Unnamed repository; edit this file 'description' to name the repository.
Don't attempt to compute implict sized clauses for empty generics
| -rw-r--r-- | crates/hir-ty/src/lower.rs | 83 |
1 files changed, 46 insertions, 37 deletions
diff --git a/crates/hir-ty/src/lower.rs b/crates/hir-ty/src/lower.rs index 6beb4871da..4942244396 100644 --- a/crates/hir-ty/src/lower.rs +++ b/crates/hir-ty/src/lower.rs @@ -48,6 +48,7 @@ use intern::Interned; use la_arena::{Arena, ArenaMap}; use once_cell::unsync::OnceCell; use rustc_hash::FxHashSet; +use rustc_pattern_analysis::Captures; use smallvec::SmallVec; use stdx::{impl_from, never}; use syntax::ast; @@ -1595,14 +1596,20 @@ pub(crate) fn generic_predicates_for_param_query( .collect(); let subst = generics.bound_vars_subst(db, DebruijnIndex::INNERMOST); - let explicitly_unsized_tys = ctx.unsized_types.into_inner(); - if let Some(implicitly_sized_predicates) = - implicitly_sized_clauses(db, param_id.parent, &explicitly_unsized_tys, &subst, &resolver) - { - predicates.extend( - implicitly_sized_predicates - .map(|p| make_binders(db, &generics, crate::wrap_empty_binders(p))), - ); + if !subst.is_empty(Interner) { + let explicitly_unsized_tys = ctx.unsized_types.into_inner(); + if let Some(implicitly_sized_predicates) = implicitly_sized_clauses( + db, + param_id.parent, + &explicitly_unsized_tys, + &subst, + &resolver, + ) { + predicates.extend( + implicitly_sized_predicates + .map(|p| make_binders(db, &generics, crate::wrap_empty_binders(p))), + ); + }; } predicates.into() } @@ -1665,14 +1672,17 @@ pub(crate) fn trait_environment_query( } let subst = generics(db.upcast(), def).placeholder_subst(db); - let explicitly_unsized_tys = ctx.unsized_types.into_inner(); - if let Some(implicitly_sized_clauses) = - implicitly_sized_clauses(db, def, &explicitly_unsized_tys, &subst, &resolver) - { - clauses.extend( - implicitly_sized_clauses - .map(|pred| pred.cast::<ProgramClause>(Interner).into_from_env_clause(Interner)), - ); + if !subst.is_empty(Interner) { + let explicitly_unsized_tys = ctx.unsized_types.into_inner(); + if let Some(implicitly_sized_clauses) = + implicitly_sized_clauses(db, def, &explicitly_unsized_tys, &subst, &resolver) + { + clauses.extend( + implicitly_sized_clauses.map(|pred| { + pred.cast::<ProgramClause>(Interner).into_from_env_clause(Interner) + }), + ); + }; } let env = chalk_ir::Environment::new(Interner).add_clauses(Interner, clauses); @@ -1714,27 +1724,29 @@ pub(crate) fn generic_predicates_query( .collect::<Vec<_>>(); let subst = generics.bound_vars_subst(db, DebruijnIndex::INNERMOST); - let explicitly_unsized_tys = ctx.unsized_types.into_inner(); - if let Some(implicitly_sized_predicates) = - implicitly_sized_clauses(db, def, &explicitly_unsized_tys, &subst, &resolver) - { - predicates.extend( - implicitly_sized_predicates - .map(|p| make_binders(db, &generics, crate::wrap_empty_binders(p))), - ); + if !subst.is_empty(Interner) { + let explicitly_unsized_tys = ctx.unsized_types.into_inner(); + if let Some(implicitly_sized_predicates) = + implicitly_sized_clauses(db, def, &explicitly_unsized_tys, &subst, &resolver) + { + predicates.extend( + implicitly_sized_predicates + .map(|p| make_binders(db, &generics, crate::wrap_empty_binders(p))), + ); + }; } GenericPredicates(predicates.is_empty().not().then(|| predicates.into())) } /// Generate implicit `: Sized` predicates for all generics that has no `?Sized` bound. /// Exception is Self of a trait def. -fn implicitly_sized_clauses<'a>( +fn implicitly_sized_clauses<'a, 'subst: 'a>( db: &dyn HirDatabase, def: GenericDefId, explicitly_unsized_tys: &'a FxHashSet<Ty>, - substitution: &'a Substitution, + substitution: &'subst Substitution, resolver: &Resolver, -) -> Option<impl Iterator<Item = WhereClause> + 'a> { +) -> Option<impl Iterator<Item = WhereClause> + Captures<'a> + Captures<'subst>> { let is_trait_def = matches!(def, GenericDefId::TraitId(..)); let generic_args = &substitution.as_slice(Interner)[is_trait_def as usize..]; let sized_trait = db @@ -1761,12 +1773,13 @@ pub(crate) fn generic_defaults_query( def: GenericDefId, ) -> Arc<[Binders<crate::GenericArg>]> { let resolver = def.resolver(db.upcast()); - let ctx = TyLoweringContext::new(db, &resolver, def.into()) - .with_type_param_mode(ParamLoweringMode::Variable); let generic_params = generics(db.upcast(), def); let parent_start_idx = generic_params.len_self(); - let defaults = Arc::from_iter(generic_params.iter().enumerate().map(|(idx, (id, p))| { + let ctx = TyLoweringContext::new(db, &resolver, def.into()) + .with_impl_trait_mode(ImplTraitLoweringMode::Disallowed) + .with_type_param_mode(ParamLoweringMode::Variable); + Arc::from_iter(generic_params.iter().enumerate().map(|(idx, (id, p))| { match p { GenericParamDataRef::TypeParamData(p) => { let mut ty = @@ -1797,9 +1810,7 @@ pub(crate) fn generic_defaults_query( make_binders(db, &generic_params, error_lifetime().cast(Interner)) } } - })); - - defaults + })) } pub(crate) fn generic_defaults_recover( @@ -1810,16 +1821,14 @@ pub(crate) fn generic_defaults_recover( let generic_params = generics(db.upcast(), *def); // FIXME: this code is not covered in tests. // we still need one default per parameter - let defaults = Arc::from_iter(generic_params.iter_id().map(|id| { + Arc::from_iter(generic_params.iter_id().map(|id| { let val = match id { GenericParamId::TypeParamId(_) => TyKind::Error.intern(Interner).cast(Interner), GenericParamId::ConstParamId(id) => unknown_const_as_generic(db.const_param_ty(id)), GenericParamId::LifetimeParamId(_) => error_lifetime().cast(Interner), }; crate::make_binders(db, &generic_params, val) - })); - - defaults + })) } fn fn_sig_for_fn(db: &dyn HirDatabase, def: FunctionId) -> PolyFnSig { |