From a87579500a2c35597071efd0ad6983927f0c1815 Mon Sep 17 00:00:00 2001 From: Aleksey Kladov Date: Wed, 27 Nov 2019 17:46:02 +0300 Subject: Move Ty --- crates/ra_hir/src/ty/infer/coerce.rs | 357 ------------------ crates/ra_hir/src/ty/infer/expr.rs | 689 ----------------------------------- crates/ra_hir/src/ty/infer/pat.rs | 189 ---------- crates/ra_hir/src/ty/infer/path.rs | 273 -------------- crates/ra_hir/src/ty/infer/unify.rs | 166 --------- 5 files changed, 1674 deletions(-) delete mode 100644 crates/ra_hir/src/ty/infer/coerce.rs delete mode 100644 crates/ra_hir/src/ty/infer/expr.rs delete mode 100644 crates/ra_hir/src/ty/infer/pat.rs delete mode 100644 crates/ra_hir/src/ty/infer/path.rs delete mode 100644 crates/ra_hir/src/ty/infer/unify.rs (limited to 'crates/ra_hir/src/ty/infer') diff --git a/crates/ra_hir/src/ty/infer/coerce.rs b/crates/ra_hir/src/ty/infer/coerce.rs deleted file mode 100644 index 3fb5d8a83..000000000 --- a/crates/ra_hir/src/ty/infer/coerce.rs +++ /dev/null @@ -1,357 +0,0 @@ -//! Coercion logic. Coercions are certain type conversions that can implicitly -//! happen in certain places, e.g. weakening `&mut` to `&` or deref coercions -//! like going from `&Vec` to `&[T]`. -//! -//! See: https://doc.rust-lang.org/nomicon/coercions.html - -use hir_def::{ - lang_item::LangItemTarget, - resolver::{HasResolver, Resolver}, - type_ref::Mutability, - AdtId, -}; -use rustc_hash::FxHashMap; -use test_utils::tested_by; - -use crate::{ - db::HirDatabase, - ty::{autoderef, Substs, TraitRef, Ty, TypeCtor, TypeWalk}, -}; - -use super::{InEnvironment, InferTy, InferenceContext, TypeVarValue}; - -impl<'a, D: HirDatabase> InferenceContext<'a, D> { - /// Unify two types, but may coerce the first one to the second one - /// using "implicit coercion rules" if needed. - pub(super) fn coerce(&mut self, from_ty: &Ty, to_ty: &Ty) -> bool { - let from_ty = self.resolve_ty_shallow(from_ty).into_owned(); - let to_ty = self.resolve_ty_shallow(to_ty); - self.coerce_inner(from_ty, &to_ty) - } - - /// Merge two types from different branches, with possible implicit coerce. - /// - /// Note that it is only possible that one type are coerced to another. - /// Coercing both types to another least upper bound type is not possible in rustc, - /// which will simply result in "incompatible types" error. - pub(super) fn coerce_merge_branch<'t>(&mut self, ty1: &Ty, ty2: &Ty) -> Ty { - if self.coerce(ty1, ty2) { - ty2.clone() - } else if self.coerce(ty2, ty1) { - ty1.clone() - } else { - tested_by!(coerce_merge_fail_fallback); - // For incompatible types, we use the latter one as result - // to be better recovery for `if` without `else`. - ty2.clone() - } - } - - pub(super) fn init_coerce_unsized_map( - db: &'a D, - resolver: &Resolver, - ) -> FxHashMap<(TypeCtor, TypeCtor), usize> { - let krate = resolver.krate().unwrap(); - let impls = match db.lang_item(krate.into(), "coerce_unsized".into()) { - Some(LangItemTarget::TraitId(trait_)) => { - db.impls_for_trait(krate.into(), trait_.into()) - } - _ => return FxHashMap::default(), - }; - - impls - .iter() - .filter_map(|&impl_id| { - let impl_data = db.impl_data(impl_id); - let resolver = impl_id.resolver(db); - let target_ty = Ty::from_hir(db, &resolver, &impl_data.target_type); - - // `CoerseUnsized` has one generic parameter for the target type. - let trait_ref = TraitRef::from_hir( - db, - &resolver, - impl_data.target_trait.as_ref()?, - Some(target_ty), - )?; - let cur_from_ty = trait_ref.substs.0.get(0)?; - let cur_to_ty = trait_ref.substs.0.get(1)?; - - match (&cur_from_ty, cur_to_ty) { - (ty_app!(ctor1, st1), ty_app!(ctor2, st2)) => { - // FIXME: We return the first non-equal bound as the type parameter to coerce to unsized type. - // This works for smart-pointer-like coercion, which covers all impls from std. - st1.iter().zip(st2.iter()).enumerate().find_map(|(i, (ty1, ty2))| { - match (ty1, ty2) { - (Ty::Param { idx: p1, .. }, Ty::Param { idx: p2, .. }) - if p1 != p2 => - { - Some(((*ctor1, *ctor2), i)) - } - _ => None, - } - }) - } - _ => None, - } - }) - .collect() - } - - fn coerce_inner(&mut self, mut from_ty: Ty, to_ty: &Ty) -> bool { - match (&from_ty, to_ty) { - // Never type will make type variable to fallback to Never Type instead of Unknown. - (ty_app!(TypeCtor::Never), Ty::Infer(InferTy::TypeVar(tv))) => { - let var = self.new_maybe_never_type_var(); - self.var_unification_table.union_value(*tv, TypeVarValue::Known(var)); - return true; - } - (ty_app!(TypeCtor::Never), _) => return true, - - // Trivial cases, this should go after `never` check to - // avoid infer result type to be never - _ => { - if self.unify_inner_trivial(&from_ty, &to_ty) { - return true; - } - } - } - - // Pointer weakening and function to pointer - match (&mut from_ty, to_ty) { - // `*mut T`, `&mut T, `&T`` -> `*const T` - // `&mut T` -> `&T` - // `&mut T` -> `*mut T` - (ty_app!(c1@TypeCtor::RawPtr(_)), ty_app!(c2@TypeCtor::RawPtr(Mutability::Shared))) - | (ty_app!(c1@TypeCtor::Ref(_)), ty_app!(c2@TypeCtor::RawPtr(Mutability::Shared))) - | (ty_app!(c1@TypeCtor::Ref(_)), ty_app!(c2@TypeCtor::Ref(Mutability::Shared))) - | (ty_app!(c1@TypeCtor::Ref(Mutability::Mut)), ty_app!(c2@TypeCtor::RawPtr(_))) => { - *c1 = *c2; - } - - // Illegal mutablity conversion - ( - ty_app!(TypeCtor::RawPtr(Mutability::Shared)), - ty_app!(TypeCtor::RawPtr(Mutability::Mut)), - ) - | ( - ty_app!(TypeCtor::Ref(Mutability::Shared)), - ty_app!(TypeCtor::Ref(Mutability::Mut)), - ) => return false, - - // `{function_type}` -> `fn()` - (ty_app!(TypeCtor::FnDef(_)), ty_app!(TypeCtor::FnPtr { .. })) => { - match from_ty.callable_sig(self.db) { - None => return false, - Some(sig) => { - let num_args = sig.params_and_return.len() as u16 - 1; - from_ty = - Ty::apply(TypeCtor::FnPtr { num_args }, Substs(sig.params_and_return)); - } - } - } - - _ => {} - } - - if let Some(ret) = self.try_coerce_unsized(&from_ty, &to_ty) { - return ret; - } - - // Auto Deref if cannot coerce - match (&from_ty, to_ty) { - // FIXME: DerefMut - (ty_app!(TypeCtor::Ref(_), st1), ty_app!(TypeCtor::Ref(_), st2)) => { - self.unify_autoderef_behind_ref(&st1[0], &st2[0]) - } - - // Otherwise, normal unify - _ => self.unify(&from_ty, to_ty), - } - } - - /// Coerce a type using `from_ty: CoerceUnsized` - /// - /// See: https://doc.rust-lang.org/nightly/std/marker/trait.CoerceUnsized.html - fn try_coerce_unsized(&mut self, from_ty: &Ty, to_ty: &Ty) -> Option { - let (ctor1, st1, ctor2, st2) = match (from_ty, to_ty) { - (ty_app!(ctor1, st1), ty_app!(ctor2, st2)) => (ctor1, st1, ctor2, st2), - _ => return None, - }; - - let coerce_generic_index = *self.coerce_unsized_map.get(&(*ctor1, *ctor2))?; - - // Check `Unsize` first - match self.check_unsize_and_coerce( - st1.0.get(coerce_generic_index)?, - st2.0.get(coerce_generic_index)?, - 0, - ) { - Some(true) => {} - ret => return ret, - } - - let ret = st1 - .iter() - .zip(st2.iter()) - .enumerate() - .filter(|&(idx, _)| idx != coerce_generic_index) - .all(|(_, (ty1, ty2))| self.unify(ty1, ty2)); - - Some(ret) - } - - /// Check if `from_ty: Unsize`, and coerce to `to_ty` if it holds. - /// - /// It should not be directly called. It is only used by `try_coerce_unsized`. - /// - /// See: https://doc.rust-lang.org/nightly/std/marker/trait.Unsize.html - fn check_unsize_and_coerce(&mut self, from_ty: &Ty, to_ty: &Ty, depth: usize) -> Option { - if depth > 1000 { - panic!("Infinite recursion in coercion"); - } - - match (&from_ty, &to_ty) { - // `[T; N]` -> `[T]` - (ty_app!(TypeCtor::Array, st1), ty_app!(TypeCtor::Slice, st2)) => { - Some(self.unify(&st1[0], &st2[0])) - } - - // `T` -> `dyn Trait` when `T: Trait` - (_, Ty::Dyn(_)) => { - // FIXME: Check predicates - Some(true) - } - - // `(..., T)` -> `(..., U)` when `T: Unsize` - ( - ty_app!(TypeCtor::Tuple { cardinality: len1 }, st1), - ty_app!(TypeCtor::Tuple { cardinality: len2 }, st2), - ) => { - if len1 != len2 || *len1 == 0 { - return None; - } - - match self.check_unsize_and_coerce( - st1.last().unwrap(), - st2.last().unwrap(), - depth + 1, - ) { - Some(true) => {} - ret => return ret, - } - - let ret = st1[..st1.len() - 1] - .iter() - .zip(&st2[..st2.len() - 1]) - .all(|(ty1, ty2)| self.unify(ty1, ty2)); - - Some(ret) - } - - // Foo<..., T, ...> is Unsize> if: - // - T: Unsize - // - Foo is a struct - // - Only the last field of Foo has a type involving T - // - T is not part of the type of any other fields - // - Bar: Unsize>, if the last field of Foo has type Bar - ( - ty_app!(TypeCtor::Adt(AdtId::StructId(struct1)), st1), - ty_app!(TypeCtor::Adt(AdtId::StructId(struct2)), st2), - ) if struct1 == struct2 => { - let field_tys = self.db.field_types((*struct1).into()); - let struct_data = self.db.struct_data(*struct1); - - let mut fields = struct_data.variant_data.fields().iter(); - let (last_field_id, _data) = fields.next_back()?; - - // Get the generic parameter involved in the last field. - let unsize_generic_index = { - let mut index = None; - let mut multiple_param = false; - field_tys[last_field_id].walk(&mut |ty| match ty { - &Ty::Param { idx, .. } => { - if index.is_none() { - index = Some(idx); - } else if Some(idx) != index { - multiple_param = true; - } - } - _ => {} - }); - - if multiple_param { - return None; - } - index? - }; - - // Check other fields do not involve it. - let mut multiple_used = false; - fields.for_each(|(field_id, _data)| { - field_tys[field_id].walk(&mut |ty| match ty { - &Ty::Param { idx, .. } if idx == unsize_generic_index => { - multiple_used = true - } - _ => {} - }) - }); - if multiple_used { - return None; - } - - let unsize_generic_index = unsize_generic_index as usize; - - // Check `Unsize` first - match self.check_unsize_and_coerce( - st1.get(unsize_generic_index)?, - st2.get(unsize_generic_index)?, - depth + 1, - ) { - Some(true) => {} - ret => return ret, - } - - // Then unify other parameters - let ret = st1 - .iter() - .zip(st2.iter()) - .enumerate() - .filter(|&(idx, _)| idx != unsize_generic_index) - .all(|(_, (ty1, ty2))| self.unify(ty1, ty2)); - - Some(ret) - } - - _ => None, - } - } - - /// Unify `from_ty` to `to_ty` with optional auto Deref - /// - /// Note that the parameters are already stripped the outer reference. - fn unify_autoderef_behind_ref(&mut self, from_ty: &Ty, to_ty: &Ty) -> bool { - let canonicalized = self.canonicalizer().canonicalize_ty(from_ty.clone()); - let to_ty = self.resolve_ty_shallow(&to_ty); - // FIXME: Auto DerefMut - for derefed_ty in autoderef::autoderef( - self.db, - self.resolver.krate(), - InEnvironment { - value: canonicalized.value.clone(), - environment: self.trait_env.clone(), - }, - ) { - let derefed_ty = canonicalized.decanonicalize_ty(derefed_ty.value); - match (&*self.resolve_ty_shallow(&derefed_ty), &*to_ty) { - // Stop when constructor matches. - (ty_app!(from_ctor, st1), ty_app!(to_ctor, st2)) if from_ctor == to_ctor => { - // It will not recurse to `coerce`. - return self.unify_substs(st1, st2, 0); - } - _ => {} - } - } - - false - } -} diff --git a/crates/ra_hir/src/ty/infer/expr.rs b/crates/ra_hir/src/ty/infer/expr.rs deleted file mode 100644 index f9ededa23..000000000 --- a/crates/ra_hir/src/ty/infer/expr.rs +++ /dev/null @@ -1,689 +0,0 @@ -//! Type inference for expressions. - -use std::iter::{repeat, repeat_with}; -use std::sync::Arc; - -use hir_def::{ - builtin_type::Signedness, - expr::{Array, BinaryOp, Expr, ExprId, Literal, Statement, UnaryOp}, - generics::GenericParams, - path::{GenericArg, GenericArgs}, - resolver::resolver_for_expr, - AdtId, ContainerId, Lookup, StructFieldId, -}; -use hir_expand::name::{self, Name}; - -use crate::{ - db::HirDatabase, - ty::{ - autoderef, method_resolution, op, traits::InEnvironment, utils::variant_data, CallableDef, - InferTy, IntTy, Mutability, Obligation, ProjectionPredicate, ProjectionTy, Substs, - TraitRef, Ty, TypeCtor, TypeWalk, Uncertain, - }, -}; - -use super::{BindingMode, Expectation, InferenceContext, InferenceDiagnostic, TypeMismatch}; - -impl<'a, D: HirDatabase> InferenceContext<'a, D> { - pub(super) fn infer_expr(&mut self, tgt_expr: ExprId, expected: &Expectation) -> Ty { - let ty = self.infer_expr_inner(tgt_expr, expected); - let could_unify = self.unify(&ty, &expected.ty); - if !could_unify { - self.result.type_mismatches.insert( - tgt_expr, - TypeMismatch { expected: expected.ty.clone(), actual: ty.clone() }, - ); - } - let ty = self.resolve_ty_as_possible(&mut vec![], ty); - ty - } - - /// Infer type of expression with possibly implicit coerce to the expected type. - /// Return the type after possible coercion. - fn infer_expr_coerce(&mut self, expr: ExprId, expected: &Expectation) -> Ty { - let ty = self.infer_expr_inner(expr, &expected); - let ty = if !self.coerce(&ty, &expected.ty) { - self.result - .type_mismatches - .insert(expr, TypeMismatch { expected: expected.ty.clone(), actual: ty.clone() }); - // Return actual type when type mismatch. - // This is needed for diagnostic when return type mismatch. - ty - } else if expected.ty == Ty::Unknown { - ty - } else { - expected.ty.clone() - }; - - self.resolve_ty_as_possible(&mut vec![], ty) - } - - fn infer_expr_inner(&mut self, tgt_expr: ExprId, expected: &Expectation) -> Ty { - let body = Arc::clone(&self.body); // avoid borrow checker problem - let ty = match &body[tgt_expr] { - Expr::Missing => Ty::Unknown, - Expr::If { condition, then_branch, else_branch } => { - // if let is desugared to match, so this is always simple if - self.infer_expr(*condition, &Expectation::has_type(Ty::simple(TypeCtor::Bool))); - - let then_ty = self.infer_expr_inner(*then_branch, &expected); - let else_ty = match else_branch { - Some(else_branch) => self.infer_expr_inner(*else_branch, &expected), - None => Ty::unit(), - }; - - self.coerce_merge_branch(&then_ty, &else_ty) - } - Expr::Block { statements, tail } => self.infer_block(statements, *tail, expected), - Expr::TryBlock { body } => { - let _inner = self.infer_expr(*body, expected); - // FIXME should be std::result::Result<{inner}, _> - Ty::Unknown - } - Expr::Loop { body } => { - self.infer_expr(*body, &Expectation::has_type(Ty::unit())); - // FIXME handle break with value - Ty::simple(TypeCtor::Never) - } - Expr::While { condition, body } => { - // while let is desugared to a match loop, so this is always simple while - self.infer_expr(*condition, &Expectation::has_type(Ty::simple(TypeCtor::Bool))); - self.infer_expr(*body, &Expectation::has_type(Ty::unit())); - Ty::unit() - } - Expr::For { iterable, body, pat } => { - let iterable_ty = self.infer_expr(*iterable, &Expectation::none()); - - let pat_ty = match self.resolve_into_iter_item() { - Some(into_iter_item_alias) => { - let pat_ty = self.new_type_var(); - let projection = ProjectionPredicate { - ty: pat_ty.clone(), - projection_ty: ProjectionTy { - associated_ty: into_iter_item_alias, - parameters: Substs::single(iterable_ty), - }, - }; - self.obligations.push(Obligation::Projection(projection)); - self.resolve_ty_as_possible(&mut vec![], pat_ty) - } - None => Ty::Unknown, - }; - - self.infer_pat(*pat, &pat_ty, BindingMode::default()); - self.infer_expr(*body, &Expectation::has_type(Ty::unit())); - Ty::unit() - } - Expr::Lambda { body, args, arg_types } => { - assert_eq!(args.len(), arg_types.len()); - - let mut sig_tys = Vec::new(); - - for (arg_pat, arg_type) in args.iter().zip(arg_types.iter()) { - let expected = if let Some(type_ref) = arg_type { - self.make_ty(type_ref) - } else { - Ty::Unknown - }; - let arg_ty = self.infer_pat(*arg_pat, &expected, BindingMode::default()); - sig_tys.push(arg_ty); - } - - // add return type - let ret_ty = self.new_type_var(); - sig_tys.push(ret_ty.clone()); - let sig_ty = Ty::apply( - TypeCtor::FnPtr { num_args: sig_tys.len() as u16 - 1 }, - Substs(sig_tys.into()), - ); - let closure_ty = Ty::apply_one( - TypeCtor::Closure { def: self.owner.into(), expr: tgt_expr }, - sig_ty, - ); - - // Eagerly try to relate the closure type with the expected - // type, otherwise we often won't have enough information to - // infer the body. - self.coerce(&closure_ty, &expected.ty); - - self.infer_expr(*body, &Expectation::has_type(ret_ty)); - closure_ty - } - Expr::Call { callee, args } => { - let callee_ty = self.infer_expr(*callee, &Expectation::none()); - let (param_tys, ret_ty) = match callee_ty.callable_sig(self.db) { - Some(sig) => (sig.params().to_vec(), sig.ret().clone()), - None => { - // Not callable - // FIXME: report an error - (Vec::new(), Ty::Unknown) - } - }; - self.register_obligations_for_call(&callee_ty); - self.check_call_arguments(args, ¶m_tys); - let ret_ty = self.normalize_associated_types_in(ret_ty); - ret_ty - } - Expr::MethodCall { receiver, args, method_name, generic_args } => self - .infer_method_call(tgt_expr, *receiver, &args, &method_name, generic_args.as_ref()), - Expr::Match { expr, arms } => { - let input_ty = self.infer_expr(*expr, &Expectation::none()); - - let mut result_ty = self.new_maybe_never_type_var(); - - for arm in arms { - for &pat in &arm.pats { - let _pat_ty = self.infer_pat(pat, &input_ty, BindingMode::default()); - } - if let Some(guard_expr) = arm.guard { - self.infer_expr( - guard_expr, - &Expectation::has_type(Ty::simple(TypeCtor::Bool)), - ); - } - - let arm_ty = self.infer_expr_inner(arm.expr, &expected); - result_ty = self.coerce_merge_branch(&result_ty, &arm_ty); - } - - result_ty - } - Expr::Path(p) => { - // FIXME this could be more efficient... - let resolver = resolver_for_expr(self.db, self.owner.into(), tgt_expr); - self.infer_path(&resolver, p, tgt_expr.into()).unwrap_or(Ty::Unknown) - } - Expr::Continue => Ty::simple(TypeCtor::Never), - Expr::Break { expr } => { - if let Some(expr) = expr { - // FIXME handle break with value - self.infer_expr(*expr, &Expectation::none()); - } - Ty::simple(TypeCtor::Never) - } - Expr::Return { expr } => { - if let Some(expr) = expr { - self.infer_expr(*expr, &Expectation::has_type(self.return_ty.clone())); - } - Ty::simple(TypeCtor::Never) - } - Expr::RecordLit { path, fields, spread } => { - let (ty, def_id) = self.resolve_variant(path.as_ref()); - if let Some(variant) = def_id { - self.write_variant_resolution(tgt_expr.into(), variant); - } - - self.unify(&ty, &expected.ty); - - let substs = ty.substs().unwrap_or_else(Substs::empty); - let field_types = - def_id.map(|it| self.db.field_types(it.into())).unwrap_or_default(); - let variant_data = def_id.map(|it| variant_data(self.db, it)); - for (field_idx, field) in fields.iter().enumerate() { - let field_def = - variant_data.as_ref().and_then(|it| match it.field(&field.name) { - Some(local_id) => { - Some(StructFieldId { parent: def_id.unwrap(), local_id }) - } - None => { - self.push_diagnostic(InferenceDiagnostic::NoSuchField { - expr: tgt_expr, - field: field_idx, - }); - None - } - }); - if let Some(field_def) = field_def { - self.result.record_field_resolutions.insert(field.expr, field_def); - } - let field_ty = field_def - .map_or(Ty::Unknown, |it| field_types[it.local_id].clone()) - .subst(&substs); - self.infer_expr_coerce(field.expr, &Expectation::has_type(field_ty)); - } - if let Some(expr) = spread { - self.infer_expr(*expr, &Expectation::has_type(ty.clone())); - } - ty - } - Expr::Field { expr, name } => { - let receiver_ty = self.infer_expr(*expr, &Expectation::none()); - let canonicalized = self.canonicalizer().canonicalize_ty(receiver_ty); - let ty = autoderef::autoderef( - self.db, - self.resolver.krate(), - InEnvironment { - value: canonicalized.value.clone(), - environment: self.trait_env.clone(), - }, - ) - .find_map(|derefed_ty| match canonicalized.decanonicalize_ty(derefed_ty.value) { - Ty::Apply(a_ty) => match a_ty.ctor { - TypeCtor::Tuple { .. } => name - .as_tuple_index() - .and_then(|idx| a_ty.parameters.0.get(idx).cloned()), - TypeCtor::Adt(AdtId::StructId(s)) => { - self.db.struct_data(s).variant_data.field(name).map(|local_id| { - let field = StructFieldId { parent: s.into(), local_id }.into(); - self.write_field_resolution(tgt_expr, field); - self.db.field_types(s.into())[field.local_id] - .clone() - .subst(&a_ty.parameters) - }) - } - // FIXME: - TypeCtor::Adt(AdtId::UnionId(_)) => None, - _ => None, - }, - _ => None, - }) - .unwrap_or(Ty::Unknown); - let ty = self.insert_type_vars(ty); - self.normalize_associated_types_in(ty) - } - Expr::Await { expr } => { - let inner_ty = self.infer_expr(*expr, &Expectation::none()); - let ty = match self.resolve_future_future_output() { - Some(future_future_output_alias) => { - let ty = self.new_type_var(); - let projection = ProjectionPredicate { - ty: ty.clone(), - projection_ty: ProjectionTy { - associated_ty: future_future_output_alias, - parameters: Substs::single(inner_ty), - }, - }; - self.obligations.push(Obligation::Projection(projection)); - self.resolve_ty_as_possible(&mut vec![], ty) - } - None => Ty::Unknown, - }; - ty - } - Expr::Try { expr } => { - let inner_ty = self.infer_expr(*expr, &Expectation::none()); - let ty = match self.resolve_ops_try_ok() { - Some(ops_try_ok_alias) => { - let ty = self.new_type_var(); - let projection = ProjectionPredicate { - ty: ty.clone(), - projection_ty: ProjectionTy { - associated_ty: ops_try_ok_alias, - parameters: Substs::single(inner_ty), - }, - }; - self.obligations.push(Obligation::Projection(projection)); - self.resolve_ty_as_possible(&mut vec![], ty) - } - None => Ty::Unknown, - }; - ty - } - Expr::Cast { expr, type_ref } => { - let _inner_ty = self.infer_expr(*expr, &Expectation::none()); - let cast_ty = self.make_ty(type_ref); - // FIXME check the cast... - cast_ty - } - Expr::Ref { expr, mutability } => { - let expectation = - if let Some((exp_inner, exp_mutability)) = &expected.ty.as_reference() { - if *exp_mutability == Mutability::Mut && *mutability == Mutability::Shared { - // FIXME: throw type error - expected mut reference but found shared ref, - // which cannot be coerced - } - Expectation::has_type(Ty::clone(exp_inner)) - } else { - Expectation::none() - }; - // FIXME reference coercions etc. - let inner_ty = self.infer_expr(*expr, &expectation); - Ty::apply_one(TypeCtor::Ref(*mutability), inner_ty) - } - Expr::Box { expr } => { - let inner_ty = self.infer_expr(*expr, &Expectation::none()); - if let Some(box_) = self.resolve_boxed_box() { - Ty::apply_one(TypeCtor::Adt(box_), inner_ty) - } else { - Ty::Unknown - } - } - Expr::UnaryOp { expr, op } => { - let inner_ty = self.infer_expr(*expr, &Expectation::none()); - match op { - UnaryOp::Deref => match self.resolver.krate() { - Some(krate) => { - let canonicalized = self.canonicalizer().canonicalize_ty(inner_ty); - match autoderef::deref( - self.db, - krate, - InEnvironment { - value: &canonicalized.value, - environment: self.trait_env.clone(), - }, - ) { - Some(derefed_ty) => { - canonicalized.decanonicalize_ty(derefed_ty.value) - } - None => Ty::Unknown, - } - } - None => Ty::Unknown, - }, - UnaryOp::Neg => { - match &inner_ty { - Ty::Apply(a_ty) => match a_ty.ctor { - TypeCtor::Int(Uncertain::Unknown) - | TypeCtor::Int(Uncertain::Known(IntTy { - signedness: Signedness::Signed, - .. - })) - | TypeCtor::Float(..) => inner_ty, - _ => Ty::Unknown, - }, - Ty::Infer(InferTy::IntVar(..)) | Ty::Infer(InferTy::FloatVar(..)) => { - inner_ty - } - // FIXME: resolve ops::Neg trait - _ => Ty::Unknown, - } - } - UnaryOp::Not => { - match &inner_ty { - Ty::Apply(a_ty) => match a_ty.ctor { - TypeCtor::Bool | TypeCtor::Int(_) => inner_ty, - _ => Ty::Unknown, - }, - Ty::Infer(InferTy::IntVar(..)) => inner_ty, - // FIXME: resolve ops::Not trait for inner_ty - _ => Ty::Unknown, - } - } - } - } - Expr::BinaryOp { lhs, rhs, op } => match op { - Some(op) => { - let lhs_expectation = match op { - BinaryOp::LogicOp(..) => Expectation::has_type(Ty::simple(TypeCtor::Bool)), - _ => Expectation::none(), - }; - let lhs_ty = self.infer_expr(*lhs, &lhs_expectation); - // FIXME: find implementation of trait corresponding to operation - // symbol and resolve associated `Output` type - let rhs_expectation = op::binary_op_rhs_expectation(*op, lhs_ty); - let rhs_ty = self.infer_expr(*rhs, &Expectation::has_type(rhs_expectation)); - - // FIXME: similar as above, return ty is often associated trait type - op::binary_op_return_ty(*op, rhs_ty) - } - _ => Ty::Unknown, - }, - Expr::Index { base, index } => { - let _base_ty = self.infer_expr(*base, &Expectation::none()); - let _index_ty = self.infer_expr(*index, &Expectation::none()); - // FIXME: use `std::ops::Index::Output` to figure out the real return type - Ty::Unknown - } - Expr::Tuple { exprs } => { - let mut tys = match &expected.ty { - ty_app!(TypeCtor::Tuple { .. }, st) => st - .iter() - .cloned() - .chain(repeat_with(|| self.new_type_var())) - .take(exprs.len()) - .collect::>(), - _ => (0..exprs.len()).map(|_| self.new_type_var()).collect(), - }; - - for (expr, ty) in exprs.iter().zip(tys.iter_mut()) { - self.infer_expr_coerce(*expr, &Expectation::has_type(ty.clone())); - } - - Ty::apply(TypeCtor::Tuple { cardinality: tys.len() as u16 }, Substs(tys.into())) - } - Expr::Array(array) => { - let elem_ty = match &expected.ty { - ty_app!(TypeCtor::Array, st) | ty_app!(TypeCtor::Slice, st) => { - st.as_single().clone() - } - _ => self.new_type_var(), - }; - - match array { - Array::ElementList(items) => { - for expr in items.iter() { - self.infer_expr_coerce(*expr, &Expectation::has_type(elem_ty.clone())); - } - } - Array::Repeat { initializer, repeat } => { - self.infer_expr_coerce( - *initializer, - &Expectation::has_type(elem_ty.clone()), - ); - self.infer_expr( - *repeat, - &Expectation::has_type(Ty::simple(TypeCtor::Int(Uncertain::Known( - IntTy::usize(), - )))), - ); - } - } - - Ty::apply_one(TypeCtor::Array, elem_ty) - } - Expr::Literal(lit) => match lit { - Literal::Bool(..) => Ty::simple(TypeCtor::Bool), - Literal::String(..) => { - Ty::apply_one(TypeCtor::Ref(Mutability::Shared), Ty::simple(TypeCtor::Str)) - } - Literal::ByteString(..) => { - let byte_type = Ty::simple(TypeCtor::Int(Uncertain::Known(IntTy::u8()))); - let slice_type = Ty::apply_one(TypeCtor::Slice, byte_type); - Ty::apply_one(TypeCtor::Ref(Mutability::Shared), slice_type) - } - Literal::Char(..) => Ty::simple(TypeCtor::Char), - Literal::Int(_v, ty) => Ty::simple(TypeCtor::Int((*ty).into())), - Literal::Float(_v, ty) => Ty::simple(TypeCtor::Float((*ty).into())), - }, - }; - // use a new type variable if we got Ty::Unknown here - let ty = self.insert_type_vars_shallow(ty); - let ty = self.resolve_ty_as_possible(&mut vec![], ty); - self.write_expr_ty(tgt_expr, ty.clone()); - ty - } - - fn infer_block( - &mut self, - statements: &[Statement], - tail: Option, - expected: &Expectation, - ) -> Ty { - let mut diverges = false; - for stmt in statements { - match stmt { - Statement::Let { pat, type_ref, initializer } => { - let decl_ty = - type_ref.as_ref().map(|tr| self.make_ty(tr)).unwrap_or(Ty::Unknown); - - // Always use the declared type when specified - let mut ty = decl_ty.clone(); - - if let Some(expr) = initializer { - let actual_ty = - self.infer_expr_coerce(*expr, &Expectation::has_type(decl_ty.clone())); - if decl_ty == Ty::Unknown { - ty = actual_ty; - } - } - - let ty = self.resolve_ty_as_possible(&mut vec![], ty); - self.infer_pat(*pat, &ty, BindingMode::default()); - } - Statement::Expr(expr) => { - if let ty_app!(TypeCtor::Never) = self.infer_expr(*expr, &Expectation::none()) { - diverges = true; - } - } - } - } - - let ty = if let Some(expr) = tail { - self.infer_expr_coerce(expr, expected) - } else { - self.coerce(&Ty::unit(), &expected.ty); - Ty::unit() - }; - if diverges { - Ty::simple(TypeCtor::Never) - } else { - ty - } - } - - fn infer_method_call( - &mut self, - tgt_expr: ExprId, - receiver: ExprId, - args: &[ExprId], - method_name: &Name, - generic_args: Option<&GenericArgs>, - ) -> Ty { - let receiver_ty = self.infer_expr(receiver, &Expectation::none()); - let canonicalized_receiver = self.canonicalizer().canonicalize_ty(receiver_ty.clone()); - let resolved = method_resolution::lookup_method( - &canonicalized_receiver.value, - self.db, - method_name, - &self.resolver, - ); - let (derefed_receiver_ty, method_ty, def_generics) = match resolved { - Some((ty, func)) => { - let ty = canonicalized_receiver.decanonicalize_ty(ty); - self.write_method_resolution(tgt_expr, func); - (ty, self.db.value_ty(func.into()), Some(self.db.generic_params(func.into()))) - } - None => (receiver_ty, 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 = 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) { - Some(sig) => { - if !sig.params().is_empty() { - (sig.params()[0].clone(), sig.params()[1..].to_vec(), sig.ret().clone()) - } else { - (Ty::Unknown, Vec::new(), sig.ret().clone()) - } - } - None => (Ty::Unknown, Vec::new(), Ty::Unknown), - }; - // Apply autoref so the below unification works correctly - // FIXME: return correct autorefs from lookup_method - let actual_receiver_ty = match expected_receiver_ty.as_reference() { - Some((_, mutability)) => Ty::apply_one(TypeCtor::Ref(mutability), derefed_receiver_ty), - _ => derefed_receiver_ty, - }; - self.unify(&expected_receiver_ty, &actual_receiver_ty); - - self.check_call_arguments(args, ¶m_tys); - let ret_ty = self.normalize_associated_types_in(ret_ty); - ret_ty - } - - fn check_call_arguments(&mut self, args: &[ExprId], param_tys: &[Ty]) { - // Quoting https://github.com/rust-lang/rust/blob/6ef275e6c3cb1384ec78128eceeb4963ff788dca/src/librustc_typeck/check/mod.rs#L3325 -- - // We do this in a pretty awful way: first we type-check any arguments - // that are not closures, then we type-check the closures. This is so - // that we have more information about the types of arguments when we - // type-check the functions. This isn't really the right way to do this. - for &check_closures in &[false, true] { - let param_iter = param_tys.iter().cloned().chain(repeat(Ty::Unknown)); - for (&arg, param_ty) in args.iter().zip(param_iter) { - let is_closure = match &self.body[arg] { - Expr::Lambda { .. } => true, - _ => false, - }; - - if is_closure != check_closures { - continue; - } - - let param_ty = self.normalize_associated_types_in(param_ty); - self.infer_expr_coerce(arg, &Expectation::has_type(param_ty.clone())); - } - } - } - - fn substs_for_method_call( - &mut self, - def_generics: Option>, - generic_args: Option<&GenericArgs>, - receiver_ty: &Ty, - ) -> Substs { - let (parent_param_count, param_count) = - def_generics.as_ref().map_or((0, 0), |g| (g.count_parent_params(), g.params.len())); - let mut substs = Vec::with_capacity(parent_param_count + param_count); - // Parent arguments are unknown, except for the receiver type - if let Some(parent_generics) = def_generics.and_then(|p| p.parent_params.clone()) { - for param in &parent_generics.params { - if param.name == name::SELF_TYPE { - substs.push(receiver_ty.clone()); - } else { - substs.push(Ty::Unknown); - } - } - } - // handle provided type arguments - if let Some(generic_args) = generic_args { - // if args are provided, it should be all of them, but we can't rely on that - for arg in generic_args.args.iter().take(param_count) { - match arg { - GenericArg::Type(type_ref) => { - let ty = self.make_ty(type_ref); - substs.push(ty); - } - } - } - }; - let supplied_params = substs.len(); - for _ in supplied_params..parent_param_count + param_count { - substs.push(Ty::Unknown); - } - assert_eq!(substs.len(), parent_param_count + param_count); - Substs(substs.into()) - } - - fn register_obligations_for_call(&mut self, callable_ty: &Ty) { - if let Ty::Apply(a_ty) = callable_ty { - if let TypeCtor::FnDef(def) = a_ty.ctor { - let generic_predicates = self.db.generic_predicates(def.into()); - for predicate in generic_predicates.iter() { - let predicate = predicate.clone().subst(&a_ty.parameters); - if let Some(obligation) = Obligation::from_predicate(predicate) { - self.obligations.push(obligation); - } - } - // add obligation for trait implementation, if this is a trait method - match def { - CallableDef::FunctionId(f) => { - if let ContainerId::TraitId(trait_) = f.lookup(self.db).container { - // construct a TraitDef - let substs = a_ty.parameters.prefix( - self.db - .generic_params(trait_.into()) - .count_params_including_parent(), - ); - self.obligations.push(Obligation::Trait(TraitRef { - trait_: trait_.into(), - substs, - })); - } - } - CallableDef::StructId(_) | CallableDef::EnumVariantId(_) => {} - } - } - } - } -} diff --git a/crates/ra_hir/src/ty/infer/pat.rs b/crates/ra_hir/src/ty/infer/pat.rs deleted file mode 100644 index a14774607..000000000 --- a/crates/ra_hir/src/ty/infer/pat.rs +++ /dev/null @@ -1,189 +0,0 @@ -//! Type inference for patterns. - -use std::iter::repeat; -use std::sync::Arc; - -use hir_def::{ - expr::{BindingAnnotation, Pat, PatId, RecordFieldPat}, - path::Path, - type_ref::Mutability, -}; -use hir_expand::name::Name; -use test_utils::tested_by; - -use super::{BindingMode, InferenceContext}; -use crate::{ - db::HirDatabase, - ty::{utils::variant_data, Substs, Ty, TypeCtor, TypeWalk}, -}; - -impl<'a, D: HirDatabase> InferenceContext<'a, D> { - fn infer_tuple_struct_pat( - &mut self, - path: Option<&Path>, - subpats: &[PatId], - expected: &Ty, - default_bm: BindingMode, - ) -> Ty { - let (ty, def) = self.resolve_variant(path); - let var_data = def.map(|it| variant_data(self.db, it)); - self.unify(&ty, expected); - - let substs = ty.substs().unwrap_or_else(Substs::empty); - - let field_tys = def.map(|it| self.db.field_types(it.into())).unwrap_or_default(); - - for (i, &subpat) in subpats.iter().enumerate() { - let expected_ty = var_data - .as_ref() - .and_then(|d| d.field(&Name::new_tuple_field(i))) - .map_or(Ty::Unknown, |field| field_tys[field].clone()) - .subst(&substs); - let expected_ty = self.normalize_associated_types_in(expected_ty); - self.infer_pat(subpat, &expected_ty, default_bm); - } - - ty - } - - fn infer_record_pat( - &mut self, - path: Option<&Path>, - subpats: &[RecordFieldPat], - expected: &Ty, - default_bm: BindingMode, - id: PatId, - ) -> Ty { - let (ty, def) = self.resolve_variant(path); - let var_data = def.map(|it| variant_data(self.db, it)); - if let Some(variant) = def { - self.write_variant_resolution(id.into(), variant); - } - - self.unify(&ty, expected); - - let substs = ty.substs().unwrap_or_else(Substs::empty); - - let field_tys = def.map(|it| self.db.field_types(it.into())).unwrap_or_default(); - for subpat in subpats { - let matching_field = var_data.as_ref().and_then(|it| it.field(&subpat.name)); - let expected_ty = - matching_field.map_or(Ty::Unknown, |field| field_tys[field].clone()).subst(&substs); - let expected_ty = self.normalize_associated_types_in(expected_ty); - self.infer_pat(subpat.pat, &expected_ty, default_bm); - } - - ty - } - - pub(super) fn infer_pat( - &mut self, - pat: PatId, - mut expected: &Ty, - mut default_bm: BindingMode, - ) -> Ty { - let body = Arc::clone(&self.body); // avoid borrow checker problem - - let is_non_ref_pat = match &body[pat] { - Pat::Tuple(..) - | Pat::TupleStruct { .. } - | Pat::Record { .. } - | Pat::Range { .. } - | Pat::Slice { .. } => true, - // FIXME: Path/Lit might actually evaluate to ref, but inference is unimplemented. - Pat::Path(..) | Pat::Lit(..) => true, - Pat::Wild | Pat::Bind { .. } | Pat::Ref { .. } | Pat::Missing => false, - }; - if is_non_ref_pat { - while let Some((inner, mutability)) = expected.as_reference() { - expected = inner; - default_bm = match default_bm { - BindingMode::Move => BindingMode::Ref(mutability), - BindingMode::Ref(Mutability::Shared) => BindingMode::Ref(Mutability::Shared), - BindingMode::Ref(Mutability::Mut) => BindingMode::Ref(mutability), - } - } - } else if let Pat::Ref { .. } = &body[pat] { - tested_by!(match_ergonomics_ref); - // When you encounter a `&pat` pattern, reset to Move. - // This is so that `w` is by value: `let (_, &w) = &(1, &2);` - default_bm = BindingMode::Move; - } - - // Lose mutability. - let default_bm = default_bm; - let expected = expected; - - let ty = match &body[pat] { - Pat::Tuple(ref args) => { - let expectations = match expected.as_tuple() { - Some(parameters) => &*parameters.0, - _ => &[], - }; - let expectations_iter = expectations.iter().chain(repeat(&Ty::Unknown)); - - let inner_tys = args - .iter() - .zip(expectations_iter) - .map(|(&pat, ty)| self.infer_pat(pat, ty, default_bm)) - .collect(); - - Ty::apply(TypeCtor::Tuple { cardinality: args.len() as u16 }, Substs(inner_tys)) - } - Pat::Ref { pat, mutability } => { - let expectation = match expected.as_reference() { - Some((inner_ty, exp_mut)) => { - if *mutability != exp_mut { - // FIXME: emit type error? - } - inner_ty - } - _ => &Ty::Unknown, - }; - let subty = self.infer_pat(*pat, expectation, default_bm); - Ty::apply_one(TypeCtor::Ref(*mutability), subty) - } - Pat::TupleStruct { path: p, args: subpats } => { - self.infer_tuple_struct_pat(p.as_ref(), subpats, expected, default_bm) - } - Pat::Record { path: p, args: fields } => { - self.infer_record_pat(p.as_ref(), fields, expected, default_bm, pat) - } - Pat::Path(path) => { - // FIXME use correct resolver for the surrounding expression - let resolver = self.resolver.clone(); - self.infer_path(&resolver, &path, pat.into()).unwrap_or(Ty::Unknown) - } - Pat::Bind { mode, name: _, subpat } => { - let mode = if mode == &BindingAnnotation::Unannotated { - default_bm - } else { - BindingMode::convert(*mode) - }; - let inner_ty = if let Some(subpat) = subpat { - self.infer_pat(*subpat, expected, default_bm) - } else { - expected.clone() - }; - let inner_ty = self.insert_type_vars_shallow(inner_ty); - - let bound_ty = match mode { - BindingMode::Ref(mutability) => { - Ty::apply_one(TypeCtor::Ref(mutability), inner_ty.clone()) - } - BindingMode::Move => inner_ty.clone(), - }; - let bound_ty = self.resolve_ty_as_possible(&mut vec![], bound_ty); - self.write_pat_ty(pat, bound_ty); - return inner_ty; - } - _ => Ty::Unknown, - }; - // use a new type variable if we got Ty::Unknown here - let ty = self.insert_type_vars_shallow(ty); - self.unify(&ty, expected); - let ty = self.resolve_ty_as_possible(&mut vec![], ty); - self.write_pat_ty(pat, ty.clone()); - ty - } -} diff --git a/crates/ra_hir/src/ty/infer/path.rs b/crates/ra_hir/src/ty/infer/path.rs deleted file mode 100644 index 09ff79728..000000000 --- a/crates/ra_hir/src/ty/infer/path.rs +++ /dev/null @@ -1,273 +0,0 @@ -//! Path expression resolution. - -use hir_def::{ - path::{Path, PathSegment}, - resolver::{HasResolver, ResolveValueResult, Resolver, TypeNs, ValueNs}, - AssocItemId, ContainerId, Lookup, -}; -use hir_expand::name::Name; - -use crate::{ - db::HirDatabase, - ty::{method_resolution, Substs, Ty, TypeWalk, ValueTyDefId}, -}; - -use super::{ExprOrPatId, InferenceContext, TraitRef}; - -impl<'a, D: HirDatabase> InferenceContext<'a, D> { - pub(super) fn infer_path( - &mut self, - resolver: &Resolver, - path: &Path, - id: ExprOrPatId, - ) -> Option { - let ty = self.resolve_value_path(resolver, path, id)?; - let ty = self.insert_type_vars(ty); - let ty = self.normalize_associated_types_in(ty); - Some(ty) - } - - fn resolve_value_path( - &mut self, - resolver: &Resolver, - path: &Path, - id: ExprOrPatId, - ) -> Option { - let (value, self_subst) = if let crate::PathKind::Type(type_ref) = &path.kind { - if path.segments.is_empty() { - // This can't actually happen syntax-wise - return None; - } - let ty = self.make_ty(type_ref); - let remaining_segments_for_ty = &path.segments[..path.segments.len() - 1]; - let ty = Ty::from_type_relative_path(self.db, resolver, ty, remaining_segments_for_ty); - self.resolve_ty_assoc_item( - ty, - &path.segments.last().expect("path had at least one segment").name, - id, - )? - } else { - let value_or_partial = resolver.resolve_path_in_value_ns(self.db, &path)?; - - match value_or_partial { - ResolveValueResult::ValueNs(it) => (it, None), - ResolveValueResult::Partial(def, remaining_index) => { - self.resolve_assoc_item(def, path, remaining_index, id)? - } - } - }; - - let typable: ValueTyDefId = match value { - ValueNs::LocalBinding(pat) => { - let ty = self.result.type_of_pat.get(pat)?.clone(); - let ty = self.resolve_ty_as_possible(&mut vec![], ty); - return Some(ty); - } - ValueNs::FunctionId(it) => it.into(), - ValueNs::ConstId(it) => it.into(), - ValueNs::StaticId(it) => it.into(), - ValueNs::StructId(it) => it.into(), - 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 substs = Ty::substs_from_path(self.db, &self.resolver, path, typable); - let ty = ty.subst(&substs); - Some(ty) - } - - fn resolve_assoc_item( - &mut self, - def: TypeNs, - path: &Path, - remaining_index: usize, - id: ExprOrPatId, - ) -> Option<(ValueNs, Option)> { - assert!(remaining_index < path.segments.len()); - // there may be more intermediate segments between the resolved one and - // the end. Only the last segment needs to be resolved to a value; from - // the segments before that, we need to get either a type or a trait ref. - - let resolved_segment = &path.segments[remaining_index - 1]; - let remaining_segments = &path.segments[remaining_index..]; - let is_before_last = remaining_segments.len() == 1; - - match (def, is_before_last) { - (TypeNs::TraitId(trait_), true) => { - let segment = - remaining_segments.last().expect("there should be at least one segment here"); - let trait_ref = TraitRef::from_resolved_path( - self.db, - &self.resolver, - trait_.into(), - resolved_segment, - None, - ); - self.resolve_trait_assoc_item(trait_ref, segment, id) - } - (def, _) => { - // Either we already have a type (e.g. `Vec::new`), or we have a - // trait but it's not the last segment, so the next segment - // should resolve to an associated type of that trait (e.g. `::Item::default`) - let remaining_segments_for_ty = &remaining_segments[..remaining_segments.len() - 1]; - let ty = Ty::from_partly_resolved_hir_path( - self.db, - &self.resolver, - def, - resolved_segment, - remaining_segments_for_ty, - ); - if let Ty::Unknown = ty { - return None; - } - - let ty = self.insert_type_vars(ty); - let ty = self.normalize_associated_types_in(ty); - - let segment = - remaining_segments.last().expect("there should be at least one segment here"); - - self.resolve_ty_assoc_item(ty, &segment.name, id) - } - } - } - - fn resolve_trait_assoc_item( - &mut self, - trait_ref: TraitRef, - segment: &PathSegment, - id: ExprOrPatId, - ) -> Option<(ValueNs, Option)> { - let trait_ = trait_ref.trait_; - let item = self - .db - .trait_data(trait_) - .items - .iter() - .map(|(_name, id)| (*id).into()) - .find_map(|item| match item { - AssocItemId::FunctionId(func) => { - if segment.name == self.db.function_data(func).name { - Some(AssocItemId::FunctionId(func)) - } else { - None - } - } - - AssocItemId::ConstId(konst) => { - if self.db.const_data(konst).name.as_ref().map_or(false, |n| n == &segment.name) - { - Some(AssocItemId::ConstId(konst)) - } else { - None - } - } - AssocItemId::TypeAliasId(_) => None, - })?; - let def = match item { - AssocItemId::FunctionId(f) => ValueNs::FunctionId(f), - AssocItemId::ConstId(c) => ValueNs::ConstId(c), - AssocItemId::TypeAliasId(_) => unreachable!(), - }; - let substs = Substs::build_for_def(self.db, item) - .use_parent_substs(&trait_ref.substs) - .fill_with_params() - .build(); - - self.write_assoc_resolution(id, item); - Some((def, Some(substs))) - } - - fn resolve_ty_assoc_item( - &mut self, - ty: Ty, - name: &Name, - id: ExprOrPatId, - ) -> Option<(ValueNs, Option)> { - if let Ty::Unknown = ty { - return None; - } - - let canonical_ty = self.canonicalizer().canonicalize_ty(ty.clone()); - - method_resolution::iterate_method_candidates( - &canonical_ty.value, - self.db, - &self.resolver.clone(), - Some(name), - method_resolution::LookupMode::Path, - move |_ty, item| { - let (def, container) = match item { - AssocItemId::FunctionId(f) => { - (ValueNs::FunctionId(f), f.lookup(self.db).container) - } - AssocItemId::ConstId(c) => (ValueNs::ConstId(c), c.lookup(self.db).container), - AssocItemId::TypeAliasId(_) => unreachable!(), - }; - let substs = match container { - ContainerId::ImplId(_) => self.find_self_types(&def, ty.clone()), - ContainerId::TraitId(trait_) => { - // we're picking this method - let trait_substs = Substs::build_for_def(self.db, trait_) - .push(ty.clone()) - .fill(std::iter::repeat_with(|| self.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, - })); - Some(substs) - } - ContainerId::ModuleId(_) => None, - }; - - self.write_assoc_resolution(id, item.into()); - Some((def, substs)) - }, - ) - } - - fn find_self_types(&self, def: &ValueNs, actual_def_ty: Ty) -> Option { - if let ValueNs::FunctionId(func) = *def { - // We only do the infer if parent has generic params - let gen = self.db.generic_params(func.into()); - if gen.count_parent_params() == 0 { - return None; - } - - let impl_id = match func.lookup(self.db).container { - ContainerId::ImplId(it) => it, - _ => return None, - }; - let resolver = impl_id.resolver(self.db); - let impl_data = self.db.impl_data(impl_id); - let impl_block = Ty::from_hir(self.db, &resolver, &impl_data.target_type); - let impl_block_substs = impl_block.substs()?; - let actual_substs = actual_def_ty.substs()?; - - let mut new_substs = vec![Ty::Unknown; gen.count_parent_params()]; - - // The following code *link up* the function actual parma type - // and impl_block type param index - impl_block_substs.iter().zip(actual_substs.iter()).for_each(|(param, pty)| { - if let Ty::Param { idx, .. } = param { - if let Some(s) = new_substs.get_mut(*idx as usize) { - *s = pty.clone(); - } - } - }); - - Some(Substs(new_substs.into())) - } else { - None - } - } -} diff --git a/crates/ra_hir/src/ty/infer/unify.rs b/crates/ra_hir/src/ty/infer/unify.rs deleted file mode 100644 index e27bb2f82..000000000 --- a/crates/ra_hir/src/ty/infer/unify.rs +++ /dev/null @@ -1,166 +0,0 @@ -//! Unification and canonicalization logic. - -use super::{InferenceContext, Obligation}; -use crate::{ - db::HirDatabase, - ty::{ - Canonical, InEnvironment, InferTy, ProjectionPredicate, ProjectionTy, Substs, TraitRef, Ty, - TypeWalk, - }, - util::make_mut_slice, -}; - -impl<'a, D: HirDatabase> InferenceContext<'a, D> { - pub(super) fn canonicalizer<'b>(&'b mut self) -> Canonicalizer<'a, 'b, D> - where - 'a: 'b, - { - Canonicalizer { ctx: self, free_vars: Vec::new(), var_stack: Vec::new() } - } -} - -pub(super) struct Canonicalizer<'a, 'b, D: HirDatabase> -where - 'a: 'b, -{ - ctx: &'b mut InferenceContext<'a, D>, - free_vars: Vec, - /// A stack of type variables that is used to detect recursive types (which - /// are an error, but we need to protect against them to avoid stack - /// overflows). - var_stack: Vec, -} - -pub(super) struct Canonicalized { - pub value: Canonical, - free_vars: Vec, -} - -impl<'a, 'b, D: HirDatabase> Canonicalizer<'a, 'b, D> -where - 'a: 'b, -{ - fn add(&mut self, free_var: InferTy) -> usize { - self.free_vars.iter().position(|&v| v == free_var).unwrap_or_else(|| { - let next_index = self.free_vars.len(); - self.free_vars.push(free_var); - next_index - }) - } - - fn do_canonicalize_ty(&mut self, ty: Ty) -> Ty { - ty.fold(&mut |ty| match ty { - Ty::Infer(tv) => { - let inner = tv.to_inner(); - if self.var_stack.contains(&inner) { - // recursive type - return tv.fallback_value(); - } - if let Some(known_ty) = - self.ctx.var_unification_table.inlined_probe_value(inner).known() - { - self.var_stack.push(inner); - let result = self.do_canonicalize_ty(known_ty.clone()); - self.var_stack.pop(); - result - } else { - let root = self.ctx.var_unification_table.find(inner); - let free_var = match tv { - InferTy::TypeVar(_) => InferTy::TypeVar(root), - InferTy::IntVar(_) => InferTy::IntVar(root), - InferTy::FloatVar(_) => InferTy::FloatVar(root), - InferTy::MaybeNeverTypeVar(_) => InferTy::MaybeNeverTypeVar(root), - }; - let position = self.add(free_var); - Ty::Bound(position as u32) - } - } - _ => ty, - }) - } - - fn do_canonicalize_trait_ref(&mut self, mut trait_ref: TraitRef) -> TraitRef { - for ty in make_mut_slice(&mut trait_ref.substs.0) { - *ty = self.do_canonicalize_ty(ty.clone()); - } - trait_ref - } - - fn into_canonicalized(self, result: T) -> Canonicalized { - Canonicalized { - value: Canonical { value: result, num_vars: self.free_vars.len() }, - free_vars: self.free_vars, - } - } - - fn do_canonicalize_projection_ty(&mut self, mut projection_ty: ProjectionTy) -> ProjectionTy { - for ty in make_mut_slice(&mut projection_ty.parameters.0) { - *ty = self.do_canonicalize_ty(ty.clone()); - } - projection_ty - } - - fn do_canonicalize_projection_predicate( - &mut self, - projection: ProjectionPredicate, - ) -> ProjectionPredicate { - let ty = self.do_canonicalize_ty(projection.ty); - let projection_ty = self.do_canonicalize_projection_ty(projection.projection_ty); - - ProjectionPredicate { ty, projection_ty } - } - - // FIXME: add some point, we need to introduce a `Fold` trait that abstracts - // over all the things that can be canonicalized (like Chalk and rustc have) - - pub(crate) fn canonicalize_ty(mut self, ty: Ty) -> Canonicalized { - let result = self.do_canonicalize_ty(ty); - self.into_canonicalized(result) - } - - pub(crate) fn canonicalize_obligation( - mut self, - obligation: InEnvironment, - ) -> Canonicalized> { - let result = match obligation.value { - Obligation::Trait(tr) => Obligation::Trait(self.do_canonicalize_trait_ref(tr)), - Obligation::Projection(pr) => { - Obligation::Projection(self.do_canonicalize_projection_predicate(pr)) - } - }; - self.into_canonicalized(InEnvironment { - value: result, - environment: obligation.environment, - }) - } -} - -impl Canonicalized { - pub fn decanonicalize_ty(&self, mut ty: Ty) -> Ty { - ty.walk_mut_binders( - &mut |ty, binders| match ty { - &mut Ty::Bound(idx) => { - if idx as usize >= binders && (idx as usize - binders) < self.free_vars.len() { - *ty = Ty::Infer(self.free_vars[idx as usize - binders]); - } - } - _ => {} - }, - 0, - ); - ty - } - - pub fn apply_solution( - &self, - ctx: &mut InferenceContext<'_, impl HirDatabase>, - solution: Canonical>, - ) { - // the solution may contain new variables, which we need to convert to new inference vars - let new_vars = Substs((0..solution.num_vars).map(|_| ctx.new_type_var()).collect()); - for (i, ty) in solution.value.into_iter().enumerate() { - let var = self.free_vars[i]; - ctx.unify(&Ty::Infer(var), &ty.subst_bound_vars(&new_vars)); - } - } -} -- cgit v1.2.3