rust/crates/hir_ty/src/chalk_db.rs
Laurențiu Nicola c930dcca13 Bump chalk
2021-09-09 21:12:38 +03:00

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//! The implementation of `RustIrDatabase` for Chalk, which provides information
//! about the code that Chalk needs.
use std::sync::Arc;
use cov_mark::hit;
use tracing::debug;
use chalk_ir::{cast::Cast, fold::shift::Shift, CanonicalVarKinds};
use chalk_solve::rust_ir::{self, OpaqueTyDatumBound, WellKnownTrait};
use base_db::CrateId;
use hir_def::{
lang_item::{lang_attr, LangItemTarget},
AssocContainerId, AssocItemId, GenericDefId, HasModule, Lookup, ModuleId, TypeAliasId,
};
use hir_expand::name::name;
use crate::{
db::HirDatabase,
display::HirDisplay,
from_assoc_type_id, from_chalk_trait_id, from_foreign_def_id, make_only_type_binders,
mapping::{from_chalk, ToChalk, TypeAliasAsValue},
method_resolution::{TraitImpls, TyFingerprint, ALL_FLOAT_FPS, ALL_INT_FPS},
to_assoc_type_id, to_chalk_trait_id,
traits::ChalkContext,
utils::generics,
AliasEq, AliasTy, BoundVar, CallableDefId, DebruijnIndex, FnDefId, Interner, ProjectionTy,
ProjectionTyExt, QuantifiedWhereClause, Substitution, TraitRef, TraitRefExt, Ty, TyBuilder,
TyExt, TyKind, WhereClause,
};
pub(crate) type AssociatedTyDatum = chalk_solve::rust_ir::AssociatedTyDatum<Interner>;
pub(crate) type TraitDatum = chalk_solve::rust_ir::TraitDatum<Interner>;
pub(crate) type StructDatum = chalk_solve::rust_ir::AdtDatum<Interner>;
pub(crate) type ImplDatum = chalk_solve::rust_ir::ImplDatum<Interner>;
pub(crate) type OpaqueTyDatum = chalk_solve::rust_ir::OpaqueTyDatum<Interner>;
pub(crate) type AssocTypeId = chalk_ir::AssocTypeId<Interner>;
pub(crate) type TraitId = chalk_ir::TraitId<Interner>;
pub(crate) type AdtId = chalk_ir::AdtId<Interner>;
pub(crate) type ImplId = chalk_ir::ImplId<Interner>;
pub(crate) type AssociatedTyValueId = chalk_solve::rust_ir::AssociatedTyValueId<Interner>;
pub(crate) type AssociatedTyValue = chalk_solve::rust_ir::AssociatedTyValue<Interner>;
pub(crate) type FnDefDatum = chalk_solve::rust_ir::FnDefDatum<Interner>;
pub(crate) type Variances = chalk_ir::Variances<Interner>;
impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
fn associated_ty_data(&self, id: AssocTypeId) -> Arc<AssociatedTyDatum> {
self.db.associated_ty_data(id)
}
fn trait_datum(&self, trait_id: TraitId) -> Arc<TraitDatum> {
self.db.trait_datum(self.krate, trait_id)
}
fn adt_datum(&self, struct_id: AdtId) -> Arc<StructDatum> {
self.db.struct_datum(self.krate, struct_id)
}
fn adt_repr(&self, _struct_id: AdtId) -> Arc<rust_ir::AdtRepr<Interner>> {
// FIXME: keep track of these
Arc::new(rust_ir::AdtRepr { c: false, packed: false, int: None })
}
fn discriminant_type(&self, _ty: chalk_ir::Ty<Interner>) -> chalk_ir::Ty<Interner> {
// FIXME: keep track of this
chalk_ir::TyKind::Scalar(chalk_ir::Scalar::Uint(chalk_ir::UintTy::U32)).intern(&Interner)
}
fn impl_datum(&self, impl_id: ImplId) -> Arc<ImplDatum> {
self.db.impl_datum(self.krate, impl_id)
}
fn fn_def_datum(
&self,
fn_def_id: chalk_ir::FnDefId<Interner>,
) -> Arc<rust_ir::FnDefDatum<Interner>> {
self.db.fn_def_datum(self.krate, fn_def_id)
}
fn impls_for_trait(
&self,
trait_id: TraitId,
parameters: &[chalk_ir::GenericArg<Interner>],
binders: &CanonicalVarKinds<Interner>,
) -> Vec<ImplId> {
debug!("impls_for_trait {:?}", trait_id);
let trait_: hir_def::TraitId = from_chalk_trait_id(trait_id);
let ty: Ty = parameters[0].assert_ty_ref(&Interner).clone();
fn binder_kind(
ty: &Ty,
binders: &CanonicalVarKinds<Interner>,
) -> Option<chalk_ir::TyVariableKind> {
if let TyKind::BoundVar(bv) = ty.kind(&Interner) {
let binders = binders.as_slice(&Interner);
if bv.debruijn == DebruijnIndex::INNERMOST {
if let chalk_ir::VariableKind::Ty(tk) = binders[bv.index].kind {
return Some(tk);
}
}
}
None
}
let self_ty_fp = TyFingerprint::for_trait_impl(&ty);
let fps: &[TyFingerprint] = match binder_kind(&ty, binders) {
Some(chalk_ir::TyVariableKind::Integer) => &ALL_INT_FPS,
Some(chalk_ir::TyVariableKind::Float) => &ALL_FLOAT_FPS,
_ => self_ty_fp.as_ref().map(std::slice::from_ref).unwrap_or(&[]),
};
fn local_impls(db: &dyn HirDatabase, module: ModuleId) -> Option<Arc<TraitImpls>> {
let block = module.containing_block()?;
hit!(block_local_impls);
db.trait_impls_in_block(block)
}
// Note: Since we're using impls_for_trait, only impls where the trait
// can be resolved should ever reach Chalk. impl_datum relies on that
// and will panic if the trait can't be resolved.
let in_deps = self.db.trait_impls_in_deps(self.krate);
let in_self = self.db.trait_impls_in_crate(self.krate);
let trait_module = trait_.module(self.db.upcast());
let type_module = match self_ty_fp {
Some(TyFingerprint::Adt(adt_id)) => Some(adt_id.module(self.db.upcast())),
Some(TyFingerprint::ForeignType(type_id)) => {
Some(from_foreign_def_id(type_id).module(self.db.upcast()))
}
Some(TyFingerprint::Dyn(trait_id)) => Some(trait_id.module(self.db.upcast())),
_ => None,
};
let impl_maps = [
Some(in_deps),
Some(in_self),
local_impls(self.db, trait_module),
type_module.and_then(|m| local_impls(self.db, m)),
];
let id_to_chalk = |id: hir_def::ImplId| id.to_chalk(self.db);
let result: Vec<_> = if fps.is_empty() {
debug!("Unrestricted search for {:?} impls...", trait_);
impl_maps
.iter()
.filter_map(|o| o.as_ref())
.flat_map(|impls| impls.for_trait(trait_).map(id_to_chalk))
.collect()
} else {
impl_maps
.iter()
.filter_map(|o| o.as_ref())
.flat_map(|impls| {
fps.iter().flat_map(move |fp| {
impls.for_trait_and_self_ty(trait_, *fp).map(id_to_chalk)
})
})
.collect()
};
debug!("impls_for_trait returned {} impls", result.len());
result
}
fn impl_provided_for(&self, auto_trait_id: TraitId, kind: &chalk_ir::TyKind<Interner>) -> bool {
debug!("impl_provided_for {:?}, {:?}", auto_trait_id, kind);
false // FIXME
}
fn associated_ty_value(&self, id: AssociatedTyValueId) -> Arc<AssociatedTyValue> {
self.db.associated_ty_value(self.krate, id)
}
fn custom_clauses(&self) -> Vec<chalk_ir::ProgramClause<Interner>> {
vec![]
}
fn local_impls_to_coherence_check(&self, _trait_id: TraitId) -> Vec<ImplId> {
// We don't do coherence checking (yet)
unimplemented!()
}
fn interner(&self) -> &Interner {
&Interner
}
fn well_known_trait_id(
&self,
well_known_trait: rust_ir::WellKnownTrait,
) -> Option<chalk_ir::TraitId<Interner>> {
let lang_attr = lang_attr_from_well_known_trait(well_known_trait);
let trait_ = match self.db.lang_item(self.krate, lang_attr.into()) {
Some(LangItemTarget::TraitId(trait_)) => trait_,
_ => return None,
};
Some(to_chalk_trait_id(trait_))
}
fn program_clauses_for_env(
&self,
environment: &chalk_ir::Environment<Interner>,
) -> chalk_ir::ProgramClauses<Interner> {
self.db.program_clauses_for_chalk_env(self.krate, environment.clone())
}
fn opaque_ty_data(&self, id: chalk_ir::OpaqueTyId<Interner>) -> Arc<OpaqueTyDatum> {
let full_id = self.db.lookup_intern_impl_trait_id(id.into());
let bound = match full_id {
crate::ImplTraitId::ReturnTypeImplTrait(func, idx) => {
let datas = self
.db
.return_type_impl_traits(func)
.expect("impl trait id without impl traits");
let (datas, binders) = (*datas).as_ref().into_value_and_skipped_binders();
let data = &datas.impl_traits[idx as usize];
let bound = OpaqueTyDatumBound {
bounds: make_only_type_binders(1, data.bounds.skip_binders().to_vec()),
where_clauses: make_only_type_binders(0, vec![]),
};
chalk_ir::Binders::new(binders, bound)
}
crate::ImplTraitId::AsyncBlockTypeImplTrait(..) => {
if let Some((future_trait, future_output)) = self
.db
.lang_item(self.krate, "future_trait".into())
.and_then(|item| item.as_trait())
.and_then(|trait_| {
let alias =
self.db.trait_data(trait_).associated_type_by_name(&name![Output])?;
Some((trait_, alias))
})
{
// Making up Symbols value as variable is void: AsyncBlock<T>:
//
// |--------------------OpaqueTyDatum-------------------|
// |-------------OpaqueTyDatumBound--------------|
// for<T> <Self> [Future<Self>, Future::Output<Self> = T]
// ^1 ^0 ^0 ^0 ^1
let impl_bound = WhereClause::Implemented(TraitRef {
trait_id: to_chalk_trait_id(future_trait),
// Self type as the first parameter.
substitution: Substitution::from1(
&Interner,
TyKind::BoundVar(BoundVar {
debruijn: DebruijnIndex::INNERMOST,
index: 0,
})
.intern(&Interner),
),
});
let proj_bound = WhereClause::AliasEq(AliasEq {
alias: AliasTy::Projection(ProjectionTy {
associated_ty_id: to_assoc_type_id(future_output),
// Self type as the first parameter.
substitution: Substitution::from1(
&Interner,
TyKind::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0))
.intern(&Interner),
),
}),
// The parameter of the opaque type.
ty: TyKind::BoundVar(BoundVar { debruijn: DebruijnIndex::ONE, index: 0 })
.intern(&Interner),
});
let bound = OpaqueTyDatumBound {
bounds: make_only_type_binders(
1,
vec![
crate::wrap_empty_binders(impl_bound),
crate::wrap_empty_binders(proj_bound),
],
),
where_clauses: make_only_type_binders(0, vec![]),
};
// The opaque type has 1 parameter.
make_only_type_binders(1, bound)
} else {
// If failed to find Symbols value as variable is void: Future::Output, return empty bounds as fallback.
let bound = OpaqueTyDatumBound {
bounds: make_only_type_binders(0, vec![]),
where_clauses: make_only_type_binders(0, vec![]),
};
// The opaque type has 1 parameter.
make_only_type_binders(1, bound)
}
}
};
Arc::new(OpaqueTyDatum { opaque_ty_id: id, bound })
}
fn hidden_opaque_type(&self, _id: chalk_ir::OpaqueTyId<Interner>) -> chalk_ir::Ty<Interner> {
// FIXME: actually provide the hidden type; it is relevant for auto traits
TyKind::Error.intern(&Interner)
}
fn is_object_safe(&self, _trait_id: chalk_ir::TraitId<Interner>) -> bool {
// FIXME: implement actual object safety
true
}
fn closure_kind(
&self,
_closure_id: chalk_ir::ClosureId<Interner>,
_substs: &chalk_ir::Substitution<Interner>,
) -> rust_ir::ClosureKind {
// Fn is the closure kind that implements all three traits
rust_ir::ClosureKind::Fn
}
fn closure_inputs_and_output(
&self,
_closure_id: chalk_ir::ClosureId<Interner>,
substs: &chalk_ir::Substitution<Interner>,
) -> chalk_ir::Binders<rust_ir::FnDefInputsAndOutputDatum<Interner>> {
let sig_ty = substs.at(&Interner, 0).assert_ty_ref(&Interner).clone();
let sig = &sig_ty.callable_sig(self.db).expect("first closure param should be fn ptr");
let io = rust_ir::FnDefInputsAndOutputDatum {
argument_types: sig.params().to_vec(),
return_type: sig.ret().clone(),
};
make_only_type_binders(0, io.shifted_in(&Interner))
}
fn closure_upvars(
&self,
_closure_id: chalk_ir::ClosureId<Interner>,
_substs: &chalk_ir::Substitution<Interner>,
) -> chalk_ir::Binders<chalk_ir::Ty<Interner>> {
let ty = TyBuilder::unit();
make_only_type_binders(0, ty)
}
fn closure_fn_substitution(
&self,
_closure_id: chalk_ir::ClosureId<Interner>,
_substs: &chalk_ir::Substitution<Interner>,
) -> chalk_ir::Substitution<Interner> {
Substitution::empty(&Interner)
}
fn trait_name(&self, trait_id: chalk_ir::TraitId<Interner>) -> String {
let id = from_chalk_trait_id(trait_id);
self.db.trait_data(id).name.to_string()
}
fn adt_name(&self, chalk_ir::AdtId(adt_id): AdtId) -> String {
match adt_id {
hir_def::AdtId::StructId(id) => self.db.struct_data(id).name.to_string(),
hir_def::AdtId::EnumId(id) => self.db.enum_data(id).name.to_string(),
hir_def::AdtId::UnionId(id) => self.db.union_data(id).name.to_string(),
}
}
fn assoc_type_name(&self, assoc_ty_id: chalk_ir::AssocTypeId<Interner>) -> String {
let id = self.db.associated_ty_data(assoc_ty_id).name;
self.db.type_alias_data(id).name.to_string()
}
fn opaque_type_name(&self, opaque_ty_id: chalk_ir::OpaqueTyId<Interner>) -> String {
format!("Opaque_{}", opaque_ty_id.0)
}
fn fn_def_name(&self, fn_def_id: chalk_ir::FnDefId<Interner>) -> String {
format!("fn_{}", fn_def_id.0)
}
fn generator_datum(
&self,
_: chalk_ir::GeneratorId<Interner>,
) -> std::sync::Arc<chalk_solve::rust_ir::GeneratorDatum<Interner>> {
// FIXME
unimplemented!()
}
fn generator_witness_datum(
&self,
_: chalk_ir::GeneratorId<Interner>,
) -> std::sync::Arc<chalk_solve::rust_ir::GeneratorWitnessDatum<Interner>> {
// FIXME
unimplemented!()
}
fn unification_database(&self) -> &dyn chalk_ir::UnificationDatabase<Interner> {
&self.db
}
}
impl<'a> chalk_ir::UnificationDatabase<Interner> for &'a dyn HirDatabase {
fn fn_def_variance(
&self,
fn_def_id: chalk_ir::FnDefId<Interner>,
) -> chalk_ir::Variances<Interner> {
HirDatabase::fn_def_variance(*self, fn_def_id)
}
fn adt_variance(&self, adt_id: chalk_ir::AdtId<Interner>) -> chalk_ir::Variances<Interner> {
HirDatabase::adt_variance(*self, adt_id)
}
}
pub(crate) fn program_clauses_for_chalk_env_query(
db: &dyn HirDatabase,
krate: CrateId,
environment: chalk_ir::Environment<Interner>,
) -> chalk_ir::ProgramClauses<Interner> {
chalk_solve::program_clauses_for_env(&ChalkContext { db, krate }, &environment)
}
pub(crate) fn associated_ty_data_query(
db: &dyn HirDatabase,
id: AssocTypeId,
) -> Arc<AssociatedTyDatum> {
debug!("associated_ty_data {:?}", id);
let type_alias: TypeAliasId = from_assoc_type_id(id);
let trait_ = match type_alias.lookup(db.upcast()).container {
AssocContainerId::TraitId(t) => t,
_ => panic!("associated type not in trait"),
};
// Lower bounds -- we could/should maybe move this to a separate query in `lower`
let type_alias_data = db.type_alias_data(type_alias);
let generic_params = generics(db.upcast(), type_alias.into());
// let bound_vars = generic_params.bound_vars_subst(DebruijnIndex::INNERMOST);
let resolver = hir_def::resolver::HasResolver::resolver(type_alias, db.upcast());
let ctx = crate::TyLoweringContext::new(db, &resolver)
.with_type_param_mode(crate::lower::TypeParamLoweringMode::Variable);
let self_ty =
TyKind::BoundVar(BoundVar::new(crate::DebruijnIndex::INNERMOST, 0)).intern(&Interner);
let mut bounds: Vec<_> = type_alias_data
.bounds
.iter()
.flat_map(|bound| ctx.lower_type_bound(bound, self_ty.clone(), false))
.filter_map(|pred| generic_predicate_to_inline_bound(db, &pred, &self_ty))
.collect();
if !ctx.unsized_types.borrow().contains(&self_ty) {
let sized_trait = resolver
.krate()
.and_then(|krate| db.lang_item(krate, "sized".into()))
.and_then(|lang_item| lang_item.as_trait().map(to_chalk_trait_id));
let sized_bound = sized_trait.into_iter().map(|sized_trait| {
let trait_bound =
rust_ir::TraitBound { trait_id: sized_trait, args_no_self: Default::default() };
let inline_bound = rust_ir::InlineBound::TraitBound(trait_bound);
chalk_ir::Binders::empty(&Interner, inline_bound)
});
bounds.extend(sized_bound);
bounds.shrink_to_fit();
}
// FIXME: Re-enable where clauses on associated types when an upstream chalk bug is fixed.
// (rust-analyzer#9052)
// let where_clauses = convert_where_clauses(db, type_alias.into(), &bound_vars);
let bound_data = rust_ir::AssociatedTyDatumBound { bounds, where_clauses: vec![] };
let datum = AssociatedTyDatum {
trait_id: to_chalk_trait_id(trait_),
id,
name: type_alias,
binders: make_only_type_binders(generic_params.len(), bound_data),
};
Arc::new(datum)
}
pub(crate) fn trait_datum_query(
db: &dyn HirDatabase,
krate: CrateId,
trait_id: TraitId,
) -> Arc<TraitDatum> {
debug!("trait_datum {:?}", trait_id);
let trait_ = from_chalk_trait_id(trait_id);
let trait_data = db.trait_data(trait_);
debug!("trait {:?} = {:?}", trait_id, trait_data.name);
let generic_params = generics(db.upcast(), trait_.into());
let bound_vars = generic_params.bound_vars_subst(DebruijnIndex::INNERMOST);
let flags = rust_ir::TraitFlags {
auto: trait_data.is_auto,
upstream: trait_.lookup(db.upcast()).container.krate() != krate,
non_enumerable: true,
coinductive: false, // only relevant for Chalk testing
// FIXME: set these flags correctly
marker: false,
fundamental: false,
};
let where_clauses = convert_where_clauses(db, trait_.into(), &bound_vars);
let associated_ty_ids = trait_data.associated_types().map(to_assoc_type_id).collect();
let trait_datum_bound = rust_ir::TraitDatumBound { where_clauses };
let well_known =
lang_attr(db.upcast(), trait_).and_then(|name| well_known_trait_from_lang_attr(&name));
let trait_datum = TraitDatum {
id: trait_id,
binders: make_only_type_binders(bound_vars.len(&Interner), trait_datum_bound),
flags,
associated_ty_ids,
well_known,
};
Arc::new(trait_datum)
}
fn well_known_trait_from_lang_attr(name: &str) -> Option<WellKnownTrait> {
Some(match name {
"sized" => WellKnownTrait::Sized,
"copy" => WellKnownTrait::Copy,
"clone" => WellKnownTrait::Clone,
"drop" => WellKnownTrait::Drop,
"fn_once" => WellKnownTrait::FnOnce,
"fn_mut" => WellKnownTrait::FnMut,
"fn" => WellKnownTrait::Fn,
"unsize" => WellKnownTrait::Unsize,
"coerce_unsized" => WellKnownTrait::CoerceUnsized,
"discriminant_kind" => WellKnownTrait::DiscriminantKind,
_ => return None,
})
}
fn lang_attr_from_well_known_trait(attr: WellKnownTrait) -> &'static str {
match attr {
WellKnownTrait::Sized => "sized",
WellKnownTrait::Copy => "copy",
WellKnownTrait::Clone => "clone",
WellKnownTrait::Drop => "drop",
WellKnownTrait::FnOnce => "fn_once",
WellKnownTrait::FnMut => "fn_mut",
WellKnownTrait::Fn => "fn",
WellKnownTrait::Unsize => "unsize",
WellKnownTrait::Unpin => "unpin",
WellKnownTrait::CoerceUnsized => "coerce_unsized",
WellKnownTrait::DiscriminantKind => "discriminant_kind",
WellKnownTrait::Generator => "generator",
}
}
pub(crate) fn struct_datum_query(
db: &dyn HirDatabase,
krate: CrateId,
struct_id: AdtId,
) -> Arc<StructDatum> {
debug!("struct_datum {:?}", struct_id);
let chalk_ir::AdtId(adt_id) = struct_id;
let num_params = generics(db.upcast(), adt_id.into()).len();
let upstream = adt_id.module(db.upcast()).krate() != krate;
let where_clauses = {
let generic_params = generics(db.upcast(), adt_id.into());
let bound_vars = generic_params.bound_vars_subst(DebruijnIndex::INNERMOST);
convert_where_clauses(db, adt_id.into(), &bound_vars)
};
let flags = rust_ir::AdtFlags {
upstream,
// FIXME set fundamental and phantom_data flags correctly
fundamental: false,
phantom_data: false,
};
// FIXME provide enum variants properly (for auto traits)
let variant = rust_ir::AdtVariantDatum {
fields: Vec::new(), // FIXME add fields (only relevant for auto traits),
};
let struct_datum_bound = rust_ir::AdtDatumBound { variants: vec![variant], where_clauses };
let struct_datum = StructDatum {
// FIXME set ADT kind
kind: rust_ir::AdtKind::Struct,
id: struct_id,
binders: make_only_type_binders(num_params, struct_datum_bound),
flags,
};
Arc::new(struct_datum)
}
pub(crate) fn impl_datum_query(
db: &dyn HirDatabase,
krate: CrateId,
impl_id: ImplId,
) -> Arc<ImplDatum> {
let _p = profile::span("impl_datum");
debug!("impl_datum {:?}", impl_id);
let impl_: hir_def::ImplId = from_chalk(db, impl_id);
impl_def_datum(db, krate, impl_id, impl_)
}
fn impl_def_datum(
db: &dyn HirDatabase,
krate: CrateId,
chalk_id: ImplId,
impl_id: hir_def::ImplId,
) -> Arc<ImplDatum> {
let trait_ref = db
.impl_trait(impl_id)
// ImplIds for impls where the trait ref can't be resolved should never reach Chalk
.expect("invalid impl passed to Chalk")
.into_value_and_skipped_binders()
.0;
let impl_data = db.impl_data(impl_id);
let generic_params = generics(db.upcast(), impl_id.into());
let bound_vars = generic_params.bound_vars_subst(DebruijnIndex::INNERMOST);
let trait_ = trait_ref.hir_trait_id();
let impl_type = if impl_id.lookup(db.upcast()).container.krate() == krate {
rust_ir::ImplType::Local
} else {
rust_ir::ImplType::External
};
let where_clauses = convert_where_clauses(db, impl_id.into(), &bound_vars);
let negative = impl_data.is_negative;
debug!(
"impl {:?}: {}{} where {:?}",
chalk_id,
if negative { "!" } else { "" },
trait_ref.display(db),
where_clauses
);
let polarity = if negative { rust_ir::Polarity::Negative } else { rust_ir::Polarity::Positive };
let impl_datum_bound = rust_ir::ImplDatumBound { trait_ref, where_clauses };
let trait_data = db.trait_data(trait_);
let associated_ty_value_ids = impl_data
.items
.iter()
.filter_map(|item| match item {
AssocItemId::TypeAliasId(type_alias) => Some(*type_alias),
_ => None,
})
.filter(|&type_alias| {
// don't include associated types that don't exist in the trait
let name = &db.type_alias_data(type_alias).name;
trait_data.associated_type_by_name(name).is_some()
})
.map(|type_alias| TypeAliasAsValue(type_alias).to_chalk(db))
.collect();
debug!("impl_datum: {:?}", impl_datum_bound);
let impl_datum = ImplDatum {
binders: make_only_type_binders(bound_vars.len(&Interner), impl_datum_bound),
impl_type,
polarity,
associated_ty_value_ids,
};
Arc::new(impl_datum)
}
pub(crate) fn associated_ty_value_query(
db: &dyn HirDatabase,
krate: CrateId,
id: AssociatedTyValueId,
) -> Arc<AssociatedTyValue> {
let type_alias: TypeAliasAsValue = from_chalk(db, id);
type_alias_associated_ty_value(db, krate, type_alias.0)
}
fn type_alias_associated_ty_value(
db: &dyn HirDatabase,
_krate: CrateId,
type_alias: TypeAliasId,
) -> Arc<AssociatedTyValue> {
let type_alias_data = db.type_alias_data(type_alias);
let impl_id = match type_alias.lookup(db.upcast()).container {
AssocContainerId::ImplId(it) => it,
_ => panic!("assoc ty value should be in impl"),
};
let trait_ref = db
.impl_trait(impl_id)
.expect("assoc ty value should not exist")
.into_value_and_skipped_binders()
.0; // we don't return any assoc ty values if the impl'd trait can't be resolved
let assoc_ty = db
.trait_data(trait_ref.hir_trait_id())
.associated_type_by_name(&type_alias_data.name)
.expect("assoc ty value should not exist"); // validated when building the impl data as well
let (ty, binders) = db.ty(type_alias.into()).into_value_and_skipped_binders();
let value_bound = rust_ir::AssociatedTyValueBound { ty };
let value = rust_ir::AssociatedTyValue {
impl_id: impl_id.to_chalk(db),
associated_ty_id: to_assoc_type_id(assoc_ty),
value: chalk_ir::Binders::new(binders, value_bound),
};
Arc::new(value)
}
pub(crate) fn fn_def_datum_query(
db: &dyn HirDatabase,
_krate: CrateId,
fn_def_id: FnDefId,
) -> Arc<FnDefDatum> {
let callable_def: CallableDefId = from_chalk(db, fn_def_id);
let generic_params = generics(db.upcast(), callable_def.into());
let (sig, binders) = db.callable_item_signature(callable_def).into_value_and_skipped_binders();
let bound_vars = generic_params.bound_vars_subst(DebruijnIndex::INNERMOST);
let where_clauses = convert_where_clauses(db, callable_def.into(), &bound_vars);
let bound = rust_ir::FnDefDatumBound {
// Note: Chalk doesn't actually use this information yet as far as I am aware, but we provide it anyway
inputs_and_output: make_only_type_binders(
0,
rust_ir::FnDefInputsAndOutputDatum {
argument_types: sig.params().to_vec(),
return_type: sig.ret().clone(),
}
.shifted_in(&Interner),
),
where_clauses,
};
let datum = FnDefDatum {
id: fn_def_id,
sig: chalk_ir::FnSig { abi: (), safety: chalk_ir::Safety::Safe, variadic: sig.is_varargs },
binders: chalk_ir::Binders::new(binders, bound),
};
Arc::new(datum)
}
pub(crate) fn fn_def_variance_query(db: &dyn HirDatabase, fn_def_id: FnDefId) -> Variances {
let callable_def: CallableDefId = from_chalk(db, fn_def_id);
let generic_params = generics(db.upcast(), callable_def.into());
Variances::from_iter(
&Interner,
std::iter::repeat(chalk_ir::Variance::Invariant).take(generic_params.len()),
)
}
pub(crate) fn adt_variance_query(
db: &dyn HirDatabase,
chalk_ir::AdtId(adt_id): AdtId,
) -> Variances {
let generic_params = generics(db.upcast(), adt_id.into());
Variances::from_iter(
&Interner,
std::iter::repeat(chalk_ir::Variance::Invariant).take(generic_params.len()),
)
}
pub(super) fn convert_where_clauses(
db: &dyn HirDatabase,
def: GenericDefId,
substs: &Substitution,
) -> Vec<chalk_ir::QuantifiedWhereClause<Interner>> {
let generic_predicates = db.generic_predicates(def);
let mut result = Vec::with_capacity(generic_predicates.len());
for pred in generic_predicates.iter() {
result.push(pred.clone().substitute(&Interner, substs));
}
result
}
pub(super) fn generic_predicate_to_inline_bound(
db: &dyn HirDatabase,
pred: &QuantifiedWhereClause,
self_ty: &Ty,
) -> Option<chalk_ir::Binders<rust_ir::InlineBound<Interner>>> {
// 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.
let self_ty_shifted_in = self_ty.clone().shifted_in_from(&Interner, DebruijnIndex::ONE);
let (pred, binders) = pred.as_ref().into_value_and_skipped_binders();
match pred {
WhereClause::Implemented(trait_ref) => {
if trait_ref.self_type_parameter(&Interner) != self_ty_shifted_in {
// we can only convert predicates back to type bounds if they
// have the expected self type
return None;
}
let args_no_self = trait_ref.substitution.as_slice(&Interner)[1..]
.iter()
.map(|ty| ty.clone().cast(&Interner))
.collect();
let trait_bound = rust_ir::TraitBound { trait_id: trait_ref.trait_id, args_no_self };
Some(chalk_ir::Binders::new(binders, rust_ir::InlineBound::TraitBound(trait_bound)))
}
WhereClause::AliasEq(AliasEq { alias: AliasTy::Projection(projection_ty), ty }) => {
if projection_ty.self_type_parameter(&Interner) != self_ty_shifted_in {
return None;
}
let trait_ = projection_ty.trait_(db);
let args_no_self = projection_ty.substitution.as_slice(&Interner)[1..]
.iter()
.map(|ty| ty.clone().cast(&Interner))
.collect();
let alias_eq_bound = rust_ir::AliasEqBound {
value: ty.clone(),
trait_bound: rust_ir::TraitBound {
trait_id: to_chalk_trait_id(trait_),
args_no_self,
},
associated_ty_id: projection_ty.associated_ty_id,
parameters: Vec::new(), // FIXME we don't support generic associated types yet
};
Some(chalk_ir::Binders::new(
binders,
rust_ir::InlineBound::AliasEqBound(alias_eq_bound),
))
}
_ => None,
}
}