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https://github.com/rust-lang/rust-analyzer
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8e8d2ffecb
If the first type parameter gets inferred, that's still not handled correctly; it'll require some more refactoring: E.g. if we have `Thing<T, F=fn() -> T>` and then instantiate `Thing<_>`, that gets turned into `Thing<_, fn() -> _>` before the `_` is instantiated into a type variable -- so afterwards, we have two type variables without any connection to each other.
1238 lines
50 KiB
Rust
1238 lines
50 KiB
Rust
//! Methods for lowering the HIR to types. There are two main cases here:
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//!
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//! - Lowering a type reference like `&usize` or `Option<foo::bar::Baz>` to a
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//! type: The entry point for this is `Ty::from_hir`.
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//! - Building the type for an item: This happens through the `type_for_def` query.
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//!
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//! This usually involves resolving names, collecting generic arguments etc.
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use std::iter;
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use std::sync::Arc;
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use smallvec::SmallVec;
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use hir_def::{
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adt::StructKind,
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builtin_type::BuiltinType,
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generics::{TypeParamProvenance, WherePredicate, WherePredicateTarget},
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path::{GenericArg, Path, PathSegment, PathSegments},
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resolver::{HasResolver, Resolver, TypeNs},
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type_ref::{TypeBound, TypeRef},
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AdtId, AssocContainerId, AssocItemId, ConstId, EnumId, EnumVariantId, FunctionId, GenericDefId,
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HasModule, ImplId, LocalFieldId, Lookup, StaticId, StructId, TraitId, TypeAliasId, TypeParamId,
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UnionId, VariantId,
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};
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use hir_expand::name::Name;
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use ra_arena::map::ArenaMap;
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use ra_db::CrateId;
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use test_utils::mark;
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use crate::{
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db::HirDatabase,
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primitive::{FloatTy, IntTy},
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utils::{
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all_super_trait_refs, associated_type_by_name_including_super_traits, generics,
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make_mut_slice, variant_data,
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},
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Binders, BoundVar, DebruijnIndex, FnSig, GenericPredicate, OpaqueTy, OpaqueTyId, PolyFnSig,
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ProjectionPredicate, ProjectionTy, ReturnTypeImplTrait, ReturnTypeImplTraits, Substs,
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TraitEnvironment, TraitRef, Ty, TypeCtor, TypeWalk,
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};
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#[derive(Debug)]
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pub struct TyLoweringContext<'a> {
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pub db: &'a dyn HirDatabase,
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pub resolver: &'a Resolver,
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in_binders: DebruijnIndex,
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/// Note: Conceptually, it's thinkable that we could be in a location where
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/// some type params should be represented as placeholders, and others
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/// should be converted to variables. I think in practice, this isn't
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/// possible currently, so this should be fine for now.
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pub type_param_mode: TypeParamLoweringMode,
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pub impl_trait_mode: ImplTraitLoweringMode,
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impl_trait_counter: std::cell::Cell<u16>,
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/// When turning `impl Trait` into opaque types, we have to collect the
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/// bounds at the same time to get the IDs correct (without becoming too
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/// complicated). I don't like using interior mutability (as for the
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/// counter), but I've tried and failed to make the lifetimes work for
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/// passing around a `&mut TyLoweringContext`. The core problem is that
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/// we're grouping the mutable data (the counter and this field) together
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/// with the immutable context (the references to the DB and resolver).
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/// Splitting this up would be a possible fix.
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opaque_type_data: std::cell::RefCell<Vec<ReturnTypeImplTrait>>,
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}
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impl<'a> TyLoweringContext<'a> {
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pub fn new(db: &'a dyn HirDatabase, resolver: &'a Resolver) -> Self {
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let impl_trait_counter = std::cell::Cell::new(0);
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let impl_trait_mode = ImplTraitLoweringMode::Disallowed;
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let type_param_mode = TypeParamLoweringMode::Placeholder;
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let in_binders = DebruijnIndex::INNERMOST;
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let opaque_type_data = std::cell::RefCell::new(Vec::new());
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Self {
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db,
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resolver,
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in_binders,
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impl_trait_mode,
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impl_trait_counter,
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type_param_mode,
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opaque_type_data,
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}
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}
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pub fn with_debruijn<T>(
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&self,
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debruijn: DebruijnIndex,
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f: impl FnOnce(&TyLoweringContext) -> T,
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) -> T {
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let opaque_ty_data_vec = self.opaque_type_data.replace(Vec::new());
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let new_ctx = Self {
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in_binders: debruijn,
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impl_trait_counter: std::cell::Cell::new(self.impl_trait_counter.get()),
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opaque_type_data: std::cell::RefCell::new(opaque_ty_data_vec),
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..*self
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};
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let result = f(&new_ctx);
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self.impl_trait_counter.set(new_ctx.impl_trait_counter.get());
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self.opaque_type_data.replace(new_ctx.opaque_type_data.into_inner());
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result
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}
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pub fn with_shifted_in<T>(
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&self,
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debruijn: DebruijnIndex,
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f: impl FnOnce(&TyLoweringContext) -> T,
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) -> T {
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self.with_debruijn(self.in_binders.shifted_in_from(debruijn), f)
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}
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pub fn with_impl_trait_mode(self, impl_trait_mode: ImplTraitLoweringMode) -> Self {
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Self { impl_trait_mode, ..self }
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}
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pub fn with_type_param_mode(self, type_param_mode: TypeParamLoweringMode) -> Self {
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Self { type_param_mode, ..self }
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}
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}
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#[derive(Copy, Clone, Debug, PartialEq, Eq)]
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pub enum ImplTraitLoweringMode {
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/// `impl Trait` gets lowered into an opaque type that doesn't unify with
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/// anything except itself. This is used in places where values flow 'out',
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/// i.e. for arguments of the function we're currently checking, and return
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/// types of functions we're calling.
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Opaque,
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/// `impl Trait` gets lowered into a type variable. Used for argument
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/// position impl Trait when inside the respective function, since it allows
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/// us to support that without Chalk.
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Param,
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/// `impl Trait` gets lowered into a variable that can unify with some
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/// type. This is used in places where values flow 'in', i.e. for arguments
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/// of functions we're calling, and the return type of the function we're
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/// currently checking.
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Variable,
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/// `impl Trait` is disallowed and will be an error.
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Disallowed,
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}
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#[derive(Copy, Clone, Debug, PartialEq, Eq)]
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pub enum TypeParamLoweringMode {
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Placeholder,
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Variable,
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}
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impl Ty {
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pub fn from_hir(ctx: &TyLoweringContext<'_>, type_ref: &TypeRef) -> Self {
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Ty::from_hir_ext(ctx, type_ref).0
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}
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pub fn from_hir_ext(ctx: &TyLoweringContext<'_>, type_ref: &TypeRef) -> (Self, Option<TypeNs>) {
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let mut res = None;
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let ty = match type_ref {
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TypeRef::Never => Ty::simple(TypeCtor::Never),
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TypeRef::Tuple(inner) => {
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let inner_tys: Arc<[Ty]> = inner.iter().map(|tr| Ty::from_hir(ctx, tr)).collect();
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Ty::apply(
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TypeCtor::Tuple { cardinality: inner_tys.len() as u16 },
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Substs(inner_tys),
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)
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}
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TypeRef::Path(path) => {
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let (ty, res_) = Ty::from_hir_path(ctx, path);
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res = res_;
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ty
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}
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TypeRef::RawPtr(inner, mutability) => {
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let inner_ty = Ty::from_hir(ctx, inner);
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Ty::apply_one(TypeCtor::RawPtr(*mutability), inner_ty)
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}
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TypeRef::Array(inner) => {
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let inner_ty = Ty::from_hir(ctx, inner);
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Ty::apply_one(TypeCtor::Array, inner_ty)
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}
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TypeRef::Slice(inner) => {
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let inner_ty = Ty::from_hir(ctx, inner);
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Ty::apply_one(TypeCtor::Slice, inner_ty)
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}
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TypeRef::Reference(inner, mutability) => {
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let inner_ty = Ty::from_hir(ctx, inner);
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Ty::apply_one(TypeCtor::Ref(*mutability), inner_ty)
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}
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TypeRef::Placeholder => Ty::Unknown,
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TypeRef::Fn(params) => {
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let sig = Substs(params.iter().map(|tr| Ty::from_hir(ctx, tr)).collect());
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Ty::apply(TypeCtor::FnPtr { num_args: sig.len() as u16 - 1 }, sig)
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}
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TypeRef::DynTrait(bounds) => {
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let self_ty = Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0));
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let predicates = ctx.with_shifted_in(DebruijnIndex::ONE, |ctx| {
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bounds
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.iter()
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.flat_map(|b| GenericPredicate::from_type_bound(ctx, b, self_ty.clone()))
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.collect()
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});
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Ty::Dyn(predicates)
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}
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TypeRef::ImplTrait(bounds) => {
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match ctx.impl_trait_mode {
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ImplTraitLoweringMode::Opaque => {
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let idx = ctx.impl_trait_counter.get();
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ctx.impl_trait_counter.set(idx + 1);
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assert!(idx as usize == ctx.opaque_type_data.borrow().len());
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// this dance is to make sure the data is in the right
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// place even if we encounter more opaque types while
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// lowering the bounds
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ctx.opaque_type_data
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.borrow_mut()
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.push(ReturnTypeImplTrait { bounds: Binders::new(1, Vec::new()) });
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// We don't want to lower the bounds inside the binders
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// we're currently in, because they don't end up inside
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// those binders. E.g. when we have `impl Trait<impl
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// OtherTrait<T>>`, the `impl OtherTrait<T>` can't refer
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// to the self parameter from `impl Trait`, and the
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// bounds aren't actually stored nested within each
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// other, but separately. So if the `T` refers to a type
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// parameter of the outer function, it's just one binder
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// away instead of two.
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let actual_opaque_type_data = ctx
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.with_debruijn(DebruijnIndex::INNERMOST, |ctx| {
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ReturnTypeImplTrait::from_hir(ctx, &bounds)
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});
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ctx.opaque_type_data.borrow_mut()[idx as usize] = actual_opaque_type_data;
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let func = match ctx.resolver.generic_def() {
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Some(GenericDefId::FunctionId(f)) => f,
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_ => panic!("opaque impl trait lowering in non-function"),
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};
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let impl_trait_id = OpaqueTyId::ReturnTypeImplTrait(func, idx);
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let generics = generics(ctx.db.upcast(), func.into());
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let parameters = Substs::bound_vars(&generics, ctx.in_binders);
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Ty::Opaque(OpaqueTy { opaque_ty_id: impl_trait_id, parameters })
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}
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ImplTraitLoweringMode::Param => {
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let idx = ctx.impl_trait_counter.get();
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// FIXME we're probably doing something wrong here
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ctx.impl_trait_counter.set(idx + count_impl_traits(type_ref) as u16);
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if let Some(def) = ctx.resolver.generic_def() {
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let generics = generics(ctx.db.upcast(), def);
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let param = generics
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.iter()
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.filter(|(_, data)| {
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data.provenance == TypeParamProvenance::ArgumentImplTrait
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})
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.nth(idx as usize)
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.map_or(Ty::Unknown, |(id, _)| Ty::Placeholder(id));
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param
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} else {
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Ty::Unknown
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}
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}
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ImplTraitLoweringMode::Variable => {
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let idx = ctx.impl_trait_counter.get();
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// FIXME we're probably doing something wrong here
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ctx.impl_trait_counter.set(idx + count_impl_traits(type_ref) as u16);
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let (parent_params, self_params, list_params, _impl_trait_params) =
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if let Some(def) = ctx.resolver.generic_def() {
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let generics = generics(ctx.db.upcast(), def);
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generics.provenance_split()
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} else {
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(0, 0, 0, 0)
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};
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Ty::Bound(BoundVar::new(
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ctx.in_binders,
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idx as usize + parent_params + self_params + list_params,
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))
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}
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ImplTraitLoweringMode::Disallowed => {
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// FIXME: report error
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Ty::Unknown
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}
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}
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}
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TypeRef::Error => Ty::Unknown,
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};
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(ty, res)
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}
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/// This is only for `generic_predicates_for_param`, where we can't just
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/// lower the self types of the predicates since that could lead to cycles.
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/// So we just check here if the `type_ref` resolves to a generic param, and which.
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fn from_hir_only_param(ctx: &TyLoweringContext<'_>, type_ref: &TypeRef) -> Option<TypeParamId> {
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let path = match type_ref {
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TypeRef::Path(path) => path,
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_ => return None,
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};
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if path.type_anchor().is_some() {
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return None;
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}
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if path.segments().len() > 1 {
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return None;
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}
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let resolution =
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match ctx.resolver.resolve_path_in_type_ns(ctx.db.upcast(), path.mod_path()) {
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Some((it, None)) => it,
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_ => return None,
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};
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if let TypeNs::GenericParam(param_id) = resolution {
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Some(param_id)
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} else {
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None
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}
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}
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pub(crate) fn from_type_relative_path(
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ctx: &TyLoweringContext<'_>,
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ty: Ty,
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// We need the original resolution to lower `Self::AssocTy` correctly
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res: Option<TypeNs>,
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remaining_segments: PathSegments<'_>,
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) -> (Ty, Option<TypeNs>) {
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if remaining_segments.len() == 1 {
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// resolve unselected assoc types
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let segment = remaining_segments.first().unwrap();
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(Ty::select_associated_type(ctx, res, segment), None)
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} else if remaining_segments.len() > 1 {
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// FIXME report error (ambiguous associated type)
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(Ty::Unknown, None)
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} else {
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(ty, res)
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}
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}
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pub(crate) fn from_partly_resolved_hir_path(
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ctx: &TyLoweringContext<'_>,
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resolution: TypeNs,
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resolved_segment: PathSegment<'_>,
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remaining_segments: PathSegments<'_>,
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infer_args: bool,
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) -> (Ty, Option<TypeNs>) {
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let ty = match resolution {
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TypeNs::TraitId(trait_) => {
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// if this is a bare dyn Trait, we'll directly put the required ^0 for the self type in there
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let self_ty = if remaining_segments.len() == 0 {
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Some(Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0)))
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} else {
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None
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};
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let trait_ref =
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TraitRef::from_resolved_path(ctx, trait_, resolved_segment, self_ty);
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let ty = if remaining_segments.len() == 1 {
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let segment = remaining_segments.first().unwrap();
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let found = associated_type_by_name_including_super_traits(
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ctx.db,
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trait_ref.clone(),
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&segment.name,
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);
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match found {
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Some((super_trait_ref, associated_ty)) => {
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// FIXME handle type parameters on the segment
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Ty::Projection(ProjectionTy {
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associated_ty,
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parameters: super_trait_ref.substs,
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})
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}
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None => {
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// FIXME: report error (associated type not found)
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Ty::Unknown
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}
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}
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} else if remaining_segments.len() > 1 {
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// FIXME report error (ambiguous associated type)
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Ty::Unknown
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} else {
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Ty::Dyn(Arc::new([GenericPredicate::Implemented(trait_ref)]))
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};
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return (ty, None);
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}
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TypeNs::GenericParam(param_id) => {
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let generics = generics(
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ctx.db.upcast(),
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ctx.resolver.generic_def().expect("generics in scope"),
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);
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match ctx.type_param_mode {
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TypeParamLoweringMode::Placeholder => Ty::Placeholder(param_id),
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TypeParamLoweringMode::Variable => {
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let idx = generics.param_idx(param_id).expect("matching generics");
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Ty::Bound(BoundVar::new(ctx.in_binders, idx))
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}
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}
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}
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TypeNs::SelfType(impl_id) => {
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let generics = generics(ctx.db.upcast(), impl_id.into());
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let substs = match ctx.type_param_mode {
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TypeParamLoweringMode::Placeholder => {
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Substs::type_params_for_generics(&generics)
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}
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TypeParamLoweringMode::Variable => {
|
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Substs::bound_vars(&generics, ctx.in_binders)
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}
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};
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ctx.db.impl_self_ty(impl_id).subst(&substs)
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}
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TypeNs::AdtSelfType(adt) => {
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let generics = generics(ctx.db.upcast(), adt.into());
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let substs = match ctx.type_param_mode {
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TypeParamLoweringMode::Placeholder => {
|
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Substs::type_params_for_generics(&generics)
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}
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TypeParamLoweringMode::Variable => {
|
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Substs::bound_vars(&generics, ctx.in_binders)
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}
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};
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ctx.db.ty(adt.into()).subst(&substs)
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}
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|
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TypeNs::AdtId(it) => {
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Ty::from_hir_path_inner(ctx, resolved_segment, it.into(), infer_args)
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}
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|
TypeNs::BuiltinType(it) => {
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|
Ty::from_hir_path_inner(ctx, resolved_segment, it.into(), infer_args)
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}
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|
TypeNs::TypeAliasId(it) => {
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|
Ty::from_hir_path_inner(ctx, resolved_segment, it.into(), infer_args)
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|
}
|
|
// FIXME: report error
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|
TypeNs::EnumVariantId(_) => return (Ty::Unknown, None),
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|
};
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Ty::from_type_relative_path(ctx, ty, Some(resolution), remaining_segments)
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|
}
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|
pub(crate) fn from_hir_path(ctx: &TyLoweringContext<'_>, path: &Path) -> (Ty, Option<TypeNs>) {
|
|
// Resolve the path (in type namespace)
|
|
if let Some(type_ref) = path.type_anchor() {
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let (ty, res) = Ty::from_hir_ext(ctx, &type_ref);
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|
return Ty::from_type_relative_path(ctx, ty, res, path.segments());
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|
}
|
|
let (resolution, remaining_index) =
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match ctx.resolver.resolve_path_in_type_ns(ctx.db.upcast(), path.mod_path()) {
|
|
Some(it) => it,
|
|
None => return (Ty::Unknown, None),
|
|
};
|
|
let (resolved_segment, remaining_segments) = match remaining_index {
|
|
None => (
|
|
path.segments().last().expect("resolved path has at least one element"),
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|
PathSegments::EMPTY,
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|
),
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|
Some(i) => (path.segments().get(i - 1).unwrap(), path.segments().skip(i)),
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|
};
|
|
Ty::from_partly_resolved_hir_path(
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ctx,
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resolution,
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resolved_segment,
|
|
remaining_segments,
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|
false,
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)
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|
}
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|
|
|
fn select_associated_type(
|
|
ctx: &TyLoweringContext<'_>,
|
|
res: Option<TypeNs>,
|
|
segment: PathSegment<'_>,
|
|
) -> Ty {
|
|
if let Some(res) = res {
|
|
let ty =
|
|
associated_type_shorthand_candidates(ctx.db, res, move |name, t, associated_ty| {
|
|
if name == segment.name {
|
|
let substs = match ctx.type_param_mode {
|
|
TypeParamLoweringMode::Placeholder => {
|
|
// if we're lowering to placeholders, we have to put
|
|
// them in now
|
|
let s = Substs::type_params(
|
|
ctx.db,
|
|
ctx.resolver.generic_def().expect(
|
|
"there should be generics if there's a generic param",
|
|
),
|
|
);
|
|
t.substs.clone().subst_bound_vars(&s)
|
|
}
|
|
TypeParamLoweringMode::Variable => t.substs.clone(),
|
|
};
|
|
// We need to shift in the bound vars, since
|
|
// associated_type_shorthand_candidates does not do that
|
|
let substs = substs.shift_bound_vars(ctx.in_binders);
|
|
// FIXME handle type parameters on the segment
|
|
return Some(Ty::Projection(ProjectionTy {
|
|
associated_ty,
|
|
parameters: substs,
|
|
}));
|
|
}
|
|
|
|
None
|
|
});
|
|
|
|
ty.unwrap_or(Ty::Unknown)
|
|
} else {
|
|
Ty::Unknown
|
|
}
|
|
}
|
|
|
|
fn from_hir_path_inner(
|
|
ctx: &TyLoweringContext<'_>,
|
|
segment: PathSegment<'_>,
|
|
typable: TyDefId,
|
|
infer_args: bool,
|
|
) -> Ty {
|
|
let generic_def = match typable {
|
|
TyDefId::BuiltinType(_) => None,
|
|
TyDefId::AdtId(it) => Some(it.into()),
|
|
TyDefId::TypeAliasId(it) => Some(it.into()),
|
|
};
|
|
let substs = substs_from_path_segment(ctx, segment, generic_def, infer_args);
|
|
ctx.db.ty(typable).subst(&substs)
|
|
}
|
|
|
|
/// Collect generic arguments from a path into a `Substs`. See also
|
|
/// `create_substs_for_ast_path` and `def_to_ty` in rustc.
|
|
pub(super) fn substs_from_path(
|
|
ctx: &TyLoweringContext<'_>,
|
|
path: &Path,
|
|
// Note that we don't call `db.value_type(resolved)` here,
|
|
// `ValueTyDefId` is just a convenient way to pass generics and
|
|
// special-case enum variants
|
|
resolved: ValueTyDefId,
|
|
infer_args: bool,
|
|
) -> Substs {
|
|
let last = path.segments().last().expect("path should have at least one segment");
|
|
let (segment, generic_def) = match resolved {
|
|
ValueTyDefId::FunctionId(it) => (last, Some(it.into())),
|
|
ValueTyDefId::StructId(it) => (last, Some(it.into())),
|
|
ValueTyDefId::ConstId(it) => (last, Some(it.into())),
|
|
ValueTyDefId::StaticId(_) => (last, None),
|
|
ValueTyDefId::EnumVariantId(var) => {
|
|
// the generic args for an enum variant may be either specified
|
|
// on the segment referring to the enum, or on the segment
|
|
// referring to the variant. So `Option::<T>::None` and
|
|
// `Option::None::<T>` are both allowed (though the former is
|
|
// preferred). See also `def_ids_for_path_segments` in rustc.
|
|
let len = path.segments().len();
|
|
let penultimate = if len >= 2 { path.segments().get(len - 2) } else { None };
|
|
let segment = match penultimate {
|
|
Some(segment) if segment.args_and_bindings.is_some() => segment,
|
|
_ => last,
|
|
};
|
|
(segment, Some(var.parent.into()))
|
|
}
|
|
};
|
|
substs_from_path_segment(ctx, segment, generic_def, infer_args)
|
|
}
|
|
}
|
|
|
|
fn substs_from_path_segment(
|
|
ctx: &TyLoweringContext<'_>,
|
|
segment: PathSegment<'_>,
|
|
def_generic: Option<GenericDefId>,
|
|
infer_args: bool,
|
|
) -> Substs {
|
|
let mut substs = Vec::new();
|
|
let def_generics = def_generic.map(|def| generics(ctx.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;
|
|
|
|
substs.extend(iter::repeat(Ty::Unknown).take(parent_params));
|
|
|
|
let mut had_explicit_args = false;
|
|
|
|
if let Some(generic_args) = &segment.args_and_bindings {
|
|
if !generic_args.has_self_type {
|
|
substs.extend(iter::repeat(Ty::Unknown).take(self_params));
|
|
}
|
|
let expected_num =
|
|
if generic_args.has_self_type { self_params + type_params } else { type_params };
|
|
let skip = if generic_args.has_self_type && self_params == 0 { 1 } else { 0 };
|
|
// if args are provided, it should be all of them, but we can't rely on that
|
|
for arg in generic_args.args.iter().skip(skip).take(expected_num) {
|
|
match arg {
|
|
GenericArg::Type(type_ref) => {
|
|
had_explicit_args = true;
|
|
let ty = Ty::from_hir(ctx, type_ref);
|
|
substs.push(ty);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// handle defaults. In expression or pattern path segments without
|
|
// explicitly specified type arguments, missing type arguments are inferred
|
|
// (i.e. defaults aren't used).
|
|
if !infer_args || had_explicit_args {
|
|
if let Some(def_generic) = def_generic {
|
|
let defaults = ctx.db.generic_defaults(def_generic);
|
|
assert_eq!(total_len, defaults.len());
|
|
|
|
for default_ty in defaults.iter().skip(substs.len()) {
|
|
// each default can depend on the previous parameters
|
|
let substs_so_far = Substs(substs.clone().into());
|
|
substs.push(default_ty.clone().subst(&substs_so_far));
|
|
}
|
|
}
|
|
}
|
|
|
|
// add placeholders for args that were not provided
|
|
// FIXME: emit diagnostics in contexts where this is not allowed
|
|
for _ in substs.len()..total_len {
|
|
substs.push(Ty::Unknown);
|
|
}
|
|
assert_eq!(substs.len(), total_len);
|
|
|
|
Substs(substs.into())
|
|
}
|
|
|
|
impl TraitRef {
|
|
fn from_path(
|
|
ctx: &TyLoweringContext<'_>,
|
|
path: &Path,
|
|
explicit_self_ty: Option<Ty>,
|
|
) -> Option<Self> {
|
|
let resolved =
|
|
match ctx.resolver.resolve_path_in_type_ns_fully(ctx.db.upcast(), path.mod_path())? {
|
|
TypeNs::TraitId(tr) => tr,
|
|
_ => return None,
|
|
};
|
|
let segment = path.segments().last().expect("path should have at least one segment");
|
|
Some(TraitRef::from_resolved_path(ctx, resolved, segment, explicit_self_ty))
|
|
}
|
|
|
|
pub(crate) fn from_resolved_path(
|
|
ctx: &TyLoweringContext<'_>,
|
|
resolved: TraitId,
|
|
segment: PathSegment<'_>,
|
|
explicit_self_ty: Option<Ty>,
|
|
) -> Self {
|
|
let mut substs = TraitRef::substs_from_path(ctx, segment, resolved);
|
|
if let Some(self_ty) = explicit_self_ty {
|
|
make_mut_slice(&mut substs.0)[0] = self_ty;
|
|
}
|
|
TraitRef { trait_: resolved, substs }
|
|
}
|
|
|
|
fn from_hir(
|
|
ctx: &TyLoweringContext<'_>,
|
|
type_ref: &TypeRef,
|
|
explicit_self_ty: Option<Ty>,
|
|
) -> Option<Self> {
|
|
let path = match type_ref {
|
|
TypeRef::Path(path) => path,
|
|
_ => return None,
|
|
};
|
|
TraitRef::from_path(ctx, path, explicit_self_ty)
|
|
}
|
|
|
|
fn substs_from_path(
|
|
ctx: &TyLoweringContext<'_>,
|
|
segment: PathSegment<'_>,
|
|
resolved: TraitId,
|
|
) -> Substs {
|
|
substs_from_path_segment(ctx, segment, Some(resolved.into()), false)
|
|
}
|
|
|
|
pub(crate) fn from_type_bound(
|
|
ctx: &TyLoweringContext<'_>,
|
|
bound: &TypeBound,
|
|
self_ty: Ty,
|
|
) -> Option<TraitRef> {
|
|
match bound {
|
|
TypeBound::Path(path) => TraitRef::from_path(ctx, path, Some(self_ty)),
|
|
TypeBound::Error => None,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl GenericPredicate {
|
|
pub(crate) fn from_where_predicate<'a>(
|
|
ctx: &'a TyLoweringContext<'a>,
|
|
where_predicate: &'a WherePredicate,
|
|
) -> impl Iterator<Item = GenericPredicate> + 'a {
|
|
let self_ty = match &where_predicate.target {
|
|
WherePredicateTarget::TypeRef(type_ref) => Ty::from_hir(ctx, type_ref),
|
|
WherePredicateTarget::TypeParam(param_id) => {
|
|
let generic_def = ctx.resolver.generic_def().expect("generics in scope");
|
|
let generics = generics(ctx.db.upcast(), generic_def);
|
|
let param_id = hir_def::TypeParamId { parent: generic_def, local_id: *param_id };
|
|
match ctx.type_param_mode {
|
|
TypeParamLoweringMode::Placeholder => Ty::Placeholder(param_id),
|
|
TypeParamLoweringMode::Variable => {
|
|
let idx = generics.param_idx(param_id).expect("matching generics");
|
|
Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, idx))
|
|
}
|
|
}
|
|
}
|
|
};
|
|
GenericPredicate::from_type_bound(ctx, &where_predicate.bound, self_ty)
|
|
}
|
|
|
|
pub(crate) fn from_type_bound<'a>(
|
|
ctx: &'a TyLoweringContext<'a>,
|
|
bound: &'a TypeBound,
|
|
self_ty: Ty,
|
|
) -> impl Iterator<Item = GenericPredicate> + 'a {
|
|
let trait_ref = TraitRef::from_type_bound(ctx, bound, self_ty);
|
|
iter::once(trait_ref.clone().map_or(GenericPredicate::Error, GenericPredicate::Implemented))
|
|
.chain(
|
|
trait_ref
|
|
.into_iter()
|
|
.flat_map(move |tr| assoc_type_bindings_from_type_bound(ctx, bound, tr)),
|
|
)
|
|
}
|
|
}
|
|
|
|
fn assoc_type_bindings_from_type_bound<'a>(
|
|
ctx: &'a TyLoweringContext<'a>,
|
|
bound: &'a TypeBound,
|
|
trait_ref: TraitRef,
|
|
) -> impl Iterator<Item = GenericPredicate> + 'a {
|
|
let last_segment = match bound {
|
|
TypeBound::Path(path) => path.segments().last(),
|
|
TypeBound::Error => None,
|
|
};
|
|
last_segment
|
|
.into_iter()
|
|
.flat_map(|segment| segment.args_and_bindings.into_iter())
|
|
.flat_map(|args_and_bindings| args_and_bindings.bindings.iter())
|
|
.flat_map(move |binding| {
|
|
let found = associated_type_by_name_including_super_traits(
|
|
ctx.db,
|
|
trait_ref.clone(),
|
|
&binding.name,
|
|
);
|
|
let (super_trait_ref, associated_ty) = match found {
|
|
None => return SmallVec::<[GenericPredicate; 1]>::new(),
|
|
Some(t) => t,
|
|
};
|
|
let projection_ty =
|
|
ProjectionTy { associated_ty, parameters: super_trait_ref.substs.clone() };
|
|
let mut preds = SmallVec::with_capacity(
|
|
binding.type_ref.as_ref().map_or(0, |_| 1) + binding.bounds.len(),
|
|
);
|
|
if let Some(type_ref) = &binding.type_ref {
|
|
let ty = Ty::from_hir(ctx, type_ref);
|
|
let projection_predicate =
|
|
ProjectionPredicate { projection_ty: projection_ty.clone(), ty };
|
|
preds.push(GenericPredicate::Projection(projection_predicate));
|
|
}
|
|
for bound in &binding.bounds {
|
|
preds.extend(GenericPredicate::from_type_bound(
|
|
ctx,
|
|
bound,
|
|
Ty::Projection(projection_ty.clone()),
|
|
));
|
|
}
|
|
preds
|
|
})
|
|
}
|
|
|
|
impl ReturnTypeImplTrait {
|
|
fn from_hir(ctx: &TyLoweringContext, bounds: &[TypeBound]) -> Self {
|
|
mark::hit!(lower_rpit);
|
|
let self_ty = Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0));
|
|
let predicates = ctx.with_shifted_in(DebruijnIndex::ONE, |ctx| {
|
|
bounds
|
|
.iter()
|
|
.flat_map(|b| GenericPredicate::from_type_bound(ctx, b, self_ty.clone()))
|
|
.collect()
|
|
});
|
|
ReturnTypeImplTrait { bounds: Binders::new(1, predicates) }
|
|
}
|
|
}
|
|
|
|
fn count_impl_traits(type_ref: &TypeRef) -> usize {
|
|
let mut count = 0;
|
|
type_ref.walk(&mut |type_ref| {
|
|
if matches!(type_ref, TypeRef::ImplTrait(_)) {
|
|
count += 1;
|
|
}
|
|
});
|
|
count
|
|
}
|
|
|
|
/// Build the signature of a callable item (function, struct or enum variant).
|
|
pub fn callable_item_sig(db: &dyn HirDatabase, def: CallableDef) -> PolyFnSig {
|
|
match def {
|
|
CallableDef::FunctionId(f) => fn_sig_for_fn(db, f),
|
|
CallableDef::StructId(s) => fn_sig_for_struct_constructor(db, s),
|
|
CallableDef::EnumVariantId(e) => fn_sig_for_enum_variant_constructor(db, e),
|
|
}
|
|
}
|
|
|
|
pub fn associated_type_shorthand_candidates<R>(
|
|
db: &dyn HirDatabase,
|
|
res: TypeNs,
|
|
mut cb: impl FnMut(&Name, &TraitRef, TypeAliasId) -> Option<R>,
|
|
) -> Option<R> {
|
|
let traits_from_env: Vec<_> = match res {
|
|
TypeNs::SelfType(impl_id) => match db.impl_trait(impl_id) {
|
|
None => vec![],
|
|
Some(trait_ref) => vec![trait_ref.value],
|
|
},
|
|
TypeNs::GenericParam(param_id) => {
|
|
let predicates = db.generic_predicates_for_param(param_id);
|
|
let mut traits_: Vec<_> = predicates
|
|
.iter()
|
|
.filter_map(|pred| match &pred.value {
|
|
GenericPredicate::Implemented(tr) => Some(tr.clone()),
|
|
_ => None,
|
|
})
|
|
.collect();
|
|
// Handle `Self::Type` referring to own associated type in trait definitions
|
|
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
|
|
{
|
|
let trait_ref = TraitRef {
|
|
trait_: trait_id,
|
|
substs: Substs::bound_vars(&generics, DebruijnIndex::INNERMOST),
|
|
};
|
|
traits_.push(trait_ref);
|
|
}
|
|
}
|
|
traits_
|
|
}
|
|
_ => vec![],
|
|
};
|
|
|
|
for t in traits_from_env.into_iter().flat_map(move |t| all_super_trait_refs(db, t)) {
|
|
let data = db.trait_data(t.trait_);
|
|
|
|
for (name, assoc_id) in &data.items {
|
|
match assoc_id {
|
|
AssocItemId::TypeAliasId(alias) => {
|
|
if let Some(result) = cb(name, &t, *alias) {
|
|
return Some(result);
|
|
}
|
|
}
|
|
AssocItemId::FunctionId(_) | AssocItemId::ConstId(_) => {}
|
|
}
|
|
}
|
|
}
|
|
|
|
None
|
|
}
|
|
|
|
/// Build the type of all specific fields of a struct or enum variant.
|
|
pub(crate) fn field_types_query(
|
|
db: &dyn HirDatabase,
|
|
variant_id: VariantId,
|
|
) -> Arc<ArenaMap<LocalFieldId, Binders<Ty>>> {
|
|
let var_data = variant_data(db.upcast(), variant_id);
|
|
let (resolver, def): (_, GenericDefId) = match variant_id {
|
|
VariantId::StructId(it) => (it.resolver(db.upcast()), it.into()),
|
|
VariantId::UnionId(it) => (it.resolver(db.upcast()), it.into()),
|
|
VariantId::EnumVariantId(it) => (it.parent.resolver(db.upcast()), it.parent.into()),
|
|
};
|
|
let generics = generics(db.upcast(), def);
|
|
let mut res = ArenaMap::default();
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
for (field_id, field_data) in var_data.fields().iter() {
|
|
res.insert(field_id, Binders::new(generics.len(), Ty::from_hir(&ctx, &field_data.type_ref)))
|
|
}
|
|
Arc::new(res)
|
|
}
|
|
|
|
/// This query exists only to be used when resolving short-hand associated types
|
|
/// like `T::Item`.
|
|
///
|
|
/// See the analogous query in rustc and its comment:
|
|
/// https://github.com/rust-lang/rust/blob/9150f844e2624eb013ec78ca08c1d416e6644026/src/librustc_typeck/astconv.rs#L46
|
|
/// This is a query mostly to handle cycles somewhat gracefully; e.g. the
|
|
/// following bounds are disallowed: `T: Foo<U::Item>, U: Foo<T::Item>`, but
|
|
/// these are fine: `T: Foo<U::Item>, U: Foo<()>`.
|
|
pub(crate) fn generic_predicates_for_param_query(
|
|
db: &dyn HirDatabase,
|
|
param_id: TypeParamId,
|
|
) -> Arc<[Binders<GenericPredicate>]> {
|
|
let resolver = param_id.parent.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let generics = generics(db.upcast(), param_id.parent);
|
|
resolver
|
|
.where_predicates_in_scope()
|
|
// we have to filter out all other predicates *first*, before attempting to lower them
|
|
.filter(|pred| match &pred.target {
|
|
WherePredicateTarget::TypeRef(type_ref) => {
|
|
Ty::from_hir_only_param(&ctx, type_ref) == Some(param_id)
|
|
}
|
|
WherePredicateTarget::TypeParam(local_id) => *local_id == param_id.local_id,
|
|
})
|
|
.flat_map(|pred| {
|
|
GenericPredicate::from_where_predicate(&ctx, pred)
|
|
.map(|p| Binders::new(generics.len(), p))
|
|
})
|
|
.collect()
|
|
}
|
|
|
|
pub(crate) fn generic_predicates_for_param_recover(
|
|
_db: &dyn HirDatabase,
|
|
_cycle: &[String],
|
|
_param_id: &TypeParamId,
|
|
) -> Arc<[Binders<GenericPredicate>]> {
|
|
Arc::new([])
|
|
}
|
|
|
|
impl TraitEnvironment {
|
|
pub fn lower(db: &dyn HirDatabase, resolver: &Resolver) -> Arc<TraitEnvironment> {
|
|
let ctx = TyLoweringContext::new(db, &resolver)
|
|
.with_type_param_mode(TypeParamLoweringMode::Placeholder);
|
|
let mut predicates = resolver
|
|
.where_predicates_in_scope()
|
|
.flat_map(|pred| GenericPredicate::from_where_predicate(&ctx, pred))
|
|
.collect::<Vec<_>>();
|
|
|
|
if let Some(def) = resolver.generic_def() {
|
|
let container: Option<AssocContainerId> = match def {
|
|
// FIXME: is there a function for this?
|
|
GenericDefId::FunctionId(f) => Some(f.lookup(db.upcast()).container),
|
|
GenericDefId::AdtId(_) => None,
|
|
GenericDefId::TraitId(_) => None,
|
|
GenericDefId::TypeAliasId(t) => Some(t.lookup(db.upcast()).container),
|
|
GenericDefId::ImplId(_) => None,
|
|
GenericDefId::EnumVariantId(_) => None,
|
|
GenericDefId::ConstId(c) => Some(c.lookup(db.upcast()).container),
|
|
};
|
|
if let Some(AssocContainerId::TraitId(trait_id)) = container {
|
|
// add `Self: Trait<T1, T2, ...>` to the environment in trait
|
|
// function default implementations (and hypothetical code
|
|
// inside consts or type aliases)
|
|
test_utils::mark::hit!(trait_self_implements_self);
|
|
let substs = Substs::type_params(db, trait_id);
|
|
let trait_ref = TraitRef { trait_: trait_id, substs };
|
|
let pred = GenericPredicate::Implemented(trait_ref);
|
|
|
|
predicates.push(pred);
|
|
}
|
|
}
|
|
|
|
Arc::new(TraitEnvironment { predicates })
|
|
}
|
|
}
|
|
|
|
/// Resolve the where clause(s) of an item with generics.
|
|
pub(crate) fn generic_predicates_query(
|
|
db: &dyn HirDatabase,
|
|
def: GenericDefId,
|
|
) -> Arc<[Binders<GenericPredicate>]> {
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let generics = generics(db.upcast(), def);
|
|
resolver
|
|
.where_predicates_in_scope()
|
|
.flat_map(|pred| {
|
|
GenericPredicate::from_where_predicate(&ctx, pred)
|
|
.map(|p| Binders::new(generics.len(), p))
|
|
})
|
|
.collect()
|
|
}
|
|
|
|
/// Resolve the default type params from generics
|
|
pub(crate) fn generic_defaults_query(
|
|
db: &dyn HirDatabase,
|
|
def: GenericDefId,
|
|
) -> Arc<[Binders<Ty>]> {
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let generic_params = generics(db.upcast(), def);
|
|
|
|
let defaults = generic_params
|
|
.iter()
|
|
.enumerate()
|
|
.map(|(idx, (_, p))| {
|
|
let mut ty = p.default.as_ref().map_or(Ty::Unknown, |t| Ty::from_hir(&ctx, t));
|
|
|
|
// Each default can only refer to previous parameters.
|
|
ty.walk_mut_binders(
|
|
&mut |ty, binders| match ty {
|
|
Ty::Bound(BoundVar { debruijn, index }) if *debruijn == binders => {
|
|
if *index >= idx {
|
|
// type variable default referring to parameter coming
|
|
// after it. This is forbidden (FIXME: report
|
|
// diagnostic)
|
|
*ty = Ty::Unknown;
|
|
}
|
|
}
|
|
_ => {}
|
|
},
|
|
DebruijnIndex::INNERMOST,
|
|
);
|
|
|
|
Binders::new(idx, ty)
|
|
})
|
|
.collect();
|
|
|
|
defaults
|
|
}
|
|
|
|
fn fn_sig_for_fn(db: &dyn HirDatabase, def: FunctionId) -> PolyFnSig {
|
|
let data = db.function_data(def);
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx_params = TyLoweringContext::new(db, &resolver)
|
|
.with_impl_trait_mode(ImplTraitLoweringMode::Variable)
|
|
.with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let params = data.params.iter().map(|tr| Ty::from_hir(&ctx_params, tr)).collect::<Vec<_>>();
|
|
let ctx_ret = TyLoweringContext::new(db, &resolver)
|
|
.with_impl_trait_mode(ImplTraitLoweringMode::Opaque)
|
|
.with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let ret = Ty::from_hir(&ctx_ret, &data.ret_type);
|
|
let generics = generics(db.upcast(), def.into());
|
|
let num_binders = generics.len();
|
|
Binders::new(num_binders, FnSig::from_params_and_return(params, ret))
|
|
}
|
|
|
|
/// Build the declared type of a function. This should not need to look at the
|
|
/// function body.
|
|
fn type_for_fn(db: &dyn HirDatabase, def: FunctionId) -> Binders<Ty> {
|
|
let generics = generics(db.upcast(), def.into());
|
|
let substs = Substs::bound_vars(&generics, DebruijnIndex::INNERMOST);
|
|
Binders::new(substs.len(), Ty::apply(TypeCtor::FnDef(def.into()), substs))
|
|
}
|
|
|
|
/// Build the declared type of a const.
|
|
fn type_for_const(db: &dyn HirDatabase, def: ConstId) -> Binders<Ty> {
|
|
let data = db.const_data(def);
|
|
let generics = generics(db.upcast(), def.into());
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
|
|
Binders::new(generics.len(), Ty::from_hir(&ctx, &data.type_ref))
|
|
}
|
|
|
|
/// Build the declared type of a static.
|
|
fn type_for_static(db: &dyn HirDatabase, def: StaticId) -> Binders<Ty> {
|
|
let data = db.static_data(def);
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx = TyLoweringContext::new(db, &resolver);
|
|
|
|
Binders::new(0, Ty::from_hir(&ctx, &data.type_ref))
|
|
}
|
|
|
|
/// Build the declared type of a static.
|
|
fn type_for_builtin(def: BuiltinType) -> Ty {
|
|
Ty::simple(match def {
|
|
BuiltinType::Char => TypeCtor::Char,
|
|
BuiltinType::Bool => TypeCtor::Bool,
|
|
BuiltinType::Str => TypeCtor::Str,
|
|
BuiltinType::Int(t) => TypeCtor::Int(IntTy::from(t).into()),
|
|
BuiltinType::Float(t) => TypeCtor::Float(FloatTy::from(t).into()),
|
|
})
|
|
}
|
|
|
|
fn fn_sig_for_struct_constructor(db: &dyn HirDatabase, def: StructId) -> PolyFnSig {
|
|
let struct_data = db.struct_data(def);
|
|
let fields = struct_data.variant_data.fields();
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let params =
|
|
fields.iter().map(|(_, field)| Ty::from_hir(&ctx, &field.type_ref)).collect::<Vec<_>>();
|
|
let ret = type_for_adt(db, def.into());
|
|
Binders::new(ret.num_binders, FnSig::from_params_and_return(params, ret.value))
|
|
}
|
|
|
|
/// Build the type of a tuple struct constructor.
|
|
fn type_for_struct_constructor(db: &dyn HirDatabase, def: StructId) -> Binders<Ty> {
|
|
let struct_data = db.struct_data(def);
|
|
if let StructKind::Unit = struct_data.variant_data.kind() {
|
|
return type_for_adt(db, def.into());
|
|
}
|
|
let generics = generics(db.upcast(), def.into());
|
|
let substs = Substs::bound_vars(&generics, DebruijnIndex::INNERMOST);
|
|
Binders::new(substs.len(), Ty::apply(TypeCtor::FnDef(def.into()), substs))
|
|
}
|
|
|
|
fn fn_sig_for_enum_variant_constructor(db: &dyn HirDatabase, def: EnumVariantId) -> PolyFnSig {
|
|
let enum_data = db.enum_data(def.parent);
|
|
let var_data = &enum_data.variants[def.local_id];
|
|
let fields = var_data.variant_data.fields();
|
|
let resolver = def.parent.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let params =
|
|
fields.iter().map(|(_, field)| Ty::from_hir(&ctx, &field.type_ref)).collect::<Vec<_>>();
|
|
let ret = type_for_adt(db, def.parent.into());
|
|
Binders::new(ret.num_binders, FnSig::from_params_and_return(params, ret.value))
|
|
}
|
|
|
|
/// Build the type of a tuple enum variant constructor.
|
|
fn type_for_enum_variant_constructor(db: &dyn HirDatabase, def: EnumVariantId) -> Binders<Ty> {
|
|
let enum_data = db.enum_data(def.parent);
|
|
let var_data = &enum_data.variants[def.local_id].variant_data;
|
|
if let StructKind::Unit = var_data.kind() {
|
|
return type_for_adt(db, def.parent.into());
|
|
}
|
|
let generics = generics(db.upcast(), def.parent.into());
|
|
let substs = Substs::bound_vars(&generics, DebruijnIndex::INNERMOST);
|
|
Binders::new(substs.len(), Ty::apply(TypeCtor::FnDef(def.into()), substs))
|
|
}
|
|
|
|
fn type_for_adt(db: &dyn HirDatabase, adt: AdtId) -> Binders<Ty> {
|
|
let generics = generics(db.upcast(), adt.into());
|
|
let substs = Substs::bound_vars(&generics, DebruijnIndex::INNERMOST);
|
|
Binders::new(substs.len(), Ty::apply(TypeCtor::Adt(adt), substs))
|
|
}
|
|
|
|
fn type_for_type_alias(db: &dyn HirDatabase, t: TypeAliasId) -> Binders<Ty> {
|
|
let generics = generics(db.upcast(), t.into());
|
|
let resolver = t.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let type_ref = &db.type_alias_data(t).type_ref;
|
|
let substs = Substs::bound_vars(&generics, DebruijnIndex::INNERMOST);
|
|
let inner = Ty::from_hir(&ctx, type_ref.as_ref().unwrap_or(&TypeRef::Error));
|
|
Binders::new(substs.len(), inner)
|
|
}
|
|
|
|
#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
|
|
pub enum CallableDef {
|
|
FunctionId(FunctionId),
|
|
StructId(StructId),
|
|
EnumVariantId(EnumVariantId),
|
|
}
|
|
impl_froms!(CallableDef: FunctionId, StructId, EnumVariantId);
|
|
|
|
impl CallableDef {
|
|
pub fn krate(self, db: &dyn HirDatabase) -> CrateId {
|
|
let db = db.upcast();
|
|
match self {
|
|
CallableDef::FunctionId(f) => f.lookup(db).module(db),
|
|
CallableDef::StructId(s) => s.lookup(db).container.module(db),
|
|
CallableDef::EnumVariantId(e) => e.parent.lookup(db).container.module(db),
|
|
}
|
|
.krate
|
|
}
|
|
}
|
|
|
|
impl From<CallableDef> for GenericDefId {
|
|
fn from(def: CallableDef) -> GenericDefId {
|
|
match def {
|
|
CallableDef::FunctionId(f) => f.into(),
|
|
CallableDef::StructId(s) => s.into(),
|
|
CallableDef::EnumVariantId(e) => e.into(),
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
|
|
pub enum TyDefId {
|
|
BuiltinType(BuiltinType),
|
|
AdtId(AdtId),
|
|
TypeAliasId(TypeAliasId),
|
|
}
|
|
impl_froms!(TyDefId: BuiltinType, AdtId(StructId, EnumId, UnionId), TypeAliasId);
|
|
|
|
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
|
|
pub enum ValueTyDefId {
|
|
FunctionId(FunctionId),
|
|
StructId(StructId),
|
|
EnumVariantId(EnumVariantId),
|
|
ConstId(ConstId),
|
|
StaticId(StaticId),
|
|
}
|
|
impl_froms!(ValueTyDefId: FunctionId, StructId, EnumVariantId, ConstId, StaticId);
|
|
|
|
/// Build the declared type of an item. This depends on the namespace; e.g. for
|
|
/// `struct Foo(usize)`, we have two types: The type of the struct itself, and
|
|
/// the constructor function `(usize) -> Foo` which lives in the values
|
|
/// namespace.
|
|
pub(crate) fn ty_query(db: &dyn HirDatabase, def: TyDefId) -> Binders<Ty> {
|
|
match def {
|
|
TyDefId::BuiltinType(it) => Binders::new(0, type_for_builtin(it)),
|
|
TyDefId::AdtId(it) => type_for_adt(db, it),
|
|
TyDefId::TypeAliasId(it) => type_for_type_alias(db, it),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn ty_recover(db: &dyn HirDatabase, _cycle: &[String], def: &TyDefId) -> Binders<Ty> {
|
|
let num_binders = match *def {
|
|
TyDefId::BuiltinType(_) => 0,
|
|
TyDefId::AdtId(it) => generics(db.upcast(), it.into()).len(),
|
|
TyDefId::TypeAliasId(it) => generics(db.upcast(), it.into()).len(),
|
|
};
|
|
Binders::new(num_binders, Ty::Unknown)
|
|
}
|
|
|
|
pub(crate) fn value_ty_query(db: &dyn HirDatabase, def: ValueTyDefId) -> Binders<Ty> {
|
|
match def {
|
|
ValueTyDefId::FunctionId(it) => type_for_fn(db, it),
|
|
ValueTyDefId::StructId(it) => type_for_struct_constructor(db, it),
|
|
ValueTyDefId::EnumVariantId(it) => type_for_enum_variant_constructor(db, it),
|
|
ValueTyDefId::ConstId(it) => type_for_const(db, it),
|
|
ValueTyDefId::StaticId(it) => type_for_static(db, it),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn impl_self_ty_query(db: &dyn HirDatabase, impl_id: ImplId) -> Binders<Ty> {
|
|
let impl_data = db.impl_data(impl_id);
|
|
let resolver = impl_id.resolver(db.upcast());
|
|
let generics = generics(db.upcast(), impl_id.into());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
Binders::new(generics.len(), Ty::from_hir(&ctx, &impl_data.target_type))
|
|
}
|
|
|
|
pub(crate) fn impl_self_ty_recover(
|
|
db: &dyn HirDatabase,
|
|
_cycle: &[String],
|
|
impl_id: &ImplId,
|
|
) -> Binders<Ty> {
|
|
let generics = generics(db.upcast(), (*impl_id).into());
|
|
Binders::new(generics.len(), Ty::Unknown)
|
|
}
|
|
|
|
pub(crate) fn impl_trait_query(db: &dyn HirDatabase, impl_id: ImplId) -> Option<Binders<TraitRef>> {
|
|
let impl_data = db.impl_data(impl_id);
|
|
let resolver = impl_id.resolver(db.upcast());
|
|
let ctx =
|
|
TyLoweringContext::new(db, &resolver).with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let self_ty = db.impl_self_ty(impl_id);
|
|
let target_trait = impl_data.target_trait.as_ref()?;
|
|
Some(Binders::new(
|
|
self_ty.num_binders,
|
|
TraitRef::from_hir(&ctx, target_trait, Some(self_ty.value))?,
|
|
))
|
|
}
|
|
|
|
pub(crate) fn return_type_impl_traits(
|
|
db: &impl HirDatabase,
|
|
def: hir_def::FunctionId,
|
|
) -> Option<Arc<Binders<ReturnTypeImplTraits>>> {
|
|
// FIXME unify with fn_sig_for_fn instead of doing lowering twice, maybe
|
|
let data = db.function_data(def);
|
|
let resolver = def.resolver(db.upcast());
|
|
let ctx_ret = TyLoweringContext::new(db, &resolver)
|
|
.with_impl_trait_mode(ImplTraitLoweringMode::Opaque)
|
|
.with_type_param_mode(TypeParamLoweringMode::Variable);
|
|
let _ret = Ty::from_hir(&ctx_ret, &data.ret_type);
|
|
let generics = generics(db.upcast(), def.into());
|
|
let num_binders = generics.len();
|
|
let return_type_impl_traits =
|
|
ReturnTypeImplTraits { impl_traits: ctx_ret.opaque_type_data.into_inner() };
|
|
if return_type_impl_traits.impl_traits.is_empty() {
|
|
None
|
|
} else {
|
|
Some(Arc::new(Binders::new(num_binders, return_type_impl_traits)))
|
|
}
|
|
}
|