Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/infer/coerce.rs')
| -rw-r--r-- | crates/hir-ty/src/infer/coerce.rs | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/crates/hir-ty/src/infer/coerce.rs b/crates/hir-ty/src/infer/coerce.rs index 761a2564aa..631a91bac4 100644 --- a/crates/hir-ty/src/infer/coerce.rs +++ b/crates/hir-ty/src/infer/coerce.rs @@ -13,14 +13,15 @@ use stdx::always; use triomphe::Arc; use crate::{ - Canonical, DomainGoal, FnAbi, FnPointer, FnSig, Guidance, InEnvironment, Interner, Lifetime, - Solution, Substitution, TraitEnvironment, Ty, TyBuilder, TyExt, + Canonical, DomainGoal, FnAbi, FnPointer, FnSig, InEnvironment, Interner, Lifetime, + Substitution, TraitEnvironment, Ty, TyBuilder, TyExt, autoderef::{Autoderef, AutoderefKind}, db::HirDatabase, infer::{ Adjust, Adjustment, AutoBorrow, InferOk, InferenceContext, OverloadedDeref, PointerCast, TypeError, TypeMismatch, }, + traits::NextTraitSolveResult, utils::ClosureSubst, }; @@ -715,13 +716,18 @@ impl InferenceTable<'_> { // solve `CoerceUnsized` and `Unsize` goals at this point and leaves the // rest for later. Also, there's some logic about sized type variables. // Need to find out in what cases this is necessary - let solution = self - .db - .trait_solve(krate, self.trait_env.block, canonicalized.value.clone().cast(Interner)) - .ok_or(TypeError)?; + let solution = self.db.trait_solve( + krate, + self.trait_env.block, + canonicalized.value.clone().cast(Interner), + ); match solution { - Solution::Unique(v) => { + // FIXME: this is a weaker guarantee than Chalk's `Guidance::Unique` + // was. Chalk's unique guidance at least guarantees that the real solution + // is some "subset" of the solutions matching the guidance, but the + // substs for `Certainty::No` don't have that same guarantee (I think). + NextTraitSolveResult::Certain(v) => { canonicalized.apply_solution( self, Canonical { @@ -731,13 +737,12 @@ impl InferenceTable<'_> { }, ); } - Solution::Ambig(Guidance::Definite(subst)) => { - // FIXME need to record an obligation here - canonicalized.apply_solution(self, subst) + // ...so, should think about how to get some actually get some guidance here + NextTraitSolveResult::Uncertain(..) | NextTraitSolveResult::NoSolution => { + return Err(TypeError); } - // FIXME actually we maybe should also accept unknown guidance here - _ => return Err(TypeError), - }; + } + let unsize = Adjustment { kind: Adjust::Pointer(PointerCast::Unsize), target: to_ty.clone() }; let adjustments = match reborrow { |