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author | bors[bot] <26634292+bors[bot]@users.noreply.github.com> | 2021-04-30 10:07:24 +0100 |
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committer | GitHub <[email protected]> | 2021-04-30 10:07:24 +0100 |
commit | b5b4a1f23dd4d544eec0699bda9df39235617711 (patch) | |
tree | 155a638a9cb73ddce1df6ce0c7b43fe4d4b12c69 /crates | |
parent | 6ea91a419f89e2486938d139daf8eb8620444944 (diff) | |
parent | c2aefd5b95adb9e07919a11cdfcca45de79b5324 (diff) |
Merge #8692
8692: Fix panic caused by new Try trait definition r=flodiebold a=flodiebold
The new Try trait definition caused a query cycle for us. This adds recovery for that cycle, but also fixes the cause, which is that we went through the supertraits when resolving `<T as Trait>::Assoc`, which isn't actually necessary. I also rewrote `all_super_trait_refs` to an iterator before I realized what the actual problem was, so I kept that.
Fixes #8686.
Co-authored-by: Florian Diebold <[email protected]>
Diffstat (limited to 'crates')
-rw-r--r-- | crates/hir_ty/src/db.rs | 1 | ||||
-rw-r--r-- | crates/hir_ty/src/lower.rs | 34 | ||||
-rw-r--r-- | crates/hir_ty/src/tests/regression.rs | 38 | ||||
-rw-r--r-- | crates/hir_ty/src/utils.rs | 52 |
4 files changed, 100 insertions, 25 deletions
diff --git a/crates/hir_ty/src/db.rs b/crates/hir_ty/src/db.rs index cf67d4266..9da0a02e3 100644 --- a/crates/hir_ty/src/db.rs +++ b/crates/hir_ty/src/db.rs | |||
@@ -70,6 +70,7 @@ pub trait HirDatabase: DefDatabase + Upcast<dyn DefDatabase> { | |||
70 | fn trait_environment(&self, def: GenericDefId) -> Arc<crate::TraitEnvironment>; | 70 | fn trait_environment(&self, def: GenericDefId) -> Arc<crate::TraitEnvironment>; |
71 | 71 | ||
72 | #[salsa::invoke(crate::lower::generic_defaults_query)] | 72 | #[salsa::invoke(crate::lower::generic_defaults_query)] |
73 | #[salsa::cycle(crate::lower::generic_defaults_recover)] | ||
73 | fn generic_defaults(&self, def: GenericDefId) -> Arc<[Binders<Ty>]>; | 74 | fn generic_defaults(&self, def: GenericDefId) -> Arc<[Binders<Ty>]>; |
74 | 75 | ||
75 | #[salsa::invoke(InherentImpls::inherent_impls_in_crate_query)] | 76 | #[salsa::invoke(InherentImpls::inherent_impls_in_crate_query)] |
diff --git a/crates/hir_ty/src/lower.rs b/crates/hir_ty/src/lower.rs index 7fd46becd..c99dd8d0a 100644 --- a/crates/hir_ty/src/lower.rs +++ b/crates/hir_ty/src/lower.rs | |||
@@ -414,17 +414,16 @@ impl<'a> TyLoweringContext<'a> { | |||
414 | self.lower_trait_ref_from_resolved_path(trait_, resolved_segment, self_ty); | 414 | self.lower_trait_ref_from_resolved_path(trait_, resolved_segment, self_ty); |
415 | let ty = if remaining_segments.len() == 1 { | 415 | let ty = if remaining_segments.len() == 1 { |
416 | let segment = remaining_segments.first().unwrap(); | 416 | let segment = remaining_segments.first().unwrap(); |
417 | let found = associated_type_by_name_including_super_traits( | 417 | let found = self |
418 | self.db, | 418 | .db |
419 | trait_ref, | 419 | .trait_data(trait_ref.hir_trait_id()) |
420 | &segment.name, | 420 | .associated_type_by_name(&segment.name); |
421 | ); | ||
422 | match found { | 421 | match found { |
423 | Some((super_trait_ref, associated_ty)) => { | 422 | Some(associated_ty) => { |
424 | // FIXME handle type parameters on the segment | 423 | // FIXME handle type parameters on the segment |
425 | TyKind::Alias(AliasTy::Projection(ProjectionTy { | 424 | TyKind::Alias(AliasTy::Projection(ProjectionTy { |
426 | associated_ty_id: to_assoc_type_id(associated_ty), | 425 | associated_ty_id: to_assoc_type_id(associated_ty), |
427 | substitution: super_trait_ref.substitution, | 426 | substitution: trait_ref.substitution, |
428 | })) | 427 | })) |
429 | .intern(&Interner) | 428 | .intern(&Interner) |
430 | } | 429 | } |
@@ -1089,6 +1088,27 @@ pub(crate) fn generic_defaults_query( | |||
1089 | defaults | 1088 | defaults |
1090 | } | 1089 | } |
1091 | 1090 | ||
1091 | pub(crate) fn generic_defaults_recover( | ||
1092 | db: &dyn HirDatabase, | ||
1093 | _cycle: &[String], | ||
1094 | def: &GenericDefId, | ||
1095 | ) -> Arc<[Binders<Ty>]> { | ||
1096 | let generic_params = generics(db.upcast(), *def); | ||
1097 | |||
1098 | // we still need one default per parameter | ||
1099 | let defaults = generic_params | ||
1100 | .iter() | ||
1101 | .enumerate() | ||
1102 | .map(|(idx, _)| { | ||
1103 | let ty = TyKind::Error.intern(&Interner); | ||
1104 | |||
1105 | crate::make_only_type_binders(idx, ty) | ||
1106 | }) | ||
1107 | .collect(); | ||
1108 | |||
1109 | defaults | ||
1110 | } | ||
1111 | |||
1092 | fn fn_sig_for_fn(db: &dyn HirDatabase, def: FunctionId) -> PolyFnSig { | 1112 | fn fn_sig_for_fn(db: &dyn HirDatabase, def: FunctionId) -> PolyFnSig { |
1093 | let data = db.function_data(def); | 1113 | let data = db.function_data(def); |
1094 | let resolver = def.resolver(db.upcast()); | 1114 | let resolver = def.resolver(db.upcast()); |
diff --git a/crates/hir_ty/src/tests/regression.rs b/crates/hir_ty/src/tests/regression.rs index 9cd9f473d..d14f5c9bb 100644 --- a/crates/hir_ty/src/tests/regression.rs +++ b/crates/hir_ty/src/tests/regression.rs | |||
@@ -1012,3 +1012,41 @@ fn lifetime_from_chalk_during_deref() { | |||
1012 | "#, | 1012 | "#, |
1013 | ) | 1013 | ) |
1014 | } | 1014 | } |
1015 | |||
1016 | #[test] | ||
1017 | fn issue_8686() { | ||
1018 | check_infer( | ||
1019 | r#" | ||
1020 | pub trait Try: FromResidual { | ||
1021 | type Output; | ||
1022 | type Residual; | ||
1023 | } | ||
1024 | pub trait FromResidual<R = <Self as Try>::Residual> { | ||
1025 | fn from_residual(residual: R) -> Self; | ||
1026 | } | ||
1027 | |||
1028 | struct ControlFlow<B, C>; | ||
1029 | impl<B, C> Try for ControlFlow<B, C> { | ||
1030 | type Output = C; | ||
1031 | type Residual = ControlFlow<B, !>; | ||
1032 | } | ||
1033 | impl<B, C> FromResidual for ControlFlow<B, C> { | ||
1034 | fn from_residual(r: ControlFlow<B, !>) -> Self { ControlFlow } | ||
1035 | } | ||
1036 | |||
1037 | fn test() { | ||
1038 | ControlFlow::from_residual(ControlFlow::<u32, !>); | ||
1039 | } | ||
1040 | "#, | ||
1041 | expect![[r#" | ||
1042 | 144..152 'residual': R | ||
1043 | 365..366 'r': ControlFlow<B, !> | ||
1044 | 395..410 '{ ControlFlow }': ControlFlow<B, C> | ||
1045 | 397..408 'ControlFlow': ControlFlow<B, C> | ||
1046 | 424..482 '{ ...!>); }': () | ||
1047 | 430..456 'Contro...sidual': fn from_residual<ControlFlow<u32, {unknown}>, ControlFlow<u32, !>>(ControlFlow<u32, !>) -> ControlFlow<u32, {unknown}> | ||
1048 | 430..479 'Contro...2, !>)': ControlFlow<u32, {unknown}> | ||
1049 | 457..478 'Contro...32, !>': ControlFlow<u32, !> | ||
1050 | "#]], | ||
1051 | ); | ||
1052 | } | ||
diff --git a/crates/hir_ty/src/utils.rs b/crates/hir_ty/src/utils.rs index 2f04ee57a..2f490fb92 100644 --- a/crates/hir_ty/src/utils.rs +++ b/crates/hir_ty/src/utils.rs | |||
@@ -1,6 +1,8 @@ | |||
1 | //! Helper functions for working with def, which don't need to be a separate | 1 | //! Helper functions for working with def, which don't need to be a separate |
2 | //! query, but can't be computed directly from `*Data` (ie, which need a `db`). | 2 | //! query, but can't be computed directly from `*Data` (ie, which need a `db`). |
3 | 3 | ||
4 | use std::iter; | ||
5 | |||
4 | use chalk_ir::{fold::Shift, BoundVar, DebruijnIndex}; | 6 | use chalk_ir::{fold::Shift, BoundVar, DebruijnIndex}; |
5 | use hir_def::{ | 7 | use hir_def::{ |
6 | db::DefDatabase, | 8 | db::DefDatabase, |
@@ -14,8 +16,12 @@ use hir_def::{ | |||
14 | AssocContainerId, GenericDefId, Lookup, TraitId, TypeAliasId, TypeParamId, | 16 | AssocContainerId, GenericDefId, Lookup, TraitId, TypeAliasId, TypeParamId, |
15 | }; | 17 | }; |
16 | use hir_expand::name::{name, Name}; | 18 | use hir_expand::name::{name, Name}; |
19 | use rustc_hash::FxHashSet; | ||
17 | 20 | ||
18 | use crate::{db::HirDatabase, Interner, Substitution, TraitRef, TraitRefExt, TyKind, WhereClause}; | 21 | use crate::{ |
22 | db::HirDatabase, ChalkTraitId, Interner, Substitution, TraitRef, TraitRefExt, TyKind, | ||
23 | WhereClause, | ||
24 | }; | ||
19 | 25 | ||
20 | fn direct_super_traits(db: &dyn DefDatabase, trait_: TraitId) -> Vec<TraitId> { | 26 | fn direct_super_traits(db: &dyn DefDatabase, trait_: TraitId) -> Vec<TraitId> { |
21 | let resolver = trait_.resolver(db); | 27 | let resolver = trait_.resolver(db); |
@@ -102,25 +108,35 @@ pub fn all_super_traits(db: &dyn DefDatabase, trait_: TraitId) -> Vec<TraitId> { | |||
102 | /// `all_super_traits` is that we keep track of type parameters; for example if | 108 | /// `all_super_traits` is that we keep track of type parameters; for example if |
103 | /// we have `Self: Trait<u32, i32>` and `Trait<T, U>: OtherTrait<U>` we'll get | 109 | /// we have `Self: Trait<u32, i32>` and `Trait<T, U>: OtherTrait<U>` we'll get |
104 | /// `Self: OtherTrait<i32>`. | 110 | /// `Self: OtherTrait<i32>`. |
105 | pub(super) fn all_super_trait_refs(db: &dyn HirDatabase, trait_ref: TraitRef) -> Vec<TraitRef> { | 111 | pub(super) fn all_super_trait_refs(db: &dyn HirDatabase, trait_ref: TraitRef) -> SuperTraits { |
106 | // FIXME: replace by Chalk's `super_traits`, maybe make this a query | 112 | SuperTraits { db, seen: iter::once(trait_ref.trait_id).collect(), stack: vec![trait_ref] } |
113 | } | ||
107 | 114 | ||
108 | // we need to take care a bit here to avoid infinite loops in case of cycles | 115 | pub(super) struct SuperTraits<'a> { |
109 | // (i.e. if we have `trait A: B; trait B: A;`) | 116 | db: &'a dyn HirDatabase, |
110 | let mut result = vec![trait_ref]; | 117 | stack: Vec<TraitRef>, |
111 | let mut i = 0; | 118 | seen: FxHashSet<ChalkTraitId>, |
112 | while i < result.len() { | 119 | } |
113 | let t = &result[i]; | 120 | |
114 | // yeah this is quadratic, but trait hierarchies should be flat | 121 | impl<'a> SuperTraits<'a> { |
115 | // enough that this doesn't matter | 122 | fn elaborate(&mut self, trait_ref: &TraitRef) { |
116 | for tt in direct_super_trait_refs(db, t) { | 123 | let mut trait_refs = direct_super_trait_refs(self.db, trait_ref); |
117 | if !result.iter().any(|tr| tr.trait_id == tt.trait_id) { | 124 | trait_refs.retain(|tr| !self.seen.contains(&tr.trait_id)); |
118 | result.push(tt); | 125 | self.stack.extend(trait_refs); |
119 | } | 126 | } |
127 | } | ||
128 | |||
129 | impl<'a> Iterator for SuperTraits<'a> { | ||
130 | type Item = TraitRef; | ||
131 | |||
132 | fn next(&mut self) -> Option<Self::Item> { | ||
133 | if let Some(next) = self.stack.pop() { | ||
134 | self.elaborate(&next); | ||
135 | Some(next) | ||
136 | } else { | ||
137 | None | ||
120 | } | 138 | } |
121 | i += 1; | ||
122 | } | 139 | } |
123 | result | ||
124 | } | 140 | } |
125 | 141 | ||
126 | pub(super) fn associated_type_by_name_including_super_traits( | 142 | pub(super) fn associated_type_by_name_including_super_traits( |
@@ -128,7 +144,7 @@ pub(super) fn associated_type_by_name_including_super_traits( | |||
128 | trait_ref: TraitRef, | 144 | trait_ref: TraitRef, |
129 | name: &Name, | 145 | name: &Name, |
130 | ) -> Option<(TraitRef, TypeAliasId)> { | 146 | ) -> Option<(TraitRef, TypeAliasId)> { |
131 | all_super_trait_refs(db, trait_ref).into_iter().find_map(|t| { | 147 | all_super_trait_refs(db, trait_ref).find_map(|t| { |
132 | let assoc_type = db.trait_data(t.hir_trait_id()).associated_type_by_name(name)?; | 148 | let assoc_type = db.trait_data(t.hir_trait_id()).associated_type_by_name(name)?; |
133 | Some((t, assoc_type)) | 149 | Some((t, assoc_type)) |
134 | }) | 150 | }) |