Lower impl trait to variables, move away from using placeholders where they don't belong

This commit is contained in:
Florian Diebold 2020-01-25 23:38:33 +01:00 committed by Florian Diebold
parent 93aa166748
commit 16c6937447
9 changed files with 220 additions and 188 deletions

View file

@ -12,8 +12,8 @@ use ra_prof::profile;
use crate::{
method_resolution::CrateImplBlocks,
traits::{chalk, AssocTyValue, Impl},
CallableDef, FnSig, GenericPredicate, InferenceResult, Substs, TraitRef, Ty, TyDefId, TypeCtor,
ValueTyDefId,
CallableDef, PolyFnSig, GenericPredicate, InferenceResult, Substs, TraitRef, Ty, TyDefId, TypeCtor,
ValueTyDefId, Binders,
};
#[salsa::query_group(HirDatabaseStorage)]
@ -27,14 +27,14 @@ pub trait HirDatabase: DefDatabase {
#[salsa::invoke(crate::lower::ty_query)]
#[salsa::cycle(crate::lower::ty_recover)]
fn ty(&self, def: TyDefId) -> Ty;
fn ty(&self, def: TyDefId) -> Binders<Ty>;
#[salsa::invoke(crate::lower::value_ty_query)]
fn value_ty(&self, def: ValueTyDefId) -> Ty;
fn value_ty(&self, def: ValueTyDefId) -> Binders<Ty>;
#[salsa::invoke(crate::lower::impl_self_ty_query)]
#[salsa::cycle(crate::lower::impl_self_ty_recover)]
fn impl_self_ty(&self, def: ImplId) -> Ty;
fn impl_self_ty(&self, def: ImplId) -> Binders<Ty>;
#[salsa::invoke(crate::lower::impl_trait_query)]
fn impl_trait(&self, def: ImplId) -> Option<TraitRef>;
@ -43,7 +43,7 @@ pub trait HirDatabase: DefDatabase {
fn field_types(&self, var: VariantId) -> Arc<ArenaMap<LocalStructFieldId, Ty>>;
#[salsa::invoke(crate::callable_item_sig)]
fn callable_item_signature(&self, def: CallableDef) -> FnSig;
fn callable_item_signature(&self, def: CallableDef) -> PolyFnSig;
#[salsa::invoke(crate::lower::generic_predicates_for_param_query)]
#[salsa::cycle(crate::lower::generic_predicates_for_param_recover)]

View file

@ -279,11 +279,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
impl_trait_mode: ImplTraitLoweringMode,
) -> Ty {
// FIXME use right resolver for block
let ctx = crate::lower::TyLoweringContext {
db: self.db,
resolver: &self.resolver,
impl_trait_mode,
};
let ctx = crate::lower::TyLoweringContext::new(self.db, &self.resolver).with_impl_trait_mode(impl_trait_mode);
let ty = Ty::from_hir(&ctx, type_ref);
let ty = self.insert_type_vars(ty);
self.normalize_associated_types_in(ty)
@ -457,24 +453,20 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
None => return (Ty::Unknown, None),
};
let resolver = &self.resolver;
let ctx = crate::lower::TyLoweringContext {
db: self.db,
resolver: &self.resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = crate::lower::TyLoweringContext::new(self.db, &self.resolver);
// FIXME: this should resolve assoc items as well, see this example:
// https://play.rust-lang.org/?gist=087992e9e22495446c01c0d4e2d69521
match resolver.resolve_path_in_type_ns_fully(self.db, path.mod_path()) {
Some(TypeNs::AdtId(AdtId::StructId(strukt))) => {
let substs = Ty::substs_from_path(&ctx, path, strukt.into());
let ty = self.db.ty(strukt.into());
let ty = self.insert_type_vars(ty.apply_substs(substs));
let ty = self.insert_type_vars(ty.subst(&substs));
(ty, Some(strukt.into()))
}
Some(TypeNs::EnumVariantId(var)) => {
let substs = Ty::substs_from_path(&ctx, path, var.into());
let ty = self.db.ty(var.parent.into());
let ty = self.insert_type_vars(ty.apply_substs(substs));
let ty = self.insert_type_vars(ty.subst(&substs));
(ty, Some(var.into()))
}
Some(_) | None => (Ty::Unknown, None),
@ -492,7 +484,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
self.infer_pat(*pat, &ty, BindingMode::default());
}
let return_ty = self.make_ty_with_mode(&data.ret_type, ImplTraitLoweringMode::Placeholder);
let return_ty = self.make_ty_with_mode(&data.ret_type, ImplTraitLoweringMode::Variable);
self.return_ty = self.insert_vars_for_impl_trait(return_ty);
}

View file

@ -20,7 +20,7 @@ use crate::{
traits::InEnvironment,
utils::{generics, variant_data, Generics},
ApplicationTy, CallableDef, InferTy, IntTy, Mutability, Obligation, Substs, TraitRef, Ty,
TypeCtor, TypeWalk, Uncertain,
TypeCtor, TypeWalk, Uncertain, Binders,
};
use super::{BindingMode, Expectation, InferenceContext, InferenceDiagnostic, TypeMismatch};
@ -588,10 +588,10 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
self.write_method_resolution(tgt_expr, func);
(ty, self.db.value_ty(func.into()), Some(generics(self.db, func.into())))
}
None => (receiver_ty, Ty::Unknown, None),
None => (receiver_ty, Binders::new(0, Ty::Unknown), None),
};
let substs = self.substs_for_method_call(def_generics, generic_args, &derefed_receiver_ty);
let method_ty = method_ty.apply_substs(substs);
let method_ty = method_ty.subst(&substs);
let method_ty = self.insert_type_vars(method_ty);
self.register_obligations_for_call(&method_ty);
let (expected_receiver_ty, param_tys, ret_ty) = match method_ty.callable_sig(self.db) {

View file

@ -10,8 +10,8 @@ use hir_def::{
use hir_expand::name::Name;
use crate::{
db::HirDatabase, lower::ImplTraitLoweringMode, method_resolution, Substs, Ty, TypeWalk,
ValueTyDefId,
db::HirDatabase, method_resolution, Substs, Ty,
ValueTyDefId
};
use super::{ExprOrPatId, InferenceContext, TraitRef};
@ -42,11 +42,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
}
let ty = self.make_ty(type_ref);
let remaining_segments_for_ty = path.segments().take(path.segments().len() - 1);
let ctx = crate::lower::TyLoweringContext {
db: self.db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = crate::lower::TyLoweringContext::new(self.db, &resolver);
let ty = Ty::from_type_relative_path(&ctx, ty, remaining_segments_for_ty);
self.resolve_ty_assoc_item(
ty,
@ -77,17 +73,16 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
ValueNs::EnumVariantId(it) => it.into(),
};
let mut ty = self.db.value_ty(typable);
if let Some(self_subst) = self_subst {
ty = ty.subst(&self_subst);
}
let ctx = crate::lower::TyLoweringContext {
db: self.db,
resolver: &self.resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ty = self.db.value_ty(typable);
// self_subst is just for the parent
let parent_substs = self_subst.unwrap_or_else(Substs::empty);
let ctx = crate::lower::TyLoweringContext::new(self.db, &self.resolver);
let substs = Ty::substs_from_path(&ctx, path, typable);
let ty = ty.subst(&substs);
let full_substs = Substs::builder(substs.len())
.use_parent_substs(&parent_substs)
.fill(substs.0[parent_substs.len()..].iter().cloned())
.build();
let ty = ty.subst(&full_substs);
Some(ty)
}
@ -111,11 +106,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
(TypeNs::TraitId(trait_), true) => {
let segment =
remaining_segments.last().expect("there should be at least one segment here");
let ctx = crate::lower::TyLoweringContext {
db: self.db,
resolver: &self.resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = crate::lower::TyLoweringContext::new(self.db, &self.resolver);
let trait_ref =
TraitRef::from_resolved_path(&ctx, trait_.into(), resolved_segment, None);
self.resolve_trait_assoc_item(trait_ref, segment, id)
@ -127,11 +118,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
// as Iterator>::Item::default`)
let remaining_segments_for_ty =
remaining_segments.take(remaining_segments.len() - 1);
let ctx = crate::lower::TyLoweringContext {
db: self.db,
resolver: &self.resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = crate::lower::TyLoweringContext::new(self.db, &self.resolver);
let ty = Ty::from_partly_resolved_hir_path(
&ctx,
def,
@ -235,12 +222,8 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
.fill(iter::repeat_with(|| self.table.new_type_var()))
.build();
let impl_self_ty = self.db.impl_self_ty(impl_id).subst(&impl_substs);
let substs = Substs::build_for_def(self.db, item)
.use_parent_substs(&impl_substs)
.fill_with_params()
.build();
self.unify(&impl_self_ty, &ty);
Some(substs)
Some(impl_substs)
}
AssocContainerId::TraitId(trait_) => {
// we're picking this method
@ -248,15 +231,11 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
.push(ty.clone())
.fill(std::iter::repeat_with(|| self.table.new_type_var()))
.build();
let substs = Substs::build_for_def(self.db, item)
.use_parent_substs(&trait_substs)
.fill_with_params()
.build();
self.obligations.push(super::Obligation::Trait(TraitRef {
trait_,
substs: trait_substs,
substs: trait_substs.clone(),
}));
Some(substs)
Some(trait_substs)
}
AssocContainerId::ContainerId(_) => None,
};

View file

@ -453,6 +453,30 @@ impl Deref for Substs {
}
}
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub struct Binders<T> {
pub num_binders: usize,
pub value: T,
}
impl<T> Binders<T> {
pub fn new(num_binders: usize, value: T) -> Self { Self { num_binders, value } }
}
impl<T: TypeWalk> Binders<T> {
/// Substitutes all variables.
pub fn subst(self, subst: &Substs) -> T {
assert_eq!(subst.len(), self.num_binders);
self.value.subst_bound_vars(subst)
}
/// Substitutes just a prefix of the variables (shifting the rest).
pub fn subst_prefix(self, subst: &Substs) -> Binders<T> {
assert!(subst.len() < self.num_binders);
Binders::new(self.num_binders - subst.len(), self.value.subst_bound_vars(subst))
}
}
/// A trait with type parameters. This includes the `Self`, so this represents a concrete type implementing the trait.
/// Name to be bikeshedded: TraitBound? TraitImplements?
#[derive(Clone, PartialEq, Eq, Debug, Hash)]
@ -553,6 +577,9 @@ pub struct FnSig {
params_and_return: Arc<[Ty]>,
}
/// A polymorphic function signature.
pub type PolyFnSig = Binders<FnSig>;
impl FnSig {
pub fn from_params_and_return(mut params: Vec<Ty>, ret: Ty) -> FnSig {
params.push(ret);
@ -757,6 +784,9 @@ pub trait TypeWalk {
&mut Ty::Bound(idx) => {
if idx as usize >= binders && (idx as usize - binders) < substs.len() {
*ty = substs.0[idx as usize - binders].clone();
} else if idx as usize >= binders + substs.len() {
// shift free binders
*ty = Ty::Bound(idx - substs.len() as u32);
}
}
_ => {}
@ -903,8 +933,8 @@ impl HirDisplay for ApplicationTy {
write!(f, ">")?;
}
write!(f, "(")?;
f.write_joined(sig.params(), ", ")?;
write!(f, ") -> {}", sig.ret().display(f.db))?;
f.write_joined(sig.value.params(), ", ")?;
write!(f, ") -> {}", sig.value.ret().display(f.db))?;
}
TypeCtor::Adt(def_id) => {
let name = match def_id {

View file

@ -28,32 +28,62 @@ use crate::{
variant_data,
},
FnSig, GenericPredicate, ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, TraitRef,
Ty, TypeCtor, TypeWalk,
Ty, TypeCtor, PolyFnSig, Binders,
};
#[derive(Clone, Debug)]
#[derive(Debug)]
pub struct TyLoweringContext<'a, DB: HirDatabase> {
pub db: &'a DB,
pub resolver: &'a Resolver,
/// Note: Conceptually, it's thinkable that we could be in a location where
/// some type params are quantified universally (and should be represented
/// as placeholders), and others are quantified existentially (and should be
/// converted to variables). I think in practice, this isn't possible
/// currently, so this should be fine for now.
pub type_param_mode: TypeParamLoweringMode,
pub impl_trait_mode: ImplTraitLoweringMode,
pub impl_trait_counter: std::cell::Cell<u16>,
}
#[derive(Clone, Debug)]
impl<'a, DB: HirDatabase> TyLoweringContext<'a, DB> {
pub fn new(db: &'a DB, resolver: &'a Resolver) -> Self {
let impl_trait_counter = std::cell::Cell::new(0);
let impl_trait_mode = ImplTraitLoweringMode::Disallowed;
let type_param_mode = TypeParamLoweringMode::Placeholder;
Self { db, resolver, impl_trait_mode, impl_trait_counter, type_param_mode }
}
pub fn with_impl_trait_mode(self, impl_trait_mode: ImplTraitLoweringMode) -> Self {
Self { impl_trait_mode, ..self }
}
pub fn with_type_param_mode(self, type_param_mode: TypeParamLoweringMode) -> Self {
Self { type_param_mode, ..self }
}
}
#[derive(Copy, Clone, Debug)]
pub enum ImplTraitLoweringMode {
/// `impl Trait` gets lowered into an opaque type that doesn't unify with
/// anything except itself. This is used in places where values flow 'out',
/// i.e. for arguments of the function we're currently checking, and return
/// types of functions we're calling.
Opaque,
/// `impl Trait` gets lowered into a placeholder that can unify with some
/// `impl Trait` gets lowered into a variable that can unify with some
/// type. This is used in places where values flow 'in', i.e. for arguments
/// of functions we're calling, and the return type of the function we're
/// currently checking.
Placeholder,
Variable,
/// `impl Trait` is disallowed and will be an error.
Disallowed,
}
#[derive(Copy, Clone, Debug)]
pub enum TypeParamLoweringMode {
Placeholder,
Variable,
}
impl Ty {
pub fn from_hir(ctx: &TyLoweringContext<'_, impl HirDatabase>, type_ref: &TypeRef) -> Self {
match type_ref {
@ -101,17 +131,25 @@ impl Ty {
let self_ty = Ty::Bound(0);
let predicates = bounds
.iter()
.flat_map(|b| GenericPredicate::from_type_bound(ctx, b, self_ty.clone()))
.flat_map(|b| {
GenericPredicate::from_type_bound(ctx, b, self_ty.clone())
})
.collect();
Ty::Opaque(predicates)
},
ImplTraitLoweringMode::Placeholder => {
todo!()
},
}
ImplTraitLoweringMode::Variable => {
let idx = ctx.impl_trait_counter.get();
ctx.impl_trait_counter.set(idx + 1);
let generics =
generics(ctx.db, ctx.resolver.generic_def().expect("generics in scope"));
let (self_params, list_params, impl_trait_params) = generics.provenance_split();
assert!((idx as usize) < impl_trait_params);
Ty::Bound(idx as u32 + self_params as u32 + list_params as u32)
}
ImplTraitLoweringMode::Disallowed => {
// FIXME: report error
Ty::Unknown
},
}
}
}
TypeRef::Error => Ty::Unknown,
@ -205,12 +243,31 @@ impl Ty {
let generics =
generics(ctx.db, ctx.resolver.generic_def().expect("generics in scope"));
let idx = generics.param_idx(param_id);
match ctx.type_param_mode {
TypeParamLoweringMode::Placeholder => {
// FIXME: maybe return name in resolution?
let name = generics.param_name(param_id);
Ty::Param { idx, name }
},
TypeParamLoweringMode::Variable => Ty::Bound(idx),
}
TypeNs::SelfType(impl_id) => ctx.db.impl_self_ty(impl_id).clone(),
TypeNs::AdtSelfType(adt) => ctx.db.ty(adt.into()),
}
TypeNs::SelfType(impl_id) => {
let generics = generics(ctx.db, impl_id.into());
let substs = match ctx.type_param_mode {
TypeParamLoweringMode::Placeholder => Substs::identity(&generics),
TypeParamLoweringMode::Variable => Substs::bound_vars(&generics),
};
ctx.db.impl_self_ty(impl_id).subst(&substs)
},
TypeNs::AdtSelfType(adt) => {
let generics = generics(ctx.db, adt.into());
let substs = match ctx.type_param_mode {
TypeParamLoweringMode::Placeholder => Substs::identity(&generics),
TypeParamLoweringMode::Variable => Substs::bound_vars(&generics),
};
ctx.db.ty(adt.into()).subst(&substs)
},
TypeNs::AdtId(it) => Ty::from_hir_path_inner(ctx, resolved_segment, it.into()),
TypeNs::BuiltinType(it) => Ty::from_hir_path_inner(ctx, resolved_segment, it.into()),
@ -341,7 +398,7 @@ pub(super) fn substs_from_path_segment(
// Self type as an implicit first type parameter, but it can't be
// actually provided in the type arguments
// (well, actually sometimes it can, in the form of type-relative paths: `<Foo as Default>::default()`)
// TODO handle this using type param provenance
// TODO handle this using type param provenance (if there's a self param, and not one provided, add unknown)
substs.push(Ty::Unknown);
}
if let Some(generic_args) = &segment.args_and_bindings {
@ -493,7 +550,7 @@ fn assoc_type_bindings_from_type_bound<'a>(
}
/// Build the signature of a callable item (function, struct or enum variant).
pub fn callable_item_sig(db: &impl HirDatabase, def: CallableDef) -> FnSig {
pub fn callable_item_sig(db: &impl 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),
@ -513,11 +570,7 @@ pub(crate) fn field_types_query(
VariantId::EnumVariantId(it) => it.parent.resolver(db),
};
let mut res = ArenaMap::default();
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver);
for (field_id, field_data) in var_data.fields().iter() {
res.insert(field_id, Ty::from_hir(&ctx, &field_data.type_ref))
}
@ -538,11 +591,7 @@ pub(crate) fn generic_predicates_for_param_query(
param_idx: u32,
) -> Arc<[GenericPredicate]> {
let resolver = def.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver);
resolver
.where_predicates_in_scope()
// we have to filter out all other predicates *first*, before attempting to lower them
@ -562,8 +611,7 @@ pub(crate) fn generic_predicates_for_param_recover(
impl TraitEnvironment {
pub fn lower(db: &impl HirDatabase, resolver: &Resolver) -> Arc<TraitEnvironment> {
let ctx =
TyLoweringContext { db, resolver, impl_trait_mode: ImplTraitLoweringMode::Disallowed };
let ctx = TyLoweringContext::new(db, &resolver);
let predicates = resolver
.where_predicates_in_scope()
.flat_map(|pred| GenericPredicate::from_where_predicate(&ctx, pred))
@ -579,11 +627,7 @@ pub(crate) fn generic_predicates_query(
def: GenericDefId,
) -> Arc<[GenericPredicate]> {
let resolver = def.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver);
resolver
.where_predicates_in_scope()
.flat_map(|pred| GenericPredicate::from_where_predicate(&ctx, pred))
@ -593,11 +637,7 @@ pub(crate) fn generic_predicates_query(
/// Resolve the default type params from generics
pub(crate) fn generic_defaults_query(db: &impl HirDatabase, def: GenericDefId) -> Substs {
let resolver = def.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver);
let generic_params = generics(db, def.into());
let defaults = generic_params
@ -608,56 +648,46 @@ pub(crate) fn generic_defaults_query(db: &impl HirDatabase, def: GenericDefId) -
Substs(defaults)
}
fn fn_sig_for_fn(db: &impl HirDatabase, def: FunctionId) -> FnSig {
fn fn_sig_for_fn(db: &impl HirDatabase, def: FunctionId) -> PolyFnSig {
let data = db.function_data(def);
let resolver = def.resolver(db);
let ctx_params = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Placeholder,
};
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 {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Opaque,
};
let ctx_ret = ctx_params.with_impl_trait_mode(ImplTraitLoweringMode::Opaque);
let ret = Ty::from_hir(&ctx_ret, &data.ret_type);
FnSig::from_params_and_return(params, ret)
let generics = generics(db, 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: &impl HirDatabase, def: FunctionId) -> Ty {
fn type_for_fn(db: &impl HirDatabase, def: FunctionId) -> Binders<Ty> {
let generics = generics(db, def.into());
let substs = Substs::identity(&generics);
Ty::apply(TypeCtor::FnDef(def.into()), substs)
let substs = Substs::bound_vars(&generics);
Binders::new(substs.len(), Ty::apply(TypeCtor::FnDef(def.into()), substs))
}
/// Build the declared type of a const.
fn type_for_const(db: &impl HirDatabase, def: ConstId) -> Ty {
fn type_for_const(db: &impl HirDatabase, def: ConstId) -> Binders<Ty> {
let data = db.const_data(def);
let generics = generics(db, def.into());
let resolver = def.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver)
.with_type_param_mode(TypeParamLoweringMode::Variable);
Ty::from_hir(&ctx, &data.type_ref)
Binders::new(generics.len(), Ty::from_hir(&ctx, &data.type_ref))
}
/// Build the declared type of a static.
fn type_for_static(db: &impl HirDatabase, def: StaticId) -> Ty {
fn type_for_static(db: &impl HirDatabase, def: StaticId) -> Binders<Ty> {
let data = db.static_data(def);
let resolver = def.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver);
Ty::from_hir(&ctx, &data.type_ref)
Binders::new(0, Ty::from_hir(&ctx, &data.type_ref))
}
/// Build the declared type of a static.
@ -671,79 +701,71 @@ fn type_for_builtin(def: BuiltinType) -> Ty {
})
}
fn fn_sig_for_struct_constructor(db: &impl HirDatabase, def: StructId) -> FnSig {
fn fn_sig_for_struct_constructor(db: &impl HirDatabase, def: StructId) -> PolyFnSig {
let struct_data = db.struct_data(def.into());
let fields = struct_data.variant_data.fields();
let resolver = def.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
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());
FnSig::from_params_and_return(params, ret)
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: &impl HirDatabase, def: StructId) -> Ty {
fn type_for_struct_constructor(db: &impl HirDatabase, def: StructId) -> Binders<Ty> {
let struct_data = db.struct_data(def.into());
if struct_data.variant_data.is_unit() {
return type_for_adt(db, def.into()); // Unit struct
}
let generics = generics(db, def.into());
let substs = Substs::identity(&generics);
Ty::apply(TypeCtor::FnDef(def.into()), substs)
let substs = Substs::bound_vars(&generics);
Binders::new(substs.len(), Ty::apply(TypeCtor::FnDef(def.into()), substs))
}
fn fn_sig_for_enum_variant_constructor(db: &impl HirDatabase, def: EnumVariantId) -> FnSig {
fn fn_sig_for_enum_variant_constructor(db: &impl 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);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let ctx = TyLoweringContext::new(db, &resolver);
let params =
fields.iter().map(|(_, field)| Ty::from_hir(&ctx, &field.type_ref)).collect::<Vec<_>>();
let generics = generics(db, def.parent.into());
let substs = Substs::identity(&generics);
let substs = Substs::bound_vars(&generics);
let ret = type_for_adt(db, def.parent.into()).subst(&substs);
FnSig::from_params_and_return(params, ret)
let num_binders = generics.len();
Binders::new(num_binders, FnSig::from_params_and_return(params, ret))
}
/// Build the type of a tuple enum variant constructor.
fn type_for_enum_variant_constructor(db: &impl HirDatabase, def: EnumVariantId) -> Ty {
fn type_for_enum_variant_constructor(db: &impl 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 var_data.is_unit() {
return type_for_adt(db, def.parent.into()); // Unit variant
}
let generics = generics(db, def.parent.into());
let substs = Substs::identity(&generics);
Ty::apply(TypeCtor::FnDef(EnumVariantId::from(def).into()), substs)
let substs = Substs::bound_vars(&generics);
Binders::new(substs.len(), Ty::apply(TypeCtor::FnDef(EnumVariantId::from(def).into()), substs))
}
fn type_for_adt(db: &impl HirDatabase, adt: AdtId) -> Ty {
fn type_for_adt(db: &impl HirDatabase, adt: AdtId) -> Binders<Ty> {
let generics = generics(db, adt.into());
Ty::apply(TypeCtor::Adt(adt), Substs::identity(&generics))
let substs = Substs::bound_vars(&generics);
Binders::new(substs.len(), Ty::apply(TypeCtor::Adt(adt), substs))
}
fn type_for_type_alias(db: &impl HirDatabase, t: TypeAliasId) -> Ty {
fn type_for_type_alias(db: &impl HirDatabase, t: TypeAliasId) -> Binders<Ty> {
let generics = generics(db, t.into());
let resolver = t.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
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::identity(&generics);
let substs = Substs::bound_vars(&generics);
let inner = Ty::from_hir(&ctx, type_ref.as_ref().unwrap_or(&TypeRef::Error));
inner.subst(&substs)
Binders::new(substs.len(), inner)
}
#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
@ -797,19 +819,20 @@ impl_froms!(ValueTyDefId: FunctionId, StructId, EnumVariantId, ConstId, StaticId
/// `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: &impl HirDatabase, def: TyDefId) -> Ty {
pub(crate) fn ty_query(db: &impl HirDatabase, def: TyDefId) -> Binders<Ty> {
match def {
TyDefId::BuiltinType(it) => type_for_builtin(it),
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: &impl HirDatabase, _cycle: &[String], _def: &TyDefId) -> Ty {
Ty::Unknown
pub(crate) fn ty_recover(_db: &impl HirDatabase, _cycle: &[String], _def: &TyDefId) -> Binders<Ty> {
// TODO still need correct number of binders here
Binders::new(0, Ty::Unknown)
}
pub(crate) fn value_ty_query(db: &impl HirDatabase, def: ValueTyDefId) -> Ty {
pub(crate) fn value_ty_query(db: &impl HirDatabase, def: ValueTyDefId) -> Binders<Ty> {
match def {
ValueTyDefId::FunctionId(it) => type_for_fn(db, it),
ValueTyDefId::StructId(it) => type_for_struct_constructor(db, it),
@ -819,34 +842,30 @@ pub(crate) fn value_ty_query(db: &impl HirDatabase, def: ValueTyDefId) -> Ty {
}
}
pub(crate) fn impl_self_ty_query(db: &impl HirDatabase, impl_id: ImplId) -> Ty {
pub(crate) fn impl_self_ty_query(db: &impl HirDatabase, impl_id: ImplId) -> Binders<Ty> {
let impl_data = db.impl_data(impl_id);
let resolver = impl_id.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
Ty::from_hir(&ctx, &impl_data.target_type)
let generics = generics(db, 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: &impl HirDatabase,
db: &impl HirDatabase,
_cycle: &[String],
_impl_id: &ImplId,
) -> Ty {
Ty::Unknown
impl_id: &ImplId,
) -> Binders<Ty> {
let generics = generics(db, (*impl_id).into());
Binders::new(generics.len(), Ty::Unknown)
}
pub(crate) fn impl_trait_query(db: &impl HirDatabase, impl_id: ImplId) -> Option<TraitRef> {
let impl_data = db.impl_data(impl_id);
let resolver = impl_id.resolver(db);
let ctx = TyLoweringContext {
db,
resolver: &resolver,
impl_trait_mode: ImplTraitLoweringMode::Disallowed,
};
let self_ty = db.impl_self_ty(impl_id);
let generics = generics(db, impl_id.into());
let ctx = TyLoweringContext::new(db, &resolver);
let self_ty = db.impl_self_ty(impl_id).subst(&Substs::identity(&generics));
let target_trait = impl_data.target_trait.as_ref()?;
TraitRef::from_hir(&ctx, target_trait, Some(self_ty.clone()))
}

View file

@ -65,7 +65,7 @@ impl CrateImplBlocks {
}
None => {
let self_ty = db.impl_self_ty(impl_id);
if let Some(self_ty_fp) = TyFingerprint::for_impl(&self_ty) {
if let Some(self_ty_fp) = TyFingerprint::for_impl(&self_ty.value) {
res.impls.entry(self_ty_fp).or_default().push(impl_id);
}
}
@ -496,7 +496,7 @@ fn transform_receiver_ty(
AssocContainerId::ContainerId(_) => unreachable!(),
};
let sig = db.callable_item_signature(function_id.into());
Some(sig.params()[0].clone().subst(&substs))
Some(sig.value.params()[0].clone().subst_bound_vars(&substs))
}
pub fn implements_trait(

View file

@ -1220,7 +1220,7 @@ fn test() {
}
#[test]
fn infer_impl_generics() {
fn infer_impl_generics_basic() {
assert_snapshot!(
infer(r#"
struct A<T1, T2> {

View file

@ -5,7 +5,7 @@ use std::sync::Arc;
use hir_def::{
adt::VariantData,
db::DefDatabase,
generics::{GenericParams, TypeParamData},
generics::{GenericParams, TypeParamData, TypeParamProvenance},
path::Path,
resolver::{HasResolver, TypeNs},
type_ref::TypeRef,
@ -117,19 +117,31 @@ impl Generics {
pub(crate) fn len(&self) -> usize {
self.len_split().0
}
/// (total, parents, child)
pub(crate) fn len_split(&self) -> (usize, usize, usize) {
let parent = self.parent_generics.as_ref().map_or(0, |p| p.len());
let child = self.params.types.len();
(parent + child, parent, child)
}
/// (self, type param list, impl trait)
pub(crate) fn provenance_split(&self) -> (usize, usize, usize) {
let self_params = self.params.types.iter().filter(|(_, p)| p.provenance == TypeParamProvenance::TraitSelf).count();
let list_params = self.params.types.iter().filter(|(_, p)| p.provenance == TypeParamProvenance::TypeParamList).count();
let impl_trait_params = self.params.types.iter().filter(|(_, p)| p.provenance == TypeParamProvenance::ArgumentImplTrait).count();
(self_params, list_params, impl_trait_params)
}
pub(crate) fn param_idx(&self, param: TypeParamId) -> u32 {
self.find_param(param).0
}
pub(crate) fn param_name(&self, param: TypeParamId) -> Name {
// FIXME make this return Option
self.find_param(param).1.name.clone().unwrap_or_else(Name::missing)
}
fn find_param(&self, param: TypeParamId) -> (u32, &TypeParamData) {
if param.parent == self.def {
let (idx, (_local_id, data)) = self