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