]> git.lizzy.rs Git - rust.git/blobdiff - crates/hir_ty/src/lower.rs
Merge #11662
[rust.git] / crates / hir_ty / src / lower.rs
index a140dd4057c625fe6d27e25b1f7184cb1c908393..15f91ce799bbcac2373e885598b61dc6109b7891 100644 (file)
@@ -10,6 +10,7 @@
 
 use base_db::CrateId;
 use chalk_ir::{cast::Cast, fold::Shift, interner::HasInterner, Mutability, Safety};
+use hir_def::generics::TypeOrConstParamData;
 use hir_def::intern::Interned;
 use hir_def::{
     adt::StructKind,
     path::{GenericArg, Path, PathSegment, PathSegments},
     resolver::{HasResolver, Resolver, TypeNs},
     type_ref::{TraitBoundModifier, TraitRef as HirTraitRef, TypeBound, TypeRef},
-    AdtId, AssocItemId, ConstId, ConstParamId, EnumId, EnumVariantId, FunctionId, GenericDefId,
-    HasModule, ImplId, ItemContainerId, LocalFieldId, Lookup, StaticId, StructId, TraitId,
-    TypeAliasId, TypeParamId, UnionId, VariantId,
+    AdtId, AssocItemId, ConstId, EnumId, EnumVariantId, FunctionId, GenericDefId, HasModule,
+    ImplId, ItemContainerId, LocalFieldId, Lookup, StaticId, StructId, TraitId, TypeAliasId,
+    UnionId, VariantId,
 };
+use hir_def::{ConstParamId, TypeOrConstParamId};
 use hir_expand::{name::Name, ExpandResult};
 use la_arena::ArenaMap;
 use rustc_hash::FxHashSet;
 use smallvec::SmallVec;
-use stdx::impl_from;
+use stdx::{impl_from, never};
 use syntax::{ast, SmolStr};
 
 use crate::all_super_traits;
@@ -267,7 +269,7 @@ pub fn lower_ty_ext(&self, type_ref: &TypeRef) -> (Ty, Option<TypeNs>) {
                         if let Some(def) = self.resolver.generic_def() {
                             let generics = generics(self.db.upcast(), def);
                             let param = generics
-                                .iter()
+                                .type_iter()
                                 .filter(|(_, data)| {
                                     data.provenance == TypeParamProvenance::ArgumentImplTrait
                                 })
@@ -284,16 +286,21 @@ pub fn lower_ty_ext(&self, type_ref: &TypeRef) -> (Ty, Option<TypeNs>) {
                         let idx = self.impl_trait_counter.get();
                         // FIXME we're probably doing something wrong here
                         self.impl_trait_counter.set(idx + count_impl_traits(type_ref) as u16);
-                        let (parent_params, self_params, list_params, _impl_trait_params) =
-                            if let Some(def) = self.resolver.generic_def() {
-                                let generics = generics(self.db.upcast(), def);
-                                generics.provenance_split()
-                            } else {
-                                (0, 0, 0, 0)
-                            };
+                        let (
+                            parent_params,
+                            self_params,
+                            list_params,
+                            const_params,
+                            _impl_trait_params,
+                        ) = if let Some(def) = self.resolver.generic_def() {
+                            let generics = generics(self.db.upcast(), def);
+                            generics.provenance_split()
+                        } else {
+                            (0, 0, 0, 0, 0)
+                        };
                         TyKind::BoundVar(BoundVar::new(
                             self.in_binders,
-                            idx as usize + parent_params + self_params + list_params,
+                            idx as usize + parent_params + self_params + list_params + const_params,
                         ))
                         .intern(Interner)
                     }
@@ -353,7 +360,7 @@ pub fn lower_ty_ext(&self, type_ref: &TypeRef) -> (Ty, Option<TypeNs>) {
     /// This is only for `generic_predicates_for_param`, where we can't just
     /// lower the self types of the predicates since that could lead to cycles.
     /// So we just check here if the `type_ref` resolves to a generic param, and which.
-    fn lower_ty_only_param(&self, type_ref: &TypeRef) -> Option<TypeParamId> {
+    fn lower_ty_only_param(&self, type_ref: &TypeRef) -> Option<TypeOrConstParamId> {
         let path = match type_ref {
             TypeRef::Path(path) => path,
             _ => return None,
@@ -370,7 +377,7 @@ fn lower_ty_only_param(&self, type_ref: &TypeRef) -> Option<TypeParamId> {
                 _ => return None,
             };
         match resolution {
-            TypeNs::GenericParam(param_id) => Some(param_id),
+            TypeNs::GenericParam(param_id) => Some(param_id.into()),
             _ => None,
         }
     }
@@ -469,10 +476,10 @@ pub(crate) fn lower_partly_resolved_path(
                 );
                 match self.type_param_mode {
                     TypeParamLoweringMode::Placeholder => {
-                        TyKind::Placeholder(to_placeholder_idx(self.db, param_id))
+                        TyKind::Placeholder(to_placeholder_idx(self.db, param_id.into()))
                     }
                     TypeParamLoweringMode::Variable => {
-                        let idx = generics.param_idx(param_id).expect("matching generics");
+                        let idx = generics.param_idx(param_id.into()).expect("matching generics");
                         TyKind::BoundVar(BoundVar::new(self.in_binders, idx))
                     }
                 }
@@ -637,9 +644,10 @@ fn substs_from_path_segment(
         let mut substs = Vec::new();
         let def_generics = def_generic.map(|def| generics(self.db.upcast(), def));
 
-        let (parent_params, self_params, type_params, impl_trait_params) =
-            def_generics.map_or((0, 0, 0, 0), |g| g.provenance_split());
-        let total_len = parent_params + self_params + type_params + impl_trait_params;
+        let (parent_params, self_params, type_params, const_params, impl_trait_params) =
+            def_generics.map_or((0, 0, 0, 0, 0), |g| g.provenance_split());
+        let total_len =
+            parent_params + self_params + type_params + const_params + impl_trait_params;
 
         substs.extend(iter::repeat(TyKind::Error.intern(Interner)).take(parent_params));
 
@@ -758,11 +766,13 @@ pub(crate) fn lower_where_predicate(
             | WherePredicate::TypeBound { target, bound } => {
                 let self_ty = match target {
                     WherePredicateTypeTarget::TypeRef(type_ref) => self.lower_ty(type_ref),
-                    WherePredicateTypeTarget::TypeParam(param_id) => {
+                    WherePredicateTypeTarget::TypeOrConstParam(param_id) => {
                         let generic_def = self.resolver.generic_def().expect("generics in scope");
                         let generics = generics(self.db.upcast(), generic_def);
-                        let param_id =
-                            hir_def::TypeParamId { parent: generic_def, local_id: *param_id };
+                        let param_id = hir_def::TypeOrConstParamId {
+                            parent: generic_def,
+                            local_id: *param_id,
+                        };
                         let placeholder = to_placeholder_idx(self.db, param_id);
                         match self.type_param_mode {
                             TypeParamLoweringMode::Placeholder => TyKind::Placeholder(placeholder),
@@ -973,7 +983,7 @@ fn named_associated_type_shorthand_candidates<R>(
             db.impl_trait(impl_id)?.into_value_and_skipped_binders().0,
         ),
         TypeNs::GenericParam(param_id) => {
-            let predicates = db.generic_predicates_for_param(def, param_id, assoc_name);
+            let predicates = db.generic_predicates_for_param(def, param_id.into(), assoc_name);
             let res = predicates.iter().find_map(|pred| match pred.skip_binders().skip_binders() {
                 // FIXME: how to correctly handle higher-ranked bounds here?
                 WhereClause::Implemented(tr) => search(
@@ -987,11 +997,9 @@ fn named_associated_type_shorthand_candidates<R>(
                 return res;
             }
             // Handle `Self::Type` referring to own associated type in trait definitions
-            if let GenericDefId::TraitId(trait_id) = param_id.parent {
+            if let GenericDefId::TraitId(trait_id) = param_id.parent() {
                 let generics = generics(db.upcast(), trait_id.into());
-                if generics.params.types[param_id.local_id].provenance
-                    == TypeParamProvenance::TraitSelf
-                {
+                if generics.params.tocs[param_id.local_id()].is_trait_self() {
                     let trait_ref = TyBuilder::trait_ref(db, trait_id)
                         .fill_with_bound_vars(DebruijnIndex::INNERMOST, 0)
                         .build();
@@ -1036,7 +1044,7 @@ pub(crate) fn field_types_query(
 pub(crate) fn generic_predicates_for_param_query(
     db: &dyn HirDatabase,
     def: GenericDefId,
-    param_id: TypeParamId,
+    param_id: TypeOrConstParamId,
     assoc_name: Option<Name>,
 ) -> Arc<[Binders<QuantifiedWhereClause>]> {
     let resolver = def.resolver(db.upcast());
@@ -1051,11 +1059,11 @@ pub(crate) fn generic_predicates_for_param_query(
             | WherePredicate::TypeBound { target, bound, .. } => {
                 match target {
                     WherePredicateTypeTarget::TypeRef(type_ref) => {
-                        if ctx.lower_ty_only_param(type_ref) != Some(param_id) {
+                        if ctx.lower_ty_only_param(type_ref) != Some(param_id.into()) {
                             return false;
                         }
                     }
-                    WherePredicateTypeTarget::TypeParam(local_id) => {
+                    WherePredicateTypeTarget::TypeOrConstParam(local_id) => {
                         if *local_id != param_id.local_id {
                             return false;
                         }
@@ -1105,7 +1113,7 @@ pub(crate) fn generic_predicates_for_param_recover(
     _db: &dyn HirDatabase,
     _cycle: &[String],
     _def: &GenericDefId,
-    _param_id: &TypeParamId,
+    _param_id: &TypeOrConstParamId,
     _assoc_name: &Option<Name>,
 ) -> Arc<[Binders<QuantifiedWhereClause>]> {
     Arc::new([])
@@ -1233,9 +1241,17 @@ pub(crate) fn generic_defaults_query(
     let generic_params = generics(db.upcast(), def);
 
     let defaults = generic_params
-        .iter()
+        .toc_iter()
         .enumerate()
         .map(|(idx, (_, p))| {
+            let p = match p {
+                TypeOrConstParamData::TypeParamData(p) => p,
+                TypeOrConstParamData::ConstParamData(_) => {
+                    // FIXME: here we should add const generic parameters
+                    let ty = TyKind::Error.intern(Interner);
+                    return crate::make_only_type_binders(idx, ty);
+                }
+            };
             let mut ty =
                 p.default.as_ref().map_or(TyKind::Error.intern(Interner), |t| ctx.lower_ty(t));
 
@@ -1267,7 +1283,7 @@ pub(crate) fn generic_defaults_recover(
 
     // we still need one default per parameter
     let defaults = generic_params
-        .iter()
+        .toc_iter()
         .enumerate()
         .map(|(idx, _)| {
             let ty = TyKind::Error.intern(Interner);
@@ -1497,13 +1513,19 @@ pub(crate) fn impl_self_ty_query(db: &dyn HirDatabase, impl_id: ImplId) -> Binde
     make_binders(&generics, ctx.lower_ty(&impl_data.self_ty))
 }
 
+// returns None if def is a type arg
 pub(crate) fn const_param_ty_query(db: &dyn HirDatabase, def: ConstParamId) -> Ty {
-    let parent_data = db.generic_params(def.parent);
-    let data = &parent_data.consts[def.local_id];
-    let resolver = def.parent.resolver(db.upcast());
+    let parent_data = db.generic_params(def.parent());
+    let data = &parent_data.tocs[def.local_id()];
+    let resolver = def.parent().resolver(db.upcast());
     let ctx = TyLoweringContext::new(db, &resolver);
-
-    ctx.lower_ty(&data.ty)
+    match data {
+        TypeOrConstParamData::TypeParamData(_) => {
+            never!();
+            Ty::new(Interner, TyKind::Error)
+        }
+        TypeOrConstParamData::ConstParamData(d) => ctx.lower_ty(&d.ty),
+    }
 }
 
 pub(crate) fn impl_self_ty_recover(