ref().map(|x| self.lower_const_body(i.span, Some(x))); |
064997fb | 715 | (hir::Generics::empty(), hir::TraitItemKind::Const(ty, body), body.is_some()) |
dfeec247 | 716 | } |
487cf647 | 717 | AssocItemKind::Fn(box Fn { sig, generics, body: None, .. }) => { |
f2b60f7d | 718 | let asyncness = sig.header.asyncness; |
e1599b0c | 719 | let names = self.lower_fn_params_to_names(&sig.decl); |
f2b60f7d FG |
720 | let (generics, sig) = self.lower_method_sig( |
721 | generics, | |
722 | sig, | |
723 | i.id, | |
724 | FnDeclKind::Trait, | |
725 | asyncness.opt_return_id(), | |
726 | ); | |
064997fb | 727 | (generics, hir::TraitItemKind::Fn(sig, hir::TraitFn::Required(names)), false) |
416331ca | 728 | } |
487cf647 | 729 | AssocItemKind::Fn(box Fn { sig, generics, body: Some(body), .. }) => { |
cdc7bbd5 XL |
730 | let asyncness = sig.header.asyncness; |
731 | let body_id = | |
487cf647 | 732 | self.lower_maybe_async_body(i.span, hir_id, &sig.decl, asyncness, Some(&body)); |
cdc7bbd5 XL |
733 | let (generics, sig) = self.lower_method_sig( |
734 | generics, | |
735 | sig, | |
04454e1e | 736 | i.id, |
5099ac24 | 737 | FnDeclKind::Trait, |
cdc7bbd5 | 738 | asyncness.opt_return_id(), |
cdc7bbd5 | 739 | ); |
064997fb | 740 | (generics, hir::TraitItemKind::Fn(sig, hir::TraitFn::Provided(body_id)), true) |
416331ca | 741 | } |
487cf647 | 742 | AssocItemKind::Type(box TyAlias { generics, where_clauses, bounds, ty, .. }) => { |
5e7ed085 | 743 | let mut generics = generics.clone(); |
487cf647 | 744 | add_ty_alias_where_clause(&mut generics, *where_clauses, false); |
064997fb | 745 | let (generics, kind) = self.lower_generics( |
5e7ed085 | 746 | &generics, |
923072b8 | 747 | i.id, |
f2b60f7d | 748 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
749 | |this| { |
750 | let ty = ty.as_ref().map(|x| { | |
9ffffee4 FG |
751 | this.lower_ty( |
752 | x, | |
753 | &ImplTraitContext::Disallowed(ImplTraitPosition::AssocTy), | |
754 | ) | |
923072b8 FG |
755 | }); |
756 | hir::TraitItemKind::Type( | |
757 | this.lower_param_bounds( | |
758 | bounds, | |
f2b60f7d | 759 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
760 | ), |
761 | ty, | |
762 | ) | |
763 | }, | |
064997fb FG |
764 | ); |
765 | (generics, kind, ty.is_some()) | |
dfeec247 | 766 | } |
ba9703b0 | 767 | AssocItemKind::MacCall(..) => panic!("macro item shouldn't exist at this point"), |
416331ca XL |
768 | }; |
769 | ||
c295e0f8 | 770 | let item = hir::TraitItem { |
2b03887a | 771 | owner_id: trait_item_def_id, |
94222f64 XL |
772 | ident: self.lower_ident(i.ident), |
773 | generics, | |
774 | kind, | |
775 | span: self.lower_span(i.span), | |
064997fb | 776 | defaultness: hir::Defaultness::Default { has_value: has_default }, |
c295e0f8 XL |
777 | }; |
778 | self.arena.alloc(item) | |
416331ca XL |
779 | } |
780 | ||
dfeec247 | 781 | fn lower_trait_item_ref(&mut self, i: &AssocItem) -> hir::TraitItemRef { |
064997fb FG |
782 | let kind = match &i.kind { |
783 | AssocItemKind::Const(..) => hir::AssocItemKind::Const, | |
2b03887a | 784 | AssocItemKind::Type(..) => hir::AssocItemKind::Type, |
064997fb FG |
785 | AssocItemKind::Fn(box Fn { sig, .. }) => { |
786 | hir::AssocItemKind::Fn { has_self: sig.decl.has_self() } | |
416331ca | 787 | } |
ba9703b0 | 788 | AssocItemKind::MacCall(..) => unimplemented!(), |
416331ca | 789 | }; |
2b03887a | 790 | let id = hir::TraitItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } }; |
94222f64 XL |
791 | hir::TraitItemRef { |
792 | id, | |
793 | ident: self.lower_ident(i.ident), | |
794 | span: self.lower_span(i.span), | |
94222f64 XL |
795 | kind, |
796 | } | |
416331ca XL |
797 | } |
798 | ||
dfeec247 | 799 | /// Construct `ExprKind::Err` for the given `span`. |
9ffffee4 FG |
800 | pub(crate) fn expr_err(&mut self, span: Span, guar: ErrorGuaranteed) -> hir::Expr<'hir> { |
801 | self.expr(span, hir::ExprKind::Err(guar)) | |
dfeec247 XL |
802 | } |
803 | ||
c295e0f8 | 804 | fn lower_impl_item(&mut self, i: &AssocItem) -> &'hir hir::ImplItem<'hir> { |
064997fb FG |
805 | // Since `default impl` is not yet implemented, this is always true in impls. |
806 | let has_value = true; | |
807 | let (defaultness, _) = self.lower_defaultness(i.kind.defaultness(), has_value); | |
487cf647 FG |
808 | let hir_id = self.lower_node_id(i.id); |
809 | self.lower_attrs(hir_id, &i.attrs); | |
064997fb | 810 | |
74b04a01 XL |
811 | let (generics, kind) = match &i.kind { |
812 | AssocItemKind::Const(_, ty, expr) => { | |
9ffffee4 FG |
813 | let ty = |
814 | self.lower_ty(ty, &ImplTraitContext::Disallowed(ImplTraitPosition::ConstTy)); | |
dfeec247 | 815 | ( |
74b04a01 | 816 | hir::Generics::empty(), |
dfeec247 XL |
817 | hir::ImplItemKind::Const(ty, self.lower_const_body(i.span, expr.as_deref())), |
818 | ) | |
819 | } | |
3c0e092e | 820 | AssocItemKind::Fn(box Fn { sig, generics, body, .. }) => { |
416331ca | 821 | self.current_item = Some(i.span); |
74b04a01 | 822 | let asyncness = sig.header.asyncness; |
487cf647 FG |
823 | let body_id = self.lower_maybe_async_body( |
824 | i.span, | |
825 | hir_id, | |
826 | &sig.decl, | |
827 | asyncness, | |
828 | body.as_deref(), | |
829 | ); | |
416331ca | 830 | let (generics, sig) = self.lower_method_sig( |
74b04a01 | 831 | generics, |
416331ca | 832 | sig, |
04454e1e | 833 | i.id, |
5099ac24 | 834 | if self.is_in_trait_impl { FnDeclKind::Impl } else { FnDeclKind::Inherent }, |
74b04a01 | 835 | asyncness.opt_return_id(), |
416331ca XL |
836 | ); |
837 | ||
ba9703b0 | 838 | (generics, hir::ImplItemKind::Fn(sig, body_id)) |
416331ca | 839 | } |
2b03887a | 840 | AssocItemKind::Type(box TyAlias { generics, where_clauses, ty, .. }) => { |
5e7ed085 FG |
841 | let mut generics = generics.clone(); |
842 | add_ty_alias_where_clause(&mut generics, *where_clauses, false); | |
923072b8 | 843 | self.lower_generics( |
5e7ed085 | 844 | &generics, |
923072b8 | 845 | i.id, |
f2b60f7d | 846 | &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |
923072b8 FG |
847 | |this| match ty { |
848 | None => { | |
9ffffee4 FG |
849 | let guar = this.tcx.sess.delay_span_bug( |
850 | i.span, | |
851 | "expected to lower associated type, but it was missing", | |
852 | ); | |
853 | let ty = this.arena.alloc(this.ty(i.span, hir::TyKind::Err(guar))); | |
2b03887a | 854 | hir::ImplItemKind::Type(ty) |
923072b8 FG |
855 | } |
856 | Some(ty) => { | |
f2b60f7d | 857 | let ty = this.lower_ty(ty, &ImplTraitContext::TypeAliasesOpaqueTy); |
2b03887a | 858 | hir::ImplItemKind::Type(ty) |
923072b8 FG |
859 | } |
860 | }, | |
861 | ) | |
dfeec247 | 862 | } |
ba9703b0 | 863 | AssocItemKind::MacCall(..) => panic!("`TyMac` should have been expanded by now"), |
416331ca XL |
864 | }; |
865 | ||
c295e0f8 | 866 | let item = hir::ImplItem { |
2b03887a | 867 | owner_id: hir_id.expect_owner(), |
94222f64 | 868 | ident: self.lower_ident(i.ident), |
416331ca | 869 | generics, |
e74abb32 | 870 | kind, |
04454e1e | 871 | vis_span: self.lower_span(i.vis.span), |
94222f64 | 872 | span: self.lower_span(i.span), |
064997fb | 873 | defaultness, |
c295e0f8 XL |
874 | }; |
875 | self.arena.alloc(item) | |
416331ca XL |
876 | } |
877 | ||
c295e0f8 | 878 | fn lower_impl_item_ref(&mut self, i: &AssocItem) -> hir::ImplItemRef { |
416331ca | 879 | hir::ImplItemRef { |
2b03887a | 880 | id: hir::ImplItemId { owner_id: hir::OwnerId { def_id: self.local_def_id(i.id) } }, |
94222f64 XL |
881 | ident: self.lower_ident(i.ident), |
882 | span: self.lower_span(i.span), | |
60c5eb7d | 883 | kind: match &i.kind { |
dfeec247 | 884 | AssocItemKind::Const(..) => hir::AssocItemKind::Const, |
2b03887a | 885 | AssocItemKind::Type(..) => hir::AssocItemKind::Type, |
3c0e092e | 886 | AssocItemKind::Fn(box Fn { sig, .. }) => { |
ba9703b0 | 887 | hir::AssocItemKind::Fn { has_self: sig.decl.has_self() } |
dfeec247 | 888 | } |
ba9703b0 | 889 | AssocItemKind::MacCall(..) => unimplemented!(), |
416331ca | 890 | }, |
2b03887a FG |
891 | trait_item_def_id: self |
892 | .resolver | |
893 | .get_partial_res(i.id) | |
894 | .map(|r| r.expect_full_res().def_id()), | |
416331ca | 895 | } |
416331ca XL |
896 | } |
897 | ||
ba9703b0 XL |
898 | fn lower_defaultness( |
899 | &self, | |
900 | d: Defaultness, | |
901 | has_value: bool, | |
902 | ) -> (hir::Defaultness, Option<Span>) { | |
416331ca | 903 | match d { |
94222f64 XL |
904 | Defaultness::Default(sp) => { |
905 | (hir::Defaultness::Default { has_value }, Some(self.lower_span(sp))) | |
906 | } | |
416331ca XL |
907 | Defaultness::Final => { |
908 | assert!(has_value); | |
ba9703b0 | 909 | (hir::Defaultness::Final, None) |
416331ca XL |
910 | } |
911 | } | |
912 | } | |
913 | ||
dfeec247 XL |
914 | fn record_body( |
915 | &mut self, | |
916 | params: &'hir [hir::Param<'hir>], | |
917 | value: hir::Expr<'hir>, | |
918 | ) -> hir::BodyId { | |
f2b60f7d FG |
919 | let body = hir::Body { |
920 | generator_kind: self.generator_kind, | |
921 | params, | |
922 | value: self.arena.alloc(value), | |
923 | }; | |
416331ca | 924 | let id = body.id(); |
3c0e092e XL |
925 | debug_assert_eq!(id.hir_id.owner, self.current_hir_id_owner); |
926 | self.bodies.push((id.hir_id.local_id, self.arena.alloc(body))); | |
416331ca XL |
927 | id |
928 | } | |
929 | ||
ba9703b0 | 930 | pub(super) fn lower_body( |
416331ca | 931 | &mut self, |
dfeec247 | 932 | f: impl FnOnce(&mut Self) -> (&'hir [hir::Param<'hir>], hir::Expr<'hir>), |
416331ca XL |
933 | ) -> hir::BodyId { |
934 | let prev_gen_kind = self.generator_kind.take(); | |
ba9703b0 | 935 | let task_context = self.task_context.take(); |
e1599b0c XL |
936 | let (parameters, result) = f(self); |
937 | let body_id = self.record_body(parameters, result); | |
ba9703b0 | 938 | self.task_context = task_context; |
416331ca XL |
939 | self.generator_kind = prev_gen_kind; |
940 | body_id | |
941 | } | |
942 | ||
dfeec247 | 943 | fn lower_param(&mut self, param: &Param) -> hir::Param<'hir> { |
6a06907d XL |
944 | let hir_id = self.lower_node_id(param.id); |
945 | self.lower_attrs(hir_id, ¶m.attrs); | |
e1599b0c | 946 | hir::Param { |
6a06907d | 947 | hir_id, |
e1599b0c | 948 | pat: self.lower_pat(¶m.pat), |
94222f64 XL |
949 | ty_span: self.lower_span(param.ty.span), |
950 | span: self.lower_span(param.span), | |
416331ca XL |
951 | } |
952 | } | |
953 | ||
954 | pub(super) fn lower_fn_body( | |
955 | &mut self, | |
956 | decl: &FnDecl, | |
dfeec247 | 957 | body: impl FnOnce(&mut Self) -> hir::Expr<'hir>, |
416331ca | 958 | ) -> hir::BodyId { |
dfeec247 XL |
959 | self.lower_body(|this| { |
960 | ( | |
961 | this.arena.alloc_from_iter(decl.inputs.iter().map(|x| this.lower_param(x))), | |
962 | body(this), | |
963 | ) | |
964 | }) | |
416331ca XL |
965 | } |
966 | ||
dfeec247 XL |
967 | fn lower_fn_body_block( |
968 | &mut self, | |
969 | span: Span, | |
970 | decl: &FnDecl, | |
971 | body: Option<&Block>, | |
972 | ) -> hir::BodyId { | |
973 | self.lower_fn_body(decl, |this| this.lower_block_expr_opt(span, body)) | |
416331ca XL |
974 | } |
975 | ||
dfeec247 XL |
976 | fn lower_block_expr_opt(&mut self, span: Span, block: Option<&Block>) -> hir::Expr<'hir> { |
977 | match block { | |
978 | Some(block) => self.lower_block_expr(block), | |
9ffffee4 | 979 | None => self.expr_err(span, self.tcx.sess.delay_span_bug(span, "no block")), |
dfeec247 XL |
980 | } |
981 | } | |
982 | ||
983 | pub(super) fn lower_const_body(&mut self, span: Span, expr: Option<&Expr>) -> hir::BodyId { | |
984 | self.lower_body(|this| { | |
985 | ( | |
986 | &[], | |
987 | match expr { | |
988 | Some(expr) => this.lower_expr_mut(expr), | |
9ffffee4 | 989 | None => this.expr_err(span, this.tcx.sess.delay_span_bug(span, "no block")), |
dfeec247 XL |
990 | }, |
991 | ) | |
992 | }) | |
416331ca XL |
993 | } |
994 | ||
995 | fn lower_maybe_async_body( | |
996 | &mut self, | |
dfeec247 | 997 | span: Span, |
487cf647 | 998 | fn_id: hir::HirId, |
416331ca | 999 | decl: &FnDecl, |
74b04a01 | 1000 | asyncness: Async, |
dfeec247 | 1001 | body: Option<&Block>, |
416331ca | 1002 | ) -> hir::BodyId { |
2b03887a FG |
1003 | let (closure_id, body) = match (asyncness, body) { |
1004 | (Async::Yes { closure_id, .. }, Some(body)) => (closure_id, body), | |
1005 | _ => return self.lower_fn_body_block(span, decl, body), | |
416331ca XL |
1006 | }; |
1007 | ||
1008 | self.lower_body(|this| { | |
dfeec247 XL |
1009 | let mut parameters: Vec<hir::Param<'_>> = Vec::new(); |
1010 | let mut statements: Vec<hir::Stmt<'_>> = Vec::new(); | |
416331ca | 1011 | |
e1599b0c | 1012 | // Async function parameters are lowered into the closure body so that they are |
416331ca XL |
1013 | // captured and so that the drop order matches the equivalent non-async functions. |
1014 | // | |
1015 | // from: | |
1016 | // | |
1017 | // async fn foo(<pattern>: <ty>, <pattern>: <ty>, <pattern>: <ty>) { | |
e1599b0c | 1018 | // <body> |
416331ca XL |
1019 | // } |
1020 | // | |
1021 | // into: | |
1022 | // | |
1023 | // fn foo(__arg0: <ty>, __arg1: <ty>, __arg2: <ty>) { | |
1024 | // async move { | |
1025 | // let __arg2 = __arg2; | |
1026 | // let <pattern> = __arg2; | |
1027 | // let __arg1 = __arg1; | |
1028 | // let <pattern> = __arg1; | |
1029 | // let __arg0 = __arg0; | |
1030 | // let <pattern> = __arg0; | |
e1599b0c | 1031 | // drop-temps { <body> } // see comments later in fn for details |
416331ca XL |
1032 | // } |
1033 | // } | |
1034 | // | |
1035 | // If `<pattern>` is a simple ident, then it is lowered to a single | |
1036 | // `let <pattern> = <pattern>;` statement as an optimization. | |
e1599b0c XL |
1037 | // |
1038 | // Note that the body is embedded in `drop-temps`; an | |
1039 | // equivalent desugaring would be `return { <body> | |
1040 | // };`. The key point is that we wish to drop all the | |
1041 | // let-bound variables and temporaries created in the body | |
1042 | // (and its tail expression!) before we drop the | |
1043 | // parameters (c.f. rust-lang/rust#64512). | |
1044 | for (index, parameter) in decl.inputs.iter().enumerate() { | |
1045 | let parameter = this.lower_param(parameter); | |
1046 | let span = parameter.pat.span; | |
416331ca XL |
1047 | |
1048 | // Check if this is a binding pattern, if so, we can optimize and avoid adding a | |
e1599b0c | 1049 | // `let <pat> = __argN;` statement. In this case, we do not rename the parameter. |
e74abb32 | 1050 | let (ident, is_simple_parameter) = match parameter.pat.kind { |
f2b60f7d FG |
1051 | hir::PatKind::Binding(hir::BindingAnnotation(ByRef::No, _), _, ident, _) => { |
1052 | (ident, true) | |
1053 | } | |
29967ef6 XL |
1054 | // For `ref mut` or wildcard arguments, we can't reuse the binding, but |
1055 | // we can keep the same name for the parameter. | |
1056 | // This lets rustdoc render it correctly in documentation. | |
1057 | hir::PatKind::Binding(_, _, ident, _) => (ident, false), | |
1058 | hir::PatKind::Wild => { | |
1059 | (Ident::with_dummy_span(rustc_span::symbol::kw::Underscore), false) | |
dfeec247 | 1060 | } |
416331ca XL |
1061 | _ => { |
1062 | // Replace the ident for bindings that aren't simple. | |
9c376795 | 1063 | let name = format!("__arg{index}"); |
416331ca XL |
1064 | let ident = Ident::from_str(&name); |
1065 | ||
1066 | (ident, false) | |
dfeec247 | 1067 | } |
416331ca XL |
1068 | }; |
1069 | ||
dfeec247 | 1070 | let desugared_span = this.mark_span_with_reason(DesugaringKind::Async, span, None); |
416331ca | 1071 | |
e1599b0c | 1072 | // Construct a parameter representing `__argN: <ty>` to replace the parameter of the |
416331ca XL |
1073 | // async function. |
1074 | // | |
e1599b0c XL |
1075 | // If this is the simple case, this parameter will end up being the same as the |
1076 | // original parameter, but with a different pattern id. | |
3c0e092e | 1077 | let stmt_attrs = this.attrs.get(¶meter.hir_id.local_id).copied(); |
e1599b0c XL |
1078 | let (new_parameter_pat, new_parameter_id) = this.pat_ident(desugared_span, ident); |
1079 | let new_parameter = hir::Param { | |
e1599b0c XL |
1080 | hir_id: parameter.hir_id, |
1081 | pat: new_parameter_pat, | |
94222f64 XL |
1082 | ty_span: this.lower_span(parameter.ty_span), |
1083 | span: this.lower_span(parameter.span), | |
416331ca XL |
1084 | }; |
1085 | ||
e1599b0c | 1086 | if is_simple_parameter { |
416331ca XL |
1087 | // If this is the simple case, then we only insert one statement that is |
1088 | // `let <pat> = <pat>;`. We re-use the original argument's pattern so that | |
1089 | // `HirId`s are densely assigned. | |
e1599b0c | 1090 | let expr = this.expr_ident(desugared_span, ident, new_parameter_id); |
416331ca XL |
1091 | let stmt = this.stmt_let_pat( |
1092 | stmt_attrs, | |
1093 | desugared_span, | |
dfeec247 | 1094 | Some(expr), |
e1599b0c | 1095 | parameter.pat, |
dfeec247 | 1096 | hir::LocalSource::AsyncFn, |
416331ca XL |
1097 | ); |
1098 | statements.push(stmt); | |
1099 | } else { | |
1100 | // If this is not the simple case, then we construct two statements: | |
1101 | // | |
1102 | // ``` | |
1103 | // let __argN = __argN; | |
1104 | // let <pat> = __argN; | |
1105 | // ``` | |
1106 | // | |
e1599b0c | 1107 | // The first statement moves the parameter into the closure and thus ensures |
416331ca XL |
1108 | // that the drop order is correct. |
1109 | // | |
1110 | // The second statement creates the bindings that the user wrote. | |
1111 | ||
1112 | // Construct the `let mut __argN = __argN;` statement. It must be a mut binding | |
1113 | // because the user may have specified a `ref mut` binding in the next | |
1114 | // statement. | |
1115 | let (move_pat, move_id) = this.pat_ident_binding_mode( | |
dfeec247 XL |
1116 | desugared_span, |
1117 | ident, | |
f2b60f7d | 1118 | hir::BindingAnnotation::MUT, |
dfeec247 | 1119 | ); |
e1599b0c | 1120 | let move_expr = this.expr_ident(desugared_span, ident, new_parameter_id); |
416331ca | 1121 | let move_stmt = this.stmt_let_pat( |
6a06907d | 1122 | None, |
416331ca | 1123 | desugared_span, |
dfeec247 | 1124 | Some(move_expr), |
416331ca | 1125 | move_pat, |
dfeec247 | 1126 | hir::LocalSource::AsyncFn, |
416331ca XL |
1127 | ); |
1128 | ||
1129 | // Construct the `let <pat> = __argN;` statement. We re-use the original | |
e1599b0c | 1130 | // parameter's pattern so that `HirId`s are densely assigned. |
416331ca XL |
1131 | let pattern_expr = this.expr_ident(desugared_span, ident, move_id); |
1132 | let pattern_stmt = this.stmt_let_pat( | |
1133 | stmt_attrs, | |
1134 | desugared_span, | |
dfeec247 | 1135 | Some(pattern_expr), |
e1599b0c | 1136 | parameter.pat, |
dfeec247 | 1137 | hir::LocalSource::AsyncFn, |
416331ca XL |
1138 | ); |
1139 | ||
1140 | statements.push(move_stmt); | |
1141 | statements.push(pattern_stmt); | |
1142 | }; | |
1143 | ||
e1599b0c | 1144 | parameters.push(new_parameter); |
416331ca XL |
1145 | } |
1146 | ||
1147 | let async_expr = this.make_async_expr( | |
e74abb32 | 1148 | CaptureBy::Value, |
9c376795 | 1149 | fn_id, |
e74abb32 XL |
1150 | closure_id, |
1151 | None, | |
2b03887a | 1152 | body.span, |
e74abb32 | 1153 | hir::AsyncGeneratorKind::Fn, |
416331ca | 1154 | |this| { |
e1599b0c | 1155 | // Create a block from the user's function body: |
2b03887a | 1156 | let user_body = this.lower_block_expr(body); |
e1599b0c XL |
1157 | |
1158 | // Transform into `drop-temps { <user-body> }`, an expression: | |
dfeec247 XL |
1159 | let desugared_span = |
1160 | this.mark_span_with_reason(DesugaringKind::Async, user_body.span, None); | |
487cf647 FG |
1161 | let user_body = |
1162 | this.expr_drop_temps(desugared_span, this.arena.alloc(user_body)); | |
e1599b0c XL |
1163 | |
1164 | // As noted above, create the final block like | |
1165 | // | |
1166 | // ``` | |
1167 | // { | |
1168 | // let $param_pattern = $raw_param; | |
1169 | // ... | |
1170 | // drop-temps { <user-body> } | |
1171 | // } | |
1172 | // ``` | |
1173 | let body = this.block_all( | |
1174 | desugared_span, | |
dfeec247 XL |
1175 | this.arena.alloc_from_iter(statements), |
1176 | Some(user_body), | |
e1599b0c | 1177 | ); |
dfeec247 | 1178 | |
487cf647 | 1179 | this.expr_block(body) |
dfeec247 XL |
1180 | }, |
1181 | ); | |
1182 | ||
487cf647 | 1183 | (this.arena.alloc_from_iter(parameters), this.expr(body.span, async_expr)) |
416331ca XL |
1184 | }) |
1185 | } | |
1186 | ||
1187 | fn lower_method_sig( | |
1188 | &mut self, | |
1189 | generics: &Generics, | |
60c5eb7d | 1190 | sig: &FnSig, |
04454e1e | 1191 | id: NodeId, |
5099ac24 | 1192 | kind: FnDeclKind, |
f2b60f7d | 1193 | is_async: Option<(NodeId, Span)>, |
04454e1e | 1194 | ) -> (&'hir hir::Generics<'hir>, hir::FnSig<'hir>) { |
94222f64 | 1195 | let header = self.lower_fn_header(sig.header); |
9c376795 FG |
1196 | let itctx = ImplTraitContext::Universal; |
1197 | let (generics, decl) = self.lower_generics(generics, id, &itctx, |this| { | |
487cf647 | 1198 | this.lower_fn_decl(&sig.decl, id, sig.span, kind, is_async) |
04454e1e | 1199 | }); |
94222f64 | 1200 | (generics, hir::FnSig { header, decl, span: self.lower_span(sig.span) }) |
416331ca XL |
1201 | } |
1202 | ||
94222f64 | 1203 | fn lower_fn_header(&mut self, h: FnHeader) -> hir::FnHeader { |
416331ca | 1204 | hir::FnHeader { |
74b04a01 XL |
1205 | unsafety: self.lower_unsafety(h.unsafety), |
1206 | asyncness: self.lower_asyncness(h.asyncness), | |
1207 | constness: self.lower_constness(h.constness), | |
94222f64 | 1208 | abi: self.lower_extern(h.ext), |
416331ca XL |
1209 | } |
1210 | } | |
1211 | ||
60c5eb7d | 1212 | pub(super) fn lower_abi(&mut self, abi: StrLit) -> abi::Abi { |
a2a8927a | 1213 | abi::lookup(abi.symbol_unescaped.as_str()).unwrap_or_else(|| { |
60c5eb7d XL |
1214 | self.error_on_invalid_abi(abi); |
1215 | abi::Abi::Rust | |
1216 | }) | |
416331ca XL |
1217 | } |
1218 | ||
94222f64 | 1219 | pub(super) fn lower_extern(&mut self, ext: Extern) -> abi::Abi { |
60c5eb7d XL |
1220 | match ext { |
1221 | Extern::None => abi::Abi::Rust, | |
064997fb FG |
1222 | Extern::Implicit(_) => abi::Abi::FALLBACK, |
1223 | Extern::Explicit(abi, _) => self.lower_abi(abi), | |
416331ca XL |
1224 | } |
1225 | } | |
1226 | ||
60c5eb7d | 1227 | fn error_on_invalid_abi(&self, abi: StrLit) { |
2b03887a FG |
1228 | let abi_names = abi::enabled_names(self.tcx.features(), abi.span) |
1229 | .iter() | |
1230 | .map(|s| Symbol::intern(s)) | |
1231 | .collect::<Vec<_>>(); | |
1232 | let suggested_name = find_best_match_for_name(&abi_names, abi.symbol_unescaped, None); | |
f2b60f7d | 1233 | self.tcx.sess.emit_err(InvalidAbi { |
2b03887a | 1234 | abi: abi.symbol_unescaped, |
f2b60f7d | 1235 | span: abi.span, |
2b03887a FG |
1236 | suggestion: suggested_name.map(|suggested_name| InvalidAbiSuggestion { |
1237 | span: abi.span, | |
1238 | suggestion: format!("\"{suggested_name}\""), | |
1239 | }), | |
1240 | command: "rustc --print=calling-conventions".to_string(), | |
f2b60f7d | 1241 | }); |
60c5eb7d XL |
1242 | } |
1243 | ||
74b04a01 | 1244 | fn lower_asyncness(&mut self, a: Async) -> hir::IsAsync { |
416331ca | 1245 | match a { |
74b04a01 XL |
1246 | Async::Yes { .. } => hir::IsAsync::Async, |
1247 | Async::No => hir::IsAsync::NotAsync, | |
1248 | } | |
1249 | } | |
1250 | ||
9c376795 | 1251 | pub(super) fn lower_constness(&mut self, c: Const) -> hir::Constness { |
74b04a01 XL |
1252 | match c { |
1253 | Const::Yes(_) => hir::Constness::Const, | |
1254 | Const::No => hir::Constness::NotConst, | |
1255 | } | |
1256 | } | |
1257 | ||
1258 | pub(super) fn lower_unsafety(&mut self, u: Unsafe) -> hir::Unsafety { | |
1259 | match u { | |
1260 | Unsafe::Yes(_) => hir::Unsafety::Unsafe, | |
1261 | Unsafe::No => hir::Unsafety::Normal, | |
416331ca XL |
1262 | } |
1263 | } | |
1264 | ||
923072b8 FG |
1265 | /// Return the pair of the lowered `generics` as `hir::Generics` and the evaluation of `f` with |
1266 | /// the carried impl trait definitions and bounds. | |
1267 | #[instrument(level = "debug", skip(self, f))] | |
1268 | fn lower_generics<T>( | |
416331ca XL |
1269 | &mut self, |
1270 | generics: &Generics, | |
923072b8 | 1271 | parent_node_id: NodeId, |
f2b60f7d | 1272 | itctx: &ImplTraitContext, |
923072b8 FG |
1273 | f: impl FnOnce(&mut Self) -> T, |
1274 | ) -> (&'hir hir::Generics<'hir>, T) { | |
1275 | debug_assert!(self.impl_trait_defs.is_empty()); | |
1276 | debug_assert!(self.impl_trait_bounds.is_empty()); | |
1277 | ||
5e7ed085 | 1278 | // Error if `?Trait` bounds in where clauses don't refer directly to type parameters. |
c295e0f8 XL |
1279 | // Note: we used to clone these bounds directly onto the type parameter (and avoid lowering |
1280 | // these into hir when we lower thee where clauses), but this makes it quite difficult to | |
1281 | // keep track of the Span info. Now, `add_implicitly_sized` in `AstConv` checks both param bounds and | |
1282 | // where clauses for `?Sized`. | |
416331ca | 1283 | for pred in &generics.where_clause.predicates { |
487cf647 | 1284 | let WherePredicate::BoundPredicate(bound_pred) = pred else { |
5e7ed085 | 1285 | continue; |
c295e0f8 XL |
1286 | }; |
1287 | let compute_is_param = || { | |
1288 | // Check if the where clause type is a plain type parameter. | |
1289 | match self | |
1290 | .resolver | |
1291 | .get_partial_res(bound_pred.bounded_ty.id) | |
2b03887a | 1292 | .and_then(|r| r.full_res()) |
c295e0f8 | 1293 | { |
2b03887a | 1294 | Some(Res::Def(DefKind::TyParam, def_id)) |
c295e0f8 XL |
1295 | if bound_pred.bound_generic_params.is_empty() => |
1296 | { | |
1297 | generics | |
1298 | .params | |
1299 | .iter() | |
923072b8 | 1300 | .any(|p| def_id == self.local_def_id(p.id).to_def_id()) |
416331ca | 1301 | } |
c295e0f8 XL |
1302 | // Either the `bounded_ty` is not a plain type parameter, or |
1303 | // it's not found in the generic type parameters list. | |
1304 | _ => false, | |
1305 | } | |
1306 | }; | |
1307 | // We only need to compute this once per `WherePredicate`, but don't | |
1308 | // need to compute this at all unless there is a Maybe bound. | |
1309 | let mut is_param: Option<bool> = None; | |
1310 | for bound in &bound_pred.bounds { | |
1311 | if !matches!(*bound, GenericBound::Trait(_, TraitBoundModifier::Maybe)) { | |
1312 | continue; | |
1313 | } | |
1314 | let is_param = *is_param.get_or_insert_with(compute_is_param); | |
1315 | if !is_param { | |
f2b60f7d | 1316 | self.tcx.sess.emit_err(MisplacedRelaxTraitBound { span: bound.span() }); |
416331ca XL |
1317 | } |
1318 | } | |
1319 | } | |
1320 | ||
923072b8 | 1321 | let mut predicates: SmallVec<[hir::WherePredicate<'hir>; 4]> = SmallVec::new(); |
04454e1e | 1322 | predicates.extend(generics.params.iter().filter_map(|param| { |
04454e1e FG |
1323 | self.lower_generic_bound_predicate( |
1324 | param.ident, | |
1325 | param.id, | |
1326 | ¶m.kind, | |
064997fb | 1327 | ¶m.bounds, |
9c376795 FG |
1328 | param.colon_span, |
1329 | generics.span, | |
064997fb | 1330 | itctx, |
04454e1e FG |
1331 | PredicateOrigin::GenericParam, |
1332 | ) | |
1333 | })); | |
1334 | predicates.extend( | |
1335 | generics | |
1336 | .where_clause | |
1337 | .predicates | |
1338 | .iter() | |
1339 | .map(|predicate| self.lower_where_predicate(predicate)), | |
1340 | ); | |
1341 | ||
9ffffee4 FG |
1342 | let mut params: SmallVec<[hir::GenericParam<'hir>; 4]> = self |
1343 | .lower_generic_params_mut(&generics.params, hir::GenericParamSource::Generics) | |
1344 | .collect(); | |
416331ca | 1345 | |
923072b8 FG |
1346 | // Introduce extra lifetimes if late resolution tells us to. |
1347 | let extra_lifetimes = self.resolver.take_extra_lifetime_params(parent_node_id); | |
1348 | params.extend(extra_lifetimes.into_iter().filter_map(|(ident, node_id, res)| { | |
9ffffee4 FG |
1349 | self.lifetime_res_to_generic_param( |
1350 | ident, | |
1351 | node_id, | |
1352 | res, | |
1353 | hir::GenericParamSource::Generics, | |
1354 | ) | |
923072b8 FG |
1355 | })); |
1356 | ||
1357 | let has_where_clause_predicates = !generics.where_clause.predicates.is_empty(); | |
1358 | let where_clause_span = self.lower_span(generics.where_clause.span); | |
1359 | let span = self.lower_span(generics.span); | |
1360 | let res = f(self); | |
1361 | ||
1362 | let impl_trait_defs = std::mem::take(&mut self.impl_trait_defs); | |
1363 | params.extend(impl_trait_defs.into_iter()); | |
1364 | ||
1365 | let impl_trait_bounds = std::mem::take(&mut self.impl_trait_bounds); | |
1366 | predicates.extend(impl_trait_bounds.into_iter()); | |
1367 | ||
1368 | let lowered_generics = self.arena.alloc(hir::Generics { | |
1369 | params: self.arena.alloc_from_iter(params), | |
1370 | predicates: self.arena.alloc_from_iter(predicates), | |
1371 | has_where_clause_predicates, | |
1372 | where_clause_span, | |
1373 | span, | |
1374 | }); | |
1375 | ||
1376 | (lowered_generics, res) | |
dfeec247 XL |
1377 | } |
1378 | ||
04454e1e FG |
1379 | pub(super) fn lower_generic_bound_predicate( |
1380 | &mut self, | |
1381 | ident: Ident, | |
1382 | id: NodeId, | |
1383 | kind: &GenericParamKind, | |
064997fb | 1384 | bounds: &[GenericBound], |
9c376795 FG |
1385 | colon_span: Option<Span>, |
1386 | parent_span: Span, | |
f2b60f7d | 1387 | itctx: &ImplTraitContext, |
04454e1e FG |
1388 | origin: PredicateOrigin, |
1389 | ) -> Option<hir::WherePredicate<'hir>> { | |
1390 | // Do not create a clause if we do not have anything inside it. | |
1391 | if bounds.is_empty() { | |
1392 | return None; | |
1393 | } | |
064997fb FG |
1394 | |
1395 | let bounds = self.lower_param_bounds(bounds, itctx); | |
1396 | ||
04454e1e FG |
1397 | let ident = self.lower_ident(ident); |
1398 | let param_span = ident.span; | |
9c376795 FG |
1399 | |
1400 | // Reconstruct the span of the entire predicate from the individual generic bounds. | |
1401 | let span_start = colon_span.unwrap_or_else(|| param_span.shrink_to_hi()); | |
1402 | let span = bounds.iter().fold(span_start, |span_accum, bound| { | |
1403 | match bound.span().find_ancestor_inside(parent_span) { | |
1404 | Some(bound_span) => span_accum.to(bound_span), | |
1405 | None => span_accum, | |
1406 | } | |
1407 | }); | |
1408 | let span = self.lower_span(span); | |
1409 | ||
04454e1e FG |
1410 | match kind { |
1411 | GenericParamKind::Const { .. } => None, | |
1412 | GenericParamKind::Type { .. } => { | |
923072b8 | 1413 | let def_id = self.local_def_id(id).to_def_id(); |
f2b60f7d FG |
1414 | let hir_id = self.next_id(); |
1415 | let res = Res::Def(DefKind::TyParam, def_id); | |
04454e1e FG |
1416 | let ty_path = self.arena.alloc(hir::Path { |
1417 | span: param_span, | |
f2b60f7d FG |
1418 | res, |
1419 | segments: self | |
1420 | .arena | |
1421 | .alloc_from_iter([hir::PathSegment::new(ident, hir_id, res)]), | |
04454e1e FG |
1422 | }); |
1423 | let ty_id = self.next_id(); | |
1424 | let bounded_ty = | |
1425 | self.ty_path(ty_id, param_span, hir::QPath::Resolved(None, ty_path)); | |
1426 | Some(hir::WherePredicate::BoundPredicate(hir::WhereBoundPredicate { | |
2b03887a | 1427 | hir_id: self.next_id(), |
04454e1e FG |
1428 | bounded_ty: self.arena.alloc(bounded_ty), |
1429 | bounds, | |
1430 | span, | |
1431 | bound_generic_params: &[], | |
1432 | origin, | |
1433 | })) | |
dfeec247 | 1434 | } |
04454e1e | 1435 | GenericParamKind::Lifetime => { |
04454e1e | 1436 | let ident = self.lower_ident(ident); |
923072b8 | 1437 | let lt_id = self.next_node_id(); |
487cf647 | 1438 | let lifetime = self.new_named_lifetime(id, lt_id, ident); |
04454e1e FG |
1439 | Some(hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate { |
1440 | lifetime, | |
1441 | span, | |
1442 | bounds, | |
1443 | in_where_clause: false, | |
1444 | })) | |
1445 | } | |
1446 | } | |
416331ca XL |
1447 | } |
1448 | ||
dfeec247 | 1449 | fn lower_where_predicate(&mut self, pred: &WherePredicate) -> hir::WherePredicate<'hir> { |
487cf647 | 1450 | match pred { |
416331ca | 1451 | WherePredicate::BoundPredicate(WhereBoundPredicate { |
487cf647 FG |
1452 | bound_generic_params, |
1453 | bounded_ty, | |
1454 | bounds, | |
416331ca | 1455 | span, |
04454e1e | 1456 | }) => hir::WherePredicate::BoundPredicate(hir::WhereBoundPredicate { |
2b03887a | 1457 | hir_id: self.next_id(), |
9ffffee4 FG |
1458 | bound_generic_params: self |
1459 | .lower_generic_params(bound_generic_params, hir::GenericParamSource::Binder), | |
04454e1e | 1460 | bounded_ty: self |
9ffffee4 | 1461 | .lower_ty(bounded_ty, &ImplTraitContext::Disallowed(ImplTraitPosition::Bound)), |
04454e1e FG |
1462 | bounds: self.arena.alloc_from_iter(bounds.iter().map(|bound| { |
1463 | self.lower_param_bound( | |
1464 | bound, | |
f2b60f7d | 1465 | &ImplTraitContext::Disallowed(ImplTraitPosition::Bound), |
04454e1e FG |
1466 | ) |
1467 | })), | |
487cf647 | 1468 | span: self.lower_span(*span), |
04454e1e | 1469 | origin: PredicateOrigin::WhereClause, |
c295e0f8 | 1470 | }), |
487cf647 FG |
1471 | WherePredicate::RegionPredicate(WhereRegionPredicate { lifetime, bounds, span }) => { |
1472 | hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate { | |
1473 | span: self.lower_span(*span), | |
1474 | lifetime: self.lower_lifetime(lifetime), | |
1475 | bounds: self.lower_param_bounds( | |
1476 | bounds, | |
1477 | &ImplTraitContext::Disallowed(ImplTraitPosition::Bound), | |
1478 | ), | |
1479 | in_where_clause: true, | |
1480 | }) | |
1481 | } | |
1482 | WherePredicate::EqPredicate(WhereEqPredicate { lhs_ty, rhs_ty, span }) => { | |
416331ca | 1483 | hir::WherePredicate::EqPredicate(hir::WhereEqPredicate { |
5099ac24 | 1484 | lhs_ty: self |
9ffffee4 | 1485 | .lower_ty(lhs_ty, &ImplTraitContext::Disallowed(ImplTraitPosition::Bound)), |
5099ac24 | 1486 | rhs_ty: self |
9ffffee4 | 1487 | .lower_ty(rhs_ty, &ImplTraitContext::Disallowed(ImplTraitPosition::Bound)), |
487cf647 | 1488 | span: self.lower_span(*span), |
416331ca | 1489 | }) |
dfeec247 XL |
1490 | } |
1491 | } | |
1492 | } | |
1493 | } |