From 1d0e27254d6376e980dc19e67dfcc598c7e97231 Mon Sep 17 00:00:00 2001 From: Florian Diebold Date: Fri, 22 May 2020 17:14:53 +0200 Subject: Split up chalk module a bit --- crates/ra_hir_ty/src/traits/chalk/mapping.rs | 672 +++++++++++++++++++++++++++ 1 file changed, 672 insertions(+) create mode 100644 crates/ra_hir_ty/src/traits/chalk/mapping.rs (limited to 'crates/ra_hir_ty/src/traits/chalk/mapping.rs') diff --git a/crates/ra_hir_ty/src/traits/chalk/mapping.rs b/crates/ra_hir_ty/src/traits/chalk/mapping.rs new file mode 100644 index 000000000..a83d82fd8 --- /dev/null +++ b/crates/ra_hir_ty/src/traits/chalk/mapping.rs @@ -0,0 +1,672 @@ +//! This module contains the implementations of the `ToChalk` trait, which +//! handles conversion between our data types and their corresponding types in +//! Chalk (in both directions); plus some helper functions for more specialized +//! conversions. + +use chalk_ir::{ + cast::Cast, fold::shift::Shift, interner::HasInterner, PlaceholderIndex, Scalar, TypeName, + UniverseIndex, +}; + +use hir_def::{type_ref::Mutability, AssocContainerId, GenericDefId, Lookup, TypeAliasId}; +use ra_db::salsa::InternKey; + +use crate::{ + db::HirDatabase, + primitive::{FloatBitness, FloatTy, IntBitness, IntTy, Signedness, Uncertain}, + traits::{builtin, AssocTyValue, Canonical, Impl, Obligation}, + ApplicationTy, GenericPredicate, InEnvironment, ProjectionPredicate, ProjectionTy, Substs, + TraitEnvironment, TraitRef, Ty, TypeCtor, +}; + +use super::interner::*; +use super::*; + +impl ToChalk for Ty { + type Chalk = chalk_ir::Ty; + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Ty { + match self { + Ty::Apply(apply_ty) => { + if let TypeCtor::Ref(m) = apply_ty.ctor { + return ref_to_chalk(db, m, apply_ty.parameters); + } + let name = apply_ty.ctor.to_chalk(db); + let substitution = apply_ty.parameters.to_chalk(db); + chalk_ir::ApplicationTy { name, substitution }.cast(&Interner).intern(&Interner) + } + Ty::Projection(proj_ty) => { + let associated_ty_id = proj_ty.associated_ty.to_chalk(db); + let substitution = proj_ty.parameters.to_chalk(db); + chalk_ir::AliasTy::Projection(chalk_ir::ProjectionTy { + associated_ty_id, + substitution, + }) + .cast(&Interner) + .intern(&Interner) + } + Ty::Placeholder(id) => { + let interned_id = db.intern_type_param_id(id); + PlaceholderIndex { + ui: UniverseIndex::ROOT, + idx: interned_id.as_intern_id().as_usize(), + } + .to_ty::(&Interner) + } + Ty::Bound(idx) => chalk_ir::TyData::BoundVar(idx).intern(&Interner), + Ty::Infer(_infer_ty) => panic!("uncanonicalized infer ty"), + Ty::Dyn(predicates) => { + let where_clauses = chalk_ir::QuantifiedWhereClauses::from( + &Interner, + predicates.iter().filter(|p| !p.is_error()).cloned().map(|p| p.to_chalk(db)), + ); + let bounded_ty = chalk_ir::DynTy { bounds: make_binders(where_clauses, 1) }; + chalk_ir::TyData::Dyn(bounded_ty).intern(&Interner) + } + Ty::Opaque(_) | Ty::Unknown => { + let substitution = chalk_ir::Substitution::empty(&Interner); + let name = TypeName::Error; + chalk_ir::ApplicationTy { name, substitution }.cast(&Interner).intern(&Interner) + } + } + } + fn from_chalk(db: &dyn HirDatabase, chalk: chalk_ir::Ty) -> Self { + match chalk.data(&Interner).clone() { + chalk_ir::TyData::Apply(apply_ty) => match apply_ty.name { + TypeName::Error => Ty::Unknown, + TypeName::Ref(m) => ref_from_chalk(db, m, apply_ty.substitution), + _ => { + let ctor = from_chalk(db, apply_ty.name); + let parameters = from_chalk(db, apply_ty.substitution); + Ty::Apply(ApplicationTy { ctor, parameters }) + } + }, + chalk_ir::TyData::Placeholder(idx) => { + assert_eq!(idx.ui, UniverseIndex::ROOT); + let interned_id = crate::db::GlobalTypeParamId::from_intern_id( + crate::salsa::InternId::from(idx.idx), + ); + Ty::Placeholder(db.lookup_intern_type_param_id(interned_id)) + } + chalk_ir::TyData::Alias(chalk_ir::AliasTy::Projection(proj)) => { + let associated_ty = from_chalk(db, proj.associated_ty_id); + let parameters = from_chalk(db, proj.substitution); + Ty::Projection(ProjectionTy { associated_ty, parameters }) + } + chalk_ir::TyData::Alias(chalk_ir::AliasTy::Opaque(_)) => unimplemented!(), + chalk_ir::TyData::Function(_) => unimplemented!(), + chalk_ir::TyData::BoundVar(idx) => Ty::Bound(idx), + chalk_ir::TyData::InferenceVar(_iv) => Ty::Unknown, + chalk_ir::TyData::Dyn(where_clauses) => { + assert_eq!(where_clauses.bounds.binders.len(&Interner), 1); + let predicates = where_clauses + .bounds + .skip_binders() + .iter(&Interner) + .map(|c| from_chalk(db, c.clone())) + .collect(); + Ty::Dyn(predicates) + } + } + } +} + +const LIFETIME_PLACEHOLDER: PlaceholderIndex = + PlaceholderIndex { ui: UniverseIndex::ROOT, idx: usize::MAX }; + +/// We currently don't model lifetimes, but Chalk does. So, we have to insert a +/// fake lifetime here, because Chalks built-in logic may expect it to be there. +fn ref_to_chalk( + db: &dyn HirDatabase, + mutability: Mutability, + subst: Substs, +) -> chalk_ir::Ty { + let arg = subst[0].clone().to_chalk(db); + let lifetime = LIFETIME_PLACEHOLDER.to_lifetime(&Interner); + chalk_ir::ApplicationTy { + name: TypeName::Ref(mutability.to_chalk(db)), + substitution: chalk_ir::Substitution::from( + &Interner, + vec![lifetime.cast(&Interner), arg.cast(&Interner)], + ), + } + .intern(&Interner) +} + +/// Here we remove the lifetime from the type we got from Chalk. +fn ref_from_chalk( + db: &dyn HirDatabase, + mutability: chalk_ir::Mutability, + subst: chalk_ir::Substitution, +) -> Ty { + let tys = subst + .iter(&Interner) + .filter_map(|p| Some(from_chalk(db, p.ty(&Interner)?.clone()))) + .collect(); + Ty::apply(TypeCtor::Ref(from_chalk(db, mutability)), Substs(tys)) +} + +impl ToChalk for Substs { + type Chalk = chalk_ir::Substitution; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Substitution { + chalk_ir::Substitution::from(&Interner, self.iter().map(|ty| ty.clone().to_chalk(db))) + } + + fn from_chalk(db: &dyn HirDatabase, parameters: chalk_ir::Substitution) -> Substs { + let tys = parameters + .iter(&Interner) + .map(|p| match p.ty(&Interner) { + Some(ty) => from_chalk(db, ty.clone()), + None => unimplemented!(), + }) + .collect(); + Substs(tys) + } +} + +impl ToChalk for TraitRef { + type Chalk = chalk_ir::TraitRef; + + fn to_chalk(self: TraitRef, db: &dyn HirDatabase) -> chalk_ir::TraitRef { + let trait_id = self.trait_.to_chalk(db); + let substitution = self.substs.to_chalk(db); + chalk_ir::TraitRef { trait_id, substitution } + } + + fn from_chalk(db: &dyn HirDatabase, trait_ref: chalk_ir::TraitRef) -> Self { + let trait_ = from_chalk(db, trait_ref.trait_id); + let substs = from_chalk(db, trait_ref.substitution); + TraitRef { trait_, substs } + } +} + +impl ToChalk for hir_def::TraitId { + type Chalk = TraitId; + + fn to_chalk(self, _db: &dyn HirDatabase) -> TraitId { + chalk_ir::TraitId(self.as_intern_id()) + } + + fn from_chalk(_db: &dyn HirDatabase, trait_id: TraitId) -> hir_def::TraitId { + InternKey::from_intern_id(trait_id.0) + } +} + +impl ToChalk for TypeCtor { + type Chalk = TypeName; + + fn to_chalk(self, db: &dyn HirDatabase) -> TypeName { + match self { + TypeCtor::AssociatedType(type_alias) => { + let type_id = type_alias.to_chalk(db); + TypeName::AssociatedType(type_id) + } + + TypeCtor::Bool => TypeName::Scalar(Scalar::Bool), + TypeCtor::Char => TypeName::Scalar(Scalar::Char), + TypeCtor::Int(Uncertain::Known(int_ty)) => TypeName::Scalar(int_ty_to_chalk(int_ty)), + TypeCtor::Float(Uncertain::Known(FloatTy { bitness: FloatBitness::X32 })) => { + TypeName::Scalar(Scalar::Float(chalk_ir::FloatTy::F32)) + } + TypeCtor::Float(Uncertain::Known(FloatTy { bitness: FloatBitness::X64 })) => { + TypeName::Scalar(Scalar::Float(chalk_ir::FloatTy::F64)) + } + + TypeCtor::Tuple { cardinality } => TypeName::Tuple(cardinality.into()), + TypeCtor::RawPtr(mutability) => TypeName::Raw(mutability.to_chalk(db)), + TypeCtor::Slice => TypeName::Slice, + TypeCtor::Ref(mutability) => TypeName::Ref(mutability.to_chalk(db)), + TypeCtor::Str => TypeName::Str, + TypeCtor::Int(Uncertain::Unknown) + | TypeCtor::Float(Uncertain::Unknown) + | TypeCtor::Adt(_) + | TypeCtor::Array + | TypeCtor::FnDef(_) + | TypeCtor::FnPtr { .. } + | TypeCtor::Never + | TypeCtor::Closure { .. } => { + // other TypeCtors get interned and turned into a chalk StructId + let struct_id = db.intern_type_ctor(self).into(); + TypeName::Adt(struct_id) + } + } + } + + fn from_chalk(db: &dyn HirDatabase, type_name: TypeName) -> TypeCtor { + match type_name { + TypeName::Adt(struct_id) => db.lookup_intern_type_ctor(struct_id.into()), + TypeName::AssociatedType(type_id) => TypeCtor::AssociatedType(from_chalk(db, type_id)), + TypeName::OpaqueType(_) => unreachable!(), + + TypeName::Scalar(Scalar::Bool) => TypeCtor::Bool, + TypeName::Scalar(Scalar::Char) => TypeCtor::Char, + TypeName::Scalar(Scalar::Int(int_ty)) => TypeCtor::Int(Uncertain::Known(IntTy { + signedness: Signedness::Signed, + bitness: bitness_from_chalk_int(int_ty), + })), + TypeName::Scalar(Scalar::Uint(uint_ty)) => TypeCtor::Int(Uncertain::Known(IntTy { + signedness: Signedness::Unsigned, + bitness: bitness_from_chalk_uint(uint_ty), + })), + TypeName::Scalar(Scalar::Float(chalk_ir::FloatTy::F32)) => { + TypeCtor::Float(Uncertain::Known(FloatTy { bitness: FloatBitness::X32 })) + } + TypeName::Scalar(Scalar::Float(chalk_ir::FloatTy::F64)) => { + TypeCtor::Float(Uncertain::Known(FloatTy { bitness: FloatBitness::X64 })) + } + TypeName::Tuple(cardinality) => TypeCtor::Tuple { cardinality: cardinality as u16 }, + TypeName::Raw(mutability) => TypeCtor::RawPtr(from_chalk(db, mutability)), + TypeName::Slice => TypeCtor::Slice, + TypeName::Ref(mutability) => TypeCtor::Ref(from_chalk(db, mutability)), + TypeName::Str => TypeCtor::Str, + + TypeName::FnDef(_) => unreachable!(), + + TypeName::Error => { + // this should not be reached, since we don't represent TypeName::Error with TypeCtor + unreachable!() + } + } + } +} + +fn bitness_from_chalk_uint(uint_ty: chalk_ir::UintTy) -> IntBitness { + use chalk_ir::UintTy; + + match uint_ty { + UintTy::Usize => IntBitness::Xsize, + UintTy::U8 => IntBitness::X8, + UintTy::U16 => IntBitness::X16, + UintTy::U32 => IntBitness::X32, + UintTy::U64 => IntBitness::X64, + UintTy::U128 => IntBitness::X128, + } +} + +fn bitness_from_chalk_int(int_ty: chalk_ir::IntTy) -> IntBitness { + use chalk_ir::IntTy; + + match int_ty { + IntTy::Isize => IntBitness::Xsize, + IntTy::I8 => IntBitness::X8, + IntTy::I16 => IntBitness::X16, + IntTy::I32 => IntBitness::X32, + IntTy::I64 => IntBitness::X64, + IntTy::I128 => IntBitness::X128, + } +} + +fn int_ty_to_chalk(int_ty: IntTy) -> Scalar { + use chalk_ir::{IntTy, UintTy}; + + match int_ty.signedness { + Signedness::Signed => Scalar::Int(match int_ty.bitness { + IntBitness::Xsize => IntTy::Isize, + IntBitness::X8 => IntTy::I8, + IntBitness::X16 => IntTy::I16, + IntBitness::X32 => IntTy::I32, + IntBitness::X64 => IntTy::I64, + IntBitness::X128 => IntTy::I128, + }), + Signedness::Unsigned => Scalar::Uint(match int_ty.bitness { + IntBitness::Xsize => UintTy::Usize, + IntBitness::X8 => UintTy::U8, + IntBitness::X16 => UintTy::U16, + IntBitness::X32 => UintTy::U32, + IntBitness::X64 => UintTy::U64, + IntBitness::X128 => UintTy::U128, + }), + } +} + +impl ToChalk for Mutability { + type Chalk = chalk_ir::Mutability; + fn to_chalk(self, _db: &dyn HirDatabase) -> Self::Chalk { + match self { + Mutability::Shared => chalk_ir::Mutability::Not, + Mutability::Mut => chalk_ir::Mutability::Mut, + } + } + fn from_chalk(_db: &dyn HirDatabase, chalk: Self::Chalk) -> Self { + match chalk { + chalk_ir::Mutability::Mut => Mutability::Mut, + chalk_ir::Mutability::Not => Mutability::Shared, + } + } +} + +impl ToChalk for Impl { + type Chalk = ImplId; + + fn to_chalk(self, db: &dyn HirDatabase) -> ImplId { + db.intern_chalk_impl(self).into() + } + + fn from_chalk(db: &dyn HirDatabase, impl_id: ImplId) -> Impl { + db.lookup_intern_chalk_impl(impl_id.into()) + } +} + +impl ToChalk for TypeAliasId { + type Chalk = AssocTypeId; + + fn to_chalk(self, _db: &dyn HirDatabase) -> AssocTypeId { + chalk_ir::AssocTypeId(self.as_intern_id()) + } + + fn from_chalk(_db: &dyn HirDatabase, type_alias_id: AssocTypeId) -> TypeAliasId { + InternKey::from_intern_id(type_alias_id.0) + } +} + +impl ToChalk for AssocTyValue { + type Chalk = AssociatedTyValueId; + + fn to_chalk(self, db: &dyn HirDatabase) -> AssociatedTyValueId { + db.intern_assoc_ty_value(self).into() + } + + fn from_chalk(db: &dyn HirDatabase, assoc_ty_value_id: AssociatedTyValueId) -> AssocTyValue { + db.lookup_intern_assoc_ty_value(assoc_ty_value_id.into()) + } +} + +impl ToChalk for GenericPredicate { + type Chalk = chalk_ir::QuantifiedWhereClause; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::QuantifiedWhereClause { + match self { + GenericPredicate::Implemented(trait_ref) => { + let chalk_trait_ref = trait_ref.to_chalk(db); + let chalk_trait_ref = chalk_trait_ref.shifted_in(&Interner); + make_binders(chalk_ir::WhereClause::Implemented(chalk_trait_ref), 0) + } + GenericPredicate::Projection(projection_pred) => { + let ty = projection_pred.ty.to_chalk(db).shifted_in(&Interner); + let projection = projection_pred.projection_ty.to_chalk(db).shifted_in(&Interner); + let alias = chalk_ir::AliasTy::Projection(projection); + make_binders(chalk_ir::WhereClause::AliasEq(chalk_ir::AliasEq { alias, ty }), 0) + } + GenericPredicate::Error => panic!("tried passing GenericPredicate::Error to Chalk"), + } + } + + fn from_chalk( + db: &dyn HirDatabase, + where_clause: chalk_ir::QuantifiedWhereClause, + ) -> GenericPredicate { + // we don't produce any where clauses with binders and can't currently deal with them + match where_clause + .skip_binders() + .shifted_out(&Interner) + .expect("unexpected bound vars in where clause") + { + chalk_ir::WhereClause::Implemented(tr) => { + GenericPredicate::Implemented(from_chalk(db, tr)) + } + chalk_ir::WhereClause::AliasEq(projection_eq) => { + let projection_ty = from_chalk( + db, + match projection_eq.alias { + chalk_ir::AliasTy::Projection(p) => p, + _ => unimplemented!(), + }, + ); + let ty = from_chalk(db, projection_eq.ty); + GenericPredicate::Projection(ProjectionPredicate { projection_ty, ty }) + } + } + } +} + +impl ToChalk for ProjectionTy { + type Chalk = chalk_ir::ProjectionTy; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::ProjectionTy { + chalk_ir::ProjectionTy { + associated_ty_id: self.associated_ty.to_chalk(db), + substitution: self.parameters.to_chalk(db), + } + } + + fn from_chalk( + db: &dyn HirDatabase, + projection_ty: chalk_ir::ProjectionTy, + ) -> ProjectionTy { + ProjectionTy { + associated_ty: from_chalk(db, projection_ty.associated_ty_id), + parameters: from_chalk(db, projection_ty.substitution), + } + } +} + +impl ToChalk for ProjectionPredicate { + type Chalk = chalk_ir::AliasEq; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::AliasEq { + chalk_ir::AliasEq { + alias: chalk_ir::AliasTy::Projection(self.projection_ty.to_chalk(db)), + ty: self.ty.to_chalk(db), + } + } + + fn from_chalk(_db: &dyn HirDatabase, _normalize: chalk_ir::AliasEq) -> Self { + unimplemented!() + } +} + +impl ToChalk for Obligation { + type Chalk = chalk_ir::DomainGoal; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::DomainGoal { + match self { + Obligation::Trait(tr) => tr.to_chalk(db).cast(&Interner), + Obligation::Projection(pr) => pr.to_chalk(db).cast(&Interner), + } + } + + fn from_chalk(_db: &dyn HirDatabase, _goal: chalk_ir::DomainGoal) -> Self { + unimplemented!() + } +} + +impl ToChalk for Canonical +where + T: ToChalk, + T::Chalk: HasInterner, +{ + type Chalk = chalk_ir::Canonical; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Canonical { + let parameter = chalk_ir::CanonicalVarKind::new( + chalk_ir::VariableKind::Ty, + chalk_ir::UniverseIndex::ROOT, + ); + let value = self.value.to_chalk(db); + chalk_ir::Canonical { + value, + binders: chalk_ir::CanonicalVarKinds::from(&Interner, vec![parameter; self.num_vars]), + } + } + + fn from_chalk(db: &dyn HirDatabase, canonical: chalk_ir::Canonical) -> Canonical { + Canonical { + num_vars: canonical.binders.len(&Interner), + value: from_chalk(db, canonical.value), + } + } +} + +impl ToChalk for Arc { + type Chalk = chalk_ir::Environment; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Environment { + let mut clauses = Vec::new(); + for pred in &self.predicates { + if pred.is_error() { + // for env, we just ignore errors + continue; + } + let program_clause: chalk_ir::ProgramClause = + pred.clone().to_chalk(db).cast(&Interner); + clauses.push(program_clause.into_from_env_clause(&Interner)); + } + chalk_ir::Environment::new(&Interner).add_clauses(&Interner, clauses) + } + + fn from_chalk( + _db: &dyn HirDatabase, + _env: chalk_ir::Environment, + ) -> Arc { + unimplemented!() + } +} + +impl ToChalk for InEnvironment +where + T::Chalk: chalk_ir::interner::HasInterner, +{ + type Chalk = chalk_ir::InEnvironment; + + fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::InEnvironment { + chalk_ir::InEnvironment { + environment: self.environment.to_chalk(db), + goal: self.value.to_chalk(db), + } + } + + fn from_chalk( + db: &dyn HirDatabase, + in_env: chalk_ir::InEnvironment, + ) -> InEnvironment { + InEnvironment { + environment: from_chalk(db, in_env.environment), + value: from_chalk(db, in_env.goal), + } + } +} + +impl ToChalk for builtin::BuiltinImplData { + type Chalk = ImplDatum; + + fn to_chalk(self, db: &dyn HirDatabase) -> ImplDatum { + let impl_type = chalk_rust_ir::ImplType::External; + let where_clauses = self.where_clauses.into_iter().map(|w| w.to_chalk(db)).collect(); + + let impl_datum_bound = + chalk_rust_ir::ImplDatumBound { trait_ref: self.trait_ref.to_chalk(db), where_clauses }; + let associated_ty_value_ids = + self.assoc_ty_values.into_iter().map(|v| v.to_chalk(db)).collect(); + chalk_rust_ir::ImplDatum { + binders: make_binders(impl_datum_bound, self.num_vars), + impl_type, + polarity: chalk_rust_ir::Polarity::Positive, + associated_ty_value_ids, + } + } + + fn from_chalk(_db: &dyn HirDatabase, _data: ImplDatum) -> Self { + unimplemented!() + } +} + +impl ToChalk for builtin::BuiltinImplAssocTyValueData { + type Chalk = AssociatedTyValue; + + fn to_chalk(self, db: &dyn HirDatabase) -> AssociatedTyValue { + let ty = self.value.to_chalk(db); + let value_bound = chalk_rust_ir::AssociatedTyValueBound { ty }; + + chalk_rust_ir::AssociatedTyValue { + associated_ty_id: self.assoc_ty_id.to_chalk(db), + impl_id: self.impl_.to_chalk(db), + value: make_binders(value_bound, self.num_vars), + } + } + + fn from_chalk( + _db: &dyn HirDatabase, + _data: AssociatedTyValue, + ) -> builtin::BuiltinImplAssocTyValueData { + unimplemented!() + } +} + +pub(super) fn make_binders(value: T, num_vars: usize) -> chalk_ir::Binders +where + T: HasInterner, +{ + chalk_ir::Binders::new( + chalk_ir::VariableKinds::from( + &Interner, + std::iter::repeat(chalk_ir::VariableKind::Ty).take(num_vars), + ), + value, + ) +} + +pub(super) fn convert_where_clauses( + db: &dyn HirDatabase, + def: GenericDefId, + substs: &Substs, +) -> Vec> { + let generic_predicates = db.generic_predicates(def); + let mut result = Vec::with_capacity(generic_predicates.len()); + for pred in generic_predicates.iter() { + if pred.value.is_error() { + // skip errored predicates completely + continue; + } + result.push(pred.clone().subst(substs).to_chalk(db)); + } + result +} + +pub(super) fn generic_predicate_to_inline_bound( + db: &dyn HirDatabase, + pred: &GenericPredicate, + self_ty: &Ty, +) -> Option> { + // An InlineBound is like a GenericPredicate, except the self type is left out. + // We don't have a special type for this, but Chalk does. + match pred { + GenericPredicate::Implemented(trait_ref) => { + if &trait_ref.substs[0] != self_ty { + // we can only convert predicates back to type bounds if they + // have the expected self type + return None; + } + let args_no_self = trait_ref.substs[1..] + .iter() + .map(|ty| ty.clone().to_chalk(db).cast(&Interner)) + .collect(); + let trait_bound = + chalk_rust_ir::TraitBound { trait_id: trait_ref.trait_.to_chalk(db), args_no_self }; + Some(chalk_rust_ir::InlineBound::TraitBound(trait_bound)) + } + GenericPredicate::Projection(proj) => { + if &proj.projection_ty.parameters[0] != self_ty { + return None; + } + let trait_ = match proj.projection_ty.associated_ty.lookup(db.upcast()).container { + AssocContainerId::TraitId(t) => t, + _ => panic!("associated type not in trait"), + }; + let args_no_self = proj.projection_ty.parameters[1..] + .iter() + .map(|ty| ty.clone().to_chalk(db).cast(&Interner)) + .collect(); + let alias_eq_bound = chalk_rust_ir::AliasEqBound { + value: proj.ty.clone().to_chalk(db), + trait_bound: chalk_rust_ir::TraitBound { + trait_id: trait_.to_chalk(db), + args_no_self, + }, + associated_ty_id: proj.projection_ty.associated_ty.to_chalk(db), + parameters: Vec::new(), // FIXME we don't support generic associated types yet + }; + Some(chalk_rust_ir::InlineBound::AliasEqBound(alias_eq_bound)) + } + GenericPredicate::Error => None, + } +} -- cgit v1.2.3