diff --git a/compiler/rustc_error_codes/src/error_codes/E0801.md b/compiler/rustc_error_codes/src/error_codes/E0801.md new file mode 100644 index 00000000000..c89feb9b308 --- /dev/null +++ b/compiler/rustc_error_codes/src/error_codes/E0801.md @@ -0,0 +1,51 @@ +The `self` parameter in a method has an invalid generic "receiver type". + +Erroneous code example: + +```compile_fail,E0801 +struct Foo; + +impl Foo { + fn foo>(self: R) {} +} +``` + +or alternatively, + +```compile_fail,E0801 +struct Foo; + +impl Foo { + fn foo(self: impl std::ops::Deref) {} +} +``` + +Methods take a special first parameter, termed `self`. It's normal to +use `self`, `&self` or `&mut self`, which are syntactic sugar for +`self: Self`, `self: &Self`, and `self: &mut Self` respectively. +But it's also possible to use more sophisticated types of `self` +parameter, for instance `std::rc::Rc`. The set of allowable +`Self` types is extensible using the nightly feature +[Arbitrary self types][AST]. +This will extend the valid set of `Self` types to anything which implements +`std::ops::Deref`, for example `Rc`, `Box`, or +your own smart pointers that do the same. + +However, even with that feature, the `self` type must be concrete. +Generic `self` types are not permitted. Specifically, a `self` type will +be rejected if it is a type parameter defined on the method. + +These are OK: + +``` +struct Foo; + +impl Foo { + fn foo(self) {} + fn foo2(self: std::rc::Rc) {} // or some other similar + // smart pointer if you enable arbitrary self types and + // the pointer implements Deref +} +``` + +[AST]: https://doc.rust-lang.org/unstable-book/language-features/arbitrary-self-types.html diff --git a/compiler/rustc_error_codes/src/lib.rs b/compiler/rustc_error_codes/src/lib.rs index 27a34d6003d..29f3277d399 100644 --- a/compiler/rustc_error_codes/src/lib.rs +++ b/compiler/rustc_error_codes/src/lib.rs @@ -540,6 +540,7 @@ macro_rules! error_codes { E0798: 0798, E0799: 0799, E0800: 0800, +E0801: 0801, ); ) } diff --git a/compiler/rustc_hir_analysis/messages.ftl b/compiler/rustc_hir_analysis/messages.ftl index 7191c724061..38b11aa4017 100644 --- a/compiler/rustc_hir_analysis/messages.ftl +++ b/compiler/rustc_hir_analysis/messages.ftl @@ -234,6 +234,12 @@ hir_analysis_inherent_ty_outside_relevant = cannot define inherent `impl` for a .help = consider moving this inherent impl into the crate defining the type if possible .span_help = alternatively add `#[rustc_allow_incoherent_impl]` to the relevant impl items +hir_analysis_invalid_generic_receiver_ty = invalid generic `self` parameter type: `{$receiver_ty}` + .note = type of `self` must not be a method generic parameter type + +hir_analysis_invalid_generic_receiver_ty_help = + use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + hir_analysis_invalid_receiver_ty = invalid `self` parameter type: `{$receiver_ty}` .note = type of `self` must be `Self` or a type that dereferences to it diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs index 12ed7b89f68..5bc320b12b0 100644 --- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs +++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs @@ -2,13 +2,14 @@ use std::ops::{ControlFlow, Deref}; use hir::intravisit::{self, Visitor}; +use itertools::Itertools; use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet}; use rustc_errors::codes::*; use rustc_errors::{Applicability, ErrorGuaranteed, pluralize, struct_span_code_err}; -use rustc_hir::ItemKind; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::{DefId, LocalDefId, LocalModDefId}; use rustc_hir::lang_items::LangItem; +use rustc_hir::{GenericParamKind, ItemKind}; use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt}; use rustc_macros::LintDiagnostic; @@ -378,7 +379,7 @@ fn check_trait_item<'tcx>( _ => (None, trait_item.span), }; check_dyn_incompatible_self_trait_by_name(tcx, trait_item); - let mut res = check_associated_item(tcx, def_id, span, method_sig); + let mut res = check_associated_item(tcx, def_id, span, method_sig, None); if matches!(trait_item.kind, hir::TraitItemKind::Fn(..)) { for &assoc_ty_def_id in tcx.associated_types_for_impl_traits_in_associated_fn(def_id) { @@ -387,6 +388,7 @@ fn check_trait_item<'tcx>( assoc_ty_def_id.expect_local(), tcx.def_span(assoc_ty_def_id), None, + None, )); } } @@ -904,8 +906,13 @@ fn check_impl_item<'tcx>( hir::ImplItemKind::Type(ty) if ty.span != DUMMY_SP => (None, ty.span), _ => (None, impl_item.span), }; - - check_associated_item(tcx, impl_item.owner_id.def_id, span, method_sig) + check_associated_item( + tcx, + impl_item.owner_id.def_id, + span, + method_sig, + Some(impl_item.generics), + ) } fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) -> Result<(), ErrorGuaranteed> { @@ -1038,6 +1045,7 @@ fn check_associated_item( item_id: LocalDefId, span: Span, sig_if_method: Option<&hir::FnSig<'_>>, + generics: Option<&hir::Generics<'_>>, ) -> Result<(), ErrorGuaranteed> { let loc = Some(WellFormedLoc::Ty(item_id)); enter_wf_checking_ctxt(tcx, span, item_id, |wfcx| { @@ -1070,7 +1078,7 @@ fn check_associated_item( hir_sig.decl, item.def_id.expect_local(), ); - check_method_receiver(wfcx, hir_sig, item, self_ty) + check_method_receiver(wfcx, hir_sig, item, self_ty, generics) } ty::AssocKind::Type => { if let ty::AssocItemContainer::TraitContainer = item.container { @@ -1692,6 +1700,7 @@ fn check_method_receiver<'tcx>( fn_sig: &hir::FnSig<'_>, method: ty::AssocItem, self_ty: Ty<'tcx>, + generics: Option<&hir::Generics<'_>>, ) -> Result<(), ErrorGuaranteed> { let tcx = wfcx.tcx(); @@ -1726,7 +1735,9 @@ fn check_method_receiver<'tcx>( None }; - if !receiver_is_valid(wfcx, span, receiver_ty, self_ty, arbitrary_self_types_level) { + let receiver_validity = + receiver_is_valid(wfcx, span, receiver_ty, self_ty, arbitrary_self_types_level, generics); + if let Err(receiver_validity_err) = receiver_validity { return Err(match arbitrary_self_types_level { // Wherever possible, emit a message advising folks that the features // `arbitrary_self_types` or `arbitrary_self_types_pointers` might @@ -1737,7 +1748,9 @@ fn check_method_receiver<'tcx>( receiver_ty, self_ty, Some(ArbitrarySelfTypesLevel::Basic), - ) => + generics, + ) + .is_ok() => { // Report error; would have worked with `arbitrary_self_types`. feature_err( @@ -1759,7 +1772,9 @@ fn check_method_receiver<'tcx>( receiver_ty, self_ty, Some(ArbitrarySelfTypesLevel::WithPointers), - ) => + generics, + ) + .is_ok() => { // Report error; would have worked with `arbitrary_self_types_pointers`. feature_err( @@ -1777,13 +1792,53 @@ fn check_method_receiver<'tcx>( _ => // Report error; would not have worked with `arbitrary_self_types[_pointers]`. { - tcx.dcx().emit_err(errors::InvalidReceiverTy { span, receiver_ty }) + match receiver_validity_err { + ReceiverValidityError::DoesNotDeref => { + tcx.dcx().emit_err(errors::InvalidReceiverTy { span, receiver_ty }) + } + ReceiverValidityError::MethodGenericParamUsed => { + tcx.dcx().emit_err(errors::InvalidGenericReceiverTy { span, receiver_ty }) + } + } } }); } Ok(()) } +/// Error cases which may be returned from `receiver_is_valid`. These error +/// cases are generated in this function as they may be unearthed as we explore +/// the `autoderef` chain, but they're converted to diagnostics in the caller. +enum ReceiverValidityError { + /// The self type does not get to the receiver type by following the + /// autoderef chain. + DoesNotDeref, + /// A type was found which is a method type parameter, and that's not allowed. + MethodGenericParamUsed, +} + +/// Confirms that a type is not a type parameter referring to one of the +/// method's type params. +fn confirm_type_is_not_a_method_generic_param( + ty: Ty<'_>, + method_generics: Option<&hir::Generics<'_>>, +) -> Result<(), ReceiverValidityError> { + if let ty::Param(param) = ty.kind() { + if let Some(generics) = method_generics { + if generics + .params + .iter() + .filter(|g| matches!(g.kind, GenericParamKind::Type { .. })) + .map(|g| g.name.ident().name) + .contains(¶m.name) + { + return Err(ReceiverValidityError::MethodGenericParamUsed); + } + } + } + Ok(()) +} + /// Returns whether `receiver_ty` would be considered a valid receiver type for `self_ty`. If /// `arbitrary_self_types` is enabled, `receiver_ty` must transitively deref to `self_ty`, possibly /// through a `*const/mut T` raw pointer if `arbitrary_self_types_pointers` is also enabled. @@ -1799,7 +1854,8 @@ fn receiver_is_valid<'tcx>( receiver_ty: Ty<'tcx>, self_ty: Ty<'tcx>, arbitrary_self_types_enabled: Option, -) -> bool { + generics: Option<&hir::Generics<'_>>, +) -> Result<(), ReceiverValidityError> { let infcx = wfcx.infcx; let tcx = wfcx.tcx(); let cause = @@ -1811,9 +1867,11 @@ fn receiver_is_valid<'tcx>( ocx.eq(&cause, wfcx.param_env, self_ty, receiver_ty)?; if ocx.select_all_or_error().is_empty() { Ok(()) } else { Err(NoSolution) } }) { - return true; + return Ok(()); } + confirm_type_is_not_a_method_generic_param(receiver_ty, generics)?; + let mut autoderef = Autoderef::new(infcx, wfcx.param_env, wfcx.body_def_id, span, receiver_ty); // The `arbitrary_self_types_pointers` feature allows raw pointer receivers like `self: *const Self`. @@ -1830,6 +1888,8 @@ fn receiver_is_valid<'tcx>( potential_self_ty, self_ty ); + confirm_type_is_not_a_method_generic_param(potential_self_ty, generics)?; + // Check if the self type unifies. If it does, then commit the result // since it may have region side-effects. if let Ok(()) = wfcx.infcx.commit_if_ok(|_| { @@ -1838,7 +1898,7 @@ fn receiver_is_valid<'tcx>( if ocx.select_all_or_error().is_empty() { Ok(()) } else { Err(NoSolution) } }) { wfcx.register_obligations(autoderef.into_obligations()); - return true; + return Ok(()); } // Without `feature(arbitrary_self_types)`, we require that each step in the @@ -1865,7 +1925,7 @@ fn receiver_is_valid<'tcx>( } debug!("receiver_is_valid: type `{:?}` does not deref to `{:?}`", receiver_ty, self_ty); - false + Err(ReceiverValidityError::DoesNotDeref) } fn receiver_is_implemented<'tcx>( diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs index 7fa9dfe346d..a92a5e4278c 100644 --- a/compiler/rustc_hir_analysis/src/errors.rs +++ b/compiler/rustc_hir_analysis/src/errors.rs @@ -1623,6 +1623,16 @@ pub(crate) struct InvalidReceiverTy<'tcx> { pub receiver_ty: Ty<'tcx>, } +#[derive(Diagnostic)] +#[diag(hir_analysis_invalid_generic_receiver_ty, code = E0801)] +#[note] +#[help(hir_analysis_invalid_generic_receiver_ty_help)] +pub(crate) struct InvalidGenericReceiverTy<'tcx> { + #[primary_span] + pub span: Span, + pub receiver_ty: Ty<'tcx>, +} + #[derive(Diagnostic)] #[diag(hir_analysis_cmse_inputs_stack_spill, code = E0798)] #[note] diff --git a/compiler/rustc_hir_typeck/src/method/confirm.rs b/compiler/rustc_hir_typeck/src/method/confirm.rs index f2b55d3aa4e..92b504d10bc 100644 --- a/compiler/rustc_hir_typeck/src/method/confirm.rs +++ b/compiler/rustc_hir_typeck/src/method/confirm.rs @@ -533,9 +533,6 @@ fn unify_receivers( self.register_predicates(obligations); } Err(terr) => { - // FIXME(arbitrary_self_types): We probably should limit the - // situations where this can occur by adding additional restrictions - // to the feature, like the self type can't reference method args. if self.tcx.features().arbitrary_self_types() { self.err_ctxt() .report_mismatched_types( diff --git a/src/tools/tidy/src/issues.txt b/src/tools/tidy/src/issues.txt index 94f8d23c158..932a58788e0 100644 --- a/src/tools/tidy/src/issues.txt +++ b/src/tools/tidy/src/issues.txt @@ -4102,7 +4102,6 @@ ui/type-alias-impl-trait/issue-53678-coroutine-and-const-fn.rs ui/type-alias-impl-trait/issue-55099-lifetime-inference.rs ui/type-alias-impl-trait/issue-57188-associate-impl-capture.rs ui/type-alias-impl-trait/issue-57611-trait-alias.rs -ui/type-alias-impl-trait/issue-57700.rs ui/type-alias-impl-trait/issue-57807-associated-type.rs ui/type-alias-impl-trait/issue-57961.rs ui/type-alias-impl-trait/issue-58662-coroutine-with-lifetime.rs diff --git a/tests/ui/self/arbitrary-self-from-method-substs-ice.rs b/tests/ui/self/arbitrary-self-from-method-substs-ice.rs index a544c8ea0d1..d121a194be6 100644 --- a/tests/ui/self/arbitrary-self-from-method-substs-ice.rs +++ b/tests/ui/self/arbitrary-self-from-method-substs-ice.rs @@ -8,7 +8,7 @@ struct Foo(u32); impl Foo { const fn get>(self: R) -> u32 { - //~^ ERROR: `R` cannot be used as the type of `self` + //~^ ERROR invalid generic `self` parameter type //~| ERROR destructor of `R` cannot be evaluated at compile-time self.0 //~^ ERROR cannot call non-const fn `::deref` in constant function diff --git a/tests/ui/self/arbitrary-self-from-method-substs-ice.stderr b/tests/ui/self/arbitrary-self-from-method-substs-ice.stderr index 6ae60e7af47..7252b5890fd 100644 --- a/tests/ui/self/arbitrary-self-from-method-substs-ice.stderr +++ b/tests/ui/self/arbitrary-self-from-method-substs-ice.stderr @@ -15,18 +15,16 @@ LL | const fn get>(self: R) -> u32 { LL | } | - value is dropped here -error[E0658]: `R` cannot be used as the type of `self` without the `arbitrary_self_types` feature +error[E0801]: invalid generic `self` parameter type: `R` --> $DIR/arbitrary-self-from-method-substs-ice.rs:10:49 | LL | const fn get>(self: R) -> u32 { | ^ | - = note: see issue #44874 for more information - = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable - = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date - = help: consider changing to `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) error: aborting due to 3 previous errors -Some errors have detailed explanations: E0015, E0493, E0658. +Some errors have detailed explanations: E0015, E0493, E0801. For more information about an error, try `rustc --explain E0015`. diff --git a/tests/ui/self/arbitrary-self-from-method-substs.default.stderr b/tests/ui/self/arbitrary-self-from-method-substs.default.stderr index 4cc69666b88..5dc3a0b0234 100644 --- a/tests/ui/self/arbitrary-self-from-method-substs.default.stderr +++ b/tests/ui/self/arbitrary-self-from-method-substs.default.stderr @@ -1,14 +1,168 @@ -error[E0658]: `R` cannot be used as the type of `self` without the `arbitrary_self_types` feature - --> $DIR/arbitrary-self-from-method-substs.rs:8:43 +error[E0801]: invalid generic `self` parameter type: `R` + --> $DIR/arbitrary-self-from-method-substs.rs:9:43 | LL | fn get>(self: R) -> u32 { | ^ | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `&R` + --> $DIR/arbitrary-self-from-method-substs.rs:13:44 + | +LL | fn get1>(self: &R) -> u32 { + | ^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `&mut R` + --> $DIR/arbitrary-self-from-method-substs.rs:17:44 + | +LL | fn get2>(self: &mut R) -> u32 { + | ^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `Rc` + --> $DIR/arbitrary-self-from-method-substs.rs:21:44 + | +LL | fn get3>(self: std::rc::Rc) -> u32 { + | ^^^^^^^^^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `&Rc` + --> $DIR/arbitrary-self-from-method-substs.rs:25:44 + | +LL | fn get4>(self: &std::rc::Rc) -> u32 { + | ^^^^^^^^^^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `Rc<&R>` + --> $DIR/arbitrary-self-from-method-substs.rs:29:44 + | +LL | fn get5>(self: std::rc::Rc<&R>) -> u32 { + | ^^^^^^^^^^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0658]: `::Receiver` cannot be used as the type of `self` without the `arbitrary_self_types` feature + --> $DIR/arbitrary-self-from-method-substs.rs:33:37 + | +LL | fn get6(self: FR::Receiver, other: FR) -> u32 { + | ^^^^^^^^^^^^ + | = note: see issue #44874 for more information = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date = help: consider changing to `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) -error: aborting due to 1 previous error +error[E0658]: `R` cannot be used as the type of `self` without the `arbitrary_self_types` feature + --> $DIR/arbitrary-self-from-method-substs.rs:61:18 + | +LL | fn get(self: R) {} + | ^ + | + = note: see issue #44874 for more information + = help: add `#![feature(arbitrary_self_types)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date + = help: consider changing to `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) -For more information about this error, try `rustc --explain E0658`. +error[E0271]: type mismatch resolving `::Receiver == Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:92:9 + | +LL | foo.get6(Silly); + | ^^^^ type mismatch resolving `::Receiver == Foo` + | +note: expected this to be `Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:71:21 + | +LL | type Receiver = std::rc::Rc; + | ^^^^^^^^^^^^^^^^ + = note: expected struct `Foo` + found struct `Rc` + +error[E0271]: type mismatch resolving `::Receiver == &Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:96:9 + | +LL | foo.get6(Silly); + | ^^^^ type mismatch resolving `::Receiver == &Foo` + | +note: expected this to be `&Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:71:21 + | +LL | type Receiver = std::rc::Rc; + | ^^^^^^^^^^^^^^^^ + = note: expected reference `&Foo` + found struct `Rc` + +error[E0599]: the method `get` exists for struct `Rc>`, but its trait bounds were not satisfied + --> $DIR/arbitrary-self-from-method-substs.rs:100:7 + | +LL | struct Bar(std::marker::PhantomData); + | ------------- doesn't satisfy `Bar<_>: Deref` +... +LL | t.get(); + | ^^^ method cannot be called on `Rc>` due to unsatisfied trait bounds + | +note: the following trait bounds were not satisfied: + `<&Bar<_> as Deref>::Target = Bar<&Bar<_>>` + `<&Rc> as Deref>::Target = Bar<&Rc>>` + `<&mut Bar<_> as Deref>::Target = Bar<&mut Bar<_>>` + `<&mut Rc> as Deref>::Target = Bar<&mut Rc>>` + `> as Deref>::Target = Bar>>` + `Bar<_>: Deref` + --> $DIR/arbitrary-self-from-method-substs.rs:60:9 + | +LL | impl> Bar { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------ + | | | + | | unsatisfied trait bound introduced here + | unsatisfied trait bound introduced here +note: the trait `Deref` must be implemented + --> $SRC_DIR/core/src/ops/deref.rs:LL:COL + = help: items from traits can only be used if the trait is implemented and in scope + = note: the following trait defines an item `get`, perhaps you need to implement it: + candidate #1: `SliceIndex` + +error[E0599]: the method `get` exists for reference `&Rc>`, but its trait bounds were not satisfied + --> $DIR/arbitrary-self-from-method-substs.rs:108:7 + | +LL | struct Bar(std::marker::PhantomData); + | ------------- doesn't satisfy `Bar<_>: Deref` +... +LL | t.get(); + | ^^^ method cannot be called on `&Rc>` due to unsatisfied trait bounds + | +note: the following trait bounds were not satisfied: + `<&&Rc> as Deref>::Target = Bar<&&Rc>>` + `<&Bar<_> as Deref>::Target = Bar<&Bar<_>>` + `<&Rc> as Deref>::Target = Bar<&Rc>>` + `<&mut &Rc> as Deref>::Target = Bar<&mut &Rc>>` + `<&mut Bar<_> as Deref>::Target = Bar<&mut Bar<_>>` + `<&mut Rc> as Deref>::Target = Bar<&mut Rc>>` + `> as Deref>::Target = Bar>>` + `Bar<_>: Deref` + --> $DIR/arbitrary-self-from-method-substs.rs:60:9 + | +LL | impl> Bar { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------ + | | | + | | unsatisfied trait bound introduced here + | unsatisfied trait bound introduced here +note: the trait `Deref` must be implemented + --> $SRC_DIR/core/src/ops/deref.rs:LL:COL + = help: items from traits can only be used if the trait is implemented and in scope + = note: the following trait defines an item `get`, perhaps you need to implement it: + candidate #1: `SliceIndex` + +error: aborting due to 12 previous errors + +Some errors have detailed explanations: E0271, E0599, E0658, E0801. +For more information about an error, try `rustc --explain E0271`. diff --git a/tests/ui/self/arbitrary-self-from-method-substs.feature.stderr b/tests/ui/self/arbitrary-self-from-method-substs.feature.stderr index 44e553f1a06..6e864f44aa3 100644 --- a/tests/ui/self/arbitrary-self-from-method-substs.feature.stderr +++ b/tests/ui/self/arbitrary-self-from-method-substs.feature.stderr @@ -1,9 +1,179 @@ +error[E0801]: invalid generic `self` parameter type: `R` + --> $DIR/arbitrary-self-from-method-substs.rs:9:43 + | +LL | fn get>(self: R) -> u32 { + | ^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `&R` + --> $DIR/arbitrary-self-from-method-substs.rs:13:44 + | +LL | fn get1>(self: &R) -> u32 { + | ^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `&mut R` + --> $DIR/arbitrary-self-from-method-substs.rs:17:44 + | +LL | fn get2>(self: &mut R) -> u32 { + | ^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `Rc` + --> $DIR/arbitrary-self-from-method-substs.rs:21:44 + | +LL | fn get3>(self: std::rc::Rc) -> u32 { + | ^^^^^^^^^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `&Rc` + --> $DIR/arbitrary-self-from-method-substs.rs:25:44 + | +LL | fn get4>(self: &std::rc::Rc) -> u32 { + | ^^^^^^^^^^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + +error[E0801]: invalid generic `self` parameter type: `Rc<&R>` + --> $DIR/arbitrary-self-from-method-substs.rs:29:44 + | +LL | fn get5>(self: std::rc::Rc<&R>) -> u32 { + | ^^^^^^^^^^^^^^^ + | + = note: type of `self` must not be a method generic parameter type + = help: use a concrete type such as `self`, `&self`, `&mut self`, `self: Box`, `self: Rc`, `self: Arc`, or `self: Pin

` (where P is one of the previous types except `Self`) + error[E0308]: mismatched types - --> $DIR/arbitrary-self-from-method-substs.rs:16:5 + --> $DIR/arbitrary-self-from-method-substs.rs:76:5 | LL | foo.get::<&Foo>(); | ^^^ expected `&Foo`, found `Foo` -error: aborting due to 1 previous error +error[E0308]: mismatched types + --> $DIR/arbitrary-self-from-method-substs.rs:78:5 + | +LL | foo.get::>(); + | ^^^ expected `Rc`, found `Foo` + | + = note: expected struct `Rc` + found struct `Foo` -For more information about this error, try `rustc --explain E0308`. +error[E0308]: mismatched types + --> $DIR/arbitrary-self-from-method-substs.rs:84:5 + | +LL | smart_ptr.get::>(); + | ^^^^^^^^^ expected `SmartPtr2<'_, Foo>`, found `SmartPtr<'_, Foo>` + | + = note: expected struct `SmartPtr2<'_, Foo>` + found struct `SmartPtr<'_, Foo>` + +error[E0308]: mismatched types + --> $DIR/arbitrary-self-from-method-substs.rs:86:5 + | +LL | smart_ptr.get::<&Foo>(); + | ^^^^^^^^^ expected `&Foo`, found `SmartPtr<'_, Foo>` + | + = note: expected reference `&Foo` + found struct `SmartPtr<'_, Foo, >` + +error[E0271]: type mismatch resolving `::Receiver == Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:92:9 + | +LL | foo.get6(Silly); + | ^^^^ type mismatch resolving `::Receiver == Foo` + | +note: expected this to be `Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:71:21 + | +LL | type Receiver = std::rc::Rc; + | ^^^^^^^^^^^^^^^^ + = note: expected struct `Foo` + found struct `Rc` + +error[E0271]: type mismatch resolving `::Receiver == &Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:96:9 + | +LL | foo.get6(Silly); + | ^^^^ type mismatch resolving `::Receiver == &Foo` + | +note: expected this to be `&Foo` + --> $DIR/arbitrary-self-from-method-substs.rs:71:21 + | +LL | type Receiver = std::rc::Rc; + | ^^^^^^^^^^^^^^^^ + = note: expected reference `&Foo` + found struct `Rc` + +error[E0599]: the method `get` exists for struct `Rc>`, but its trait bounds were not satisfied + --> $DIR/arbitrary-self-from-method-substs.rs:100:7 + | +LL | struct Bar(std::marker::PhantomData); + | ------------- doesn't satisfy `Bar<_>: Deref` +... +LL | t.get(); + | ^^^ method cannot be called on `Rc>` due to unsatisfied trait bounds + | +note: the following trait bounds were not satisfied: + `<&Bar<_> as Deref>::Target = Bar<&Bar<_>>` + `<&Rc> as Deref>::Target = Bar<&Rc>>` + `<&mut Bar<_> as Deref>::Target = Bar<&mut Bar<_>>` + `<&mut Rc> as Deref>::Target = Bar<&mut Rc>>` + `> as Deref>::Target = Bar>>` + `Bar<_>: Deref` + --> $DIR/arbitrary-self-from-method-substs.rs:60:9 + | +LL | impl> Bar { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------ + | | | + | | unsatisfied trait bound introduced here + | unsatisfied trait bound introduced here +note: the trait `Deref` must be implemented + --> $SRC_DIR/core/src/ops/deref.rs:LL:COL + = help: items from traits can only be used if the trait is implemented and in scope + = note: the following trait defines an item `get`, perhaps you need to implement it: + candidate #1: `SliceIndex` + +error[E0599]: the method `get` exists for reference `&Rc>`, but its trait bounds were not satisfied + --> $DIR/arbitrary-self-from-method-substs.rs:108:7 + | +LL | struct Bar(std::marker::PhantomData); + | ------------- doesn't satisfy `Bar<_>: Deref` +... +LL | t.get(); + | ^^^ method cannot be called on `&Rc>` due to unsatisfied trait bounds + | +note: the following trait bounds were not satisfied: + `<&&Rc> as Deref>::Target = Bar<&&Rc>>` + `<&Bar<_> as Deref>::Target = Bar<&Bar<_>>` + `<&Rc> as Deref>::Target = Bar<&Rc>>` + `<&mut &Rc> as Deref>::Target = Bar<&mut &Rc>>` + `<&mut Bar<_> as Deref>::Target = Bar<&mut Bar<_>>` + `<&mut Rc> as Deref>::Target = Bar<&mut Rc>>` + `> as Deref>::Target = Bar>>` + `Bar<_>: Deref` + --> $DIR/arbitrary-self-from-method-substs.rs:60:9 + | +LL | impl> Bar { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ------ + | | | + | | unsatisfied trait bound introduced here + | unsatisfied trait bound introduced here +note: the trait `Deref` must be implemented + --> $SRC_DIR/core/src/ops/deref.rs:LL:COL + = help: items from traits can only be used if the trait is implemented and in scope + = note: the following trait defines an item `get`, perhaps you need to implement it: + candidate #1: `SliceIndex` + +error: aborting due to 14 previous errors + +Some errors have detailed explanations: E0271, E0308, E0599, E0801. +For more information about an error, try `rustc --explain E0271`. diff --git a/tests/ui/self/arbitrary-self-from-method-substs.rs b/tests/ui/self/arbitrary-self-from-method-substs.rs index 99977ed9b8c..f2d65859615 100644 --- a/tests/ui/self/arbitrary-self-from-method-substs.rs +++ b/tests/ui/self/arbitrary-self-from-method-substs.rs @@ -2,17 +2,109 @@ #![cfg_attr(feature, feature(arbitrary_self_types))] use std::ops::Deref; +use std::marker::PhantomData; struct Foo(u32); impl Foo { fn get>(self: R) -> u32 { - //[default]~^ ERROR: `R` cannot be used as the type of `self` + //~^ ERROR: invalid generic `self` parameter type self.0 } + fn get1>(self: &R) -> u32 { + //~^ ERROR: invalid generic `self` parameter type + self.0 + } + fn get2>(self: &mut R) -> u32 { + //~^ ERROR: invalid generic `self` parameter type + self.0 + } + fn get3>(self: std::rc::Rc) -> u32 { + //~^ ERROR: invalid generic `self` parameter type + self.0 + } + fn get4>(self: &std::rc::Rc) -> u32 { + //~^ ERROR: invalid generic `self` parameter type + self.0 + } + fn get5>(self: std::rc::Rc<&R>) -> u32 { + //~^ ERROR: invalid generic `self` parameter type + self.0 + } + fn get6(self: FR::Receiver, other: FR) -> u32 { + //[default]~^ ERROR: `::Receiver` cannot be used as the type of `self` + 42 + } +} + + +struct SmartPtr<'a, T: ?Sized>(&'a T); + +impl<'a, T: ?Sized> Deref for SmartPtr<'a, T> { + type Target = T; + fn deref(&self) -> &Self::Target { + unimplemented!() + } +} + +struct SmartPtr2<'a, T: ?Sized>(&'a T); + +impl<'a, T: ?Sized> Deref for SmartPtr2<'a, T> { + type Target = T; + fn deref(&self) -> &Self::Target { + unimplemented!() + } +} + +struct Bar(std::marker::PhantomData); + +impl> Bar { + fn get(self: R) {} + //[default]~^ ERROR: `R` cannot be used as the type of `self` +} + +trait FindReceiver { + type Receiver: Deref; +} + +struct Silly; +impl FindReceiver for Silly { + type Receiver = std::rc::Rc; } fn main() { let mut foo = Foo(1); foo.get::<&Foo>(); //[feature]~^ ERROR mismatched types + foo.get::>(); + //[feature]~^ ERROR mismatched types + + let smart_ptr = SmartPtr(&foo); + let smart_ptr2 = SmartPtr2(&foo); + smart_ptr.get(); // this compiles + smart_ptr.get::>(); + //[feature]~^ ERROR mismatched types + smart_ptr.get::<&Foo>(); + //[feature]~^ ERROR mismatched types + + let mut foo = Foo(1); + // This test is slightly contrived in an attempt to generate a mismatched types + // error for the self type below, without using the turbofish. + foo.get6(Silly); + //~^ ERROR type mismatch + let mut foo = Foo(1); + let foo = &foo; + foo.get6(Silly); + //~^ ERROR type mismatch + + let t = std::rc::Rc::new(Bar(std::marker::PhantomData)); + t.get(); + //~^ ERROR its trait bounds were not satisfied + let t = &t; + // This is a further attempt at triggering 'type mismatch' errors + // from arbitrary self types without resorting to the turbofish. + // Ideally, here, t is Thing> while we're going to call + // it with a &t method receiver. However, this doesn't work since that + // type of t becomes recursive and trait bounds can't be satisfied. + t.get(); + //~^ ERROR its trait bounds were not satisfied } diff --git a/tests/ui/type-alias-impl-trait/issue-57700.rs b/tests/ui/type-alias-impl-trait/issue-57700.rs deleted file mode 100644 index 8746545ecc9..00000000000 --- a/tests/ui/type-alias-impl-trait/issue-57700.rs +++ /dev/null @@ -1,21 +0,0 @@ -#![feature(arbitrary_self_types)] -#![feature(impl_trait_in_assoc_type)] - -use std::ops::Deref; - -trait Foo { - type Bar: Foo; - - fn foo(self: impl Deref) -> Self::Bar; -} - -impl Foo for C { - type Bar = impl Foo; - - fn foo(self: impl Deref) -> Self::Bar { - self - //~^ Error type parameter `impl Deref` is part of concrete type but not used in parameter list for the `impl Trait` type alias - } -} - -fn main() {} diff --git a/tests/ui/type-alias-impl-trait/issue-57700.stderr b/tests/ui/type-alias-impl-trait/issue-57700.stderr deleted file mode 100644 index 7efb05f40b0..00000000000 --- a/tests/ui/type-alias-impl-trait/issue-57700.stderr +++ /dev/null @@ -1,8 +0,0 @@ -error: type parameter `impl Deref` is part of concrete type but not used in parameter list for the `impl Trait` type alias - --> $DIR/issue-57700.rs:16:9 - | -LL | self - | ^^^^ - -error: aborting due to 1 previous error -