Rollup merge of rust-lang#96516 - oli-obk:impl_trait_inference_accide…

…ntal_permitted, r=jackh726 Revert diagnostic duplication and accidental stabilization fixes rust-lang#96460 this is an accidental stabilization that we should put into the beta. I believe it is low-risk, because it was literally what we had before rust-lang#94081 The effect on tests is massive, but mostly deduplication of diagnostics and some minor span changes.
esp-rs · May 17, 2022 · 2ef5103 · 2ef5103
1 parent a7fcff3
commit 2ef5103
Show file tree

Hide file tree

Showing 44 changed files with 97 additions and 384 deletions.
diff --git a/compiler/rustc_typeck/src/check/check.rs b/compiler/rustc_typeck/src/check/check.rs
@@ -102,6 +102,12 @@ pub(super) fn check_fn<'a, 'tcx>(
  DUMMY_SP,
  param_env,
  ));
+ // HACK(oli-obk): we rewrite the declared return type, too, so that we don't end up inferring all
+ // unconstrained RPIT to have `()` as their hidden type. This would happen because further down we
+ // compare the ret_coercion with declared_ret_ty, and anything uninferred would be inferred to the
+ // opaque type itself. That again would cause writeback to assume we have a recursive call site
+ // and do the sadly stabilized fallback to `()`.
+ let declared_ret_ty = ret_ty;
  fcx.ret_coercion = Some(RefCell::new(CoerceMany::new(ret_ty)));
  fcx.ret_type_span = Some(decl.output.span());
 

diff --git a/src/test/ui/associated-types/impl-trait-return-missing-constraint.rs b/src/test/ui/associated-types/impl-trait-return-missing-constraint.rs
@@ -24,7 +24,6 @@ fn bar() -> impl Bar {
 
 fn baz() -> impl Bar<Item = i32> {
  //~^ ERROR type mismatch resolving `<impl Bar as Foo>::Item == i32`
- //~| ERROR type mismatch resolving `<impl Bar as Foo>::Item == i32`
  bar()
 }
 

diff --git a/src/test/ui/associated-types/impl-trait-return-missing-constraint.stderr b/src/test/ui/associated-types/impl-trait-return-missing-constraint.stderr
@@ -16,29 +16,6 @@ help: consider constraining the associated type `<impl Bar as Foo>::Item` to `i3
 LL | fn bar() -> impl Bar<Item = i32> {
  | ++++++++++++
 
-error[E0271]: type mismatch resolving `<impl Bar as Foo>::Item == i32`
- --> $DIR/impl-trait-return-missing-constraint.rs:25:34
- |
-LL | fn bar() -> impl Bar {
- | -------- the expected opaque type
-...
-LL | fn baz() -> impl Bar<Item = i32> {
- | __________________________________^
-LL | |
-LL | |
-LL | | bar()
-LL | | }
- | |_^ expected associated type, found `i32`
- |
- = note: expected associated type `<impl Bar as Foo>::Item`
- found type `i32`
- = help: consider constraining the associated type `<impl Bar as Foo>::Item` to `i32` or calling a method that returns `<impl Bar as Foo>::Item`
- = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
-help: consider constraining the associated type `<impl Bar as Foo>::Item` to `i32`
- |
-LL | fn bar() -> impl Bar<Item = i32> {
- | ++++++++++++
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0271`.
diff --git a/src/test/ui/conservative_impl_trait.rs b/src/test/ui/conservative_impl_trait.rs
@@ -2,7 +2,6 @@
 
 fn will_ice(something: &u32) -> impl Iterator<Item = &u32> {
  //~^ ERROR `()` is not an iterator
- //~| ERROR `()` is not an iterator
 }
 
 fn main() {}
diff --git a/src/test/ui/conservative_impl_trait.stderr b/src/test/ui/conservative_impl_trait.stderr
@@ -6,18 +6,6 @@ LL | fn will_ice(something: &u32) -> impl Iterator<Item = &u32> {
  |
  = help: the trait `Iterator` is not implemented for `()`
 
-error[E0277]: `()` is not an iterator
- --> $DIR/conservative_impl_trait.rs:3:60
- |
-LL | fn will_ice(something: &u32) -> impl Iterator<Item = &u32> {
- | ____________________________________________________________^
-LL | |
-LL | |
-LL | | }
- | |_^ `()` is not an iterator
- |
- = help: the trait `Iterator` is not implemented for `()`
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/const-generics/defaults/rp_impl_trait_fail.rs b/src/test/ui/const-generics/defaults/rp_impl_trait_fail.rs
@@ -5,7 +5,6 @@ impl<const N: u32> Trait for Uwu<N> {}
 
 fn rawr() -> impl Trait {
  //~^ error: the trait bound `Uwu<10_u32, 12_u32>: Trait` is not satisfied
- //~| error: the trait bound `Uwu<10_u32, 12_u32>: Trait` is not satisfied
  Uwu::<10, 12>
 }
 
@@ -17,13 +16,11 @@ impl Traitor<1, 2> for u64 {}
 
 fn uwu<const N: u8>() -> impl Traitor<N> {
  //~^ error: the trait bound `u32: Traitor<N, N>` is not satisfied
- //~| error: the trait bound `u32: Traitor<N, N>` is not satisfied
  1_u32
 }
 
 fn owo() -> impl Traitor {
  //~^ error: the trait bound `u64: Traitor<1_u8, 1_u8>` is not satisfied
- //~| error: the trait bound `u64: Traitor<1_u8, 1_u8>` is not satisfied
  1_u64
 }
 

diff --git a/src/test/ui/const-generics/defaults/rp_impl_trait_fail.stderr b/src/test/ui/const-generics/defaults/rp_impl_trait_fail.stderr
@@ -7,22 +7,8 @@ LL | fn rawr() -> impl Trait {
  = help: the following implementations were found:
  <Uwu<N> as Trait>
 
-error[E0277]: the trait bound `Uwu<10_u32, 12_u32>: Trait` is not satisfied
- --> $DIR/rp_impl_trait_fail.rs:6:25
- |
-LL | fn rawr() -> impl Trait {
- | _________________________^
-LL | |
-LL | |
-LL | | Uwu::<10, 12>
-LL | | }
- | |_^ the trait `Trait` is not implemented for `Uwu<10_u32, 12_u32>`
- |
- = help: the following implementations were found:
- <Uwu<N> as Trait>
-
 error[E0277]: the trait bound `u32: Traitor<N, N>` is not satisfied
- --> $DIR/rp_impl_trait_fail.rs:18:26
+ --> $DIR/rp_impl_trait_fail.rs:17:26
  |
 LL | fn uwu<const N: u8>() -> impl Traitor<N> {
  | ^^^^^^^^^^^^^^^ the trait `Traitor<N, N>` is not implemented for `u32`
@@ -31,23 +17,8 @@ LL | fn uwu<const N: u8>() -> impl Traitor<N> {
  <u32 as Traitor<N, 2_u8>>
  <u64 as Traitor<1_u8, 2_u8>>
 
-error[E0277]: the trait bound `u32: Traitor<N, N>` is not satisfied
- --> $DIR/rp_impl_trait_fail.rs:18:42
- |
-LL | fn uwu<const N: u8>() -> impl Traitor<N> {
- | __________________________________________^
-LL | |
-LL | |
-LL | | 1_u32
-LL | | }
- | |_^ the trait `Traitor<N, N>` is not implemented for `u32`
- |
- = help: the following implementations were found:
- <u32 as Traitor<N, 2_u8>>
- <u64 as Traitor<1_u8, 2_u8>>
-
 error[E0277]: the trait bound `u64: Traitor<1_u8, 1_u8>` is not satisfied
- --> $DIR/rp_impl_trait_fail.rs:24:13
+ --> $DIR/rp_impl_trait_fail.rs:22:13
  |
 LL | fn owo() -> impl Traitor {
  | ^^^^^^^^^^^^ the trait `Traitor<1_u8, 1_u8>` is not implemented for `u64`
@@ -56,21 +27,6 @@ LL | fn owo() -> impl Traitor {
  <u64 as Traitor<1_u8, 2_u8>>
  <u32 as Traitor<N, 2_u8>>
 
-error[E0277]: the trait bound `u64: Traitor<1_u8, 1_u8>` is not satisfied
- --> $DIR/rp_impl_trait_fail.rs:24:26
- |
-LL | fn owo() -> impl Traitor {
- | __________________________^
-LL | |
-LL | |
-LL | | 1_u64
-LL | | }
- | |_^ the trait `Traitor<1_u8, 1_u8>` is not implemented for `u64`
- |
- = help: the following implementations were found:
- <u64 as Traitor<1_u8, 2_u8>>
- <u32 as Traitor<N, 2_u8>>
-
-error: aborting due to 6 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/generator/issue-88653.rs b/src/test/ui/generator/issue-88653.rs
@@ -7,13 +7,10 @@ use std::ops::Generator;
 
 fn foo(bar: bool) -> impl Generator<(bool,)> {
  //~^ ERROR: type mismatch in generator arguments [E0631]
- //~| ERROR: type mismatch in generator arguments [E0631]
- //~| NOTE: expected signature of `fn((bool,)) -> _`
  //~| NOTE: expected signature of `fn((bool,)) -> _`
  //~| NOTE: in this expansion of desugaring of `impl Trait`
  |bar| {
  //~^ NOTE: found signature of `fn(bool) -> _`
- //~| NOTE: found signature of `fn(bool) -> _`
  if bar {
  yield bar;
  }

diff --git a/src/test/ui/generator/issue-88653.stderr b/src/test/ui/generator/issue-88653.stderr
@@ -7,22 +7,6 @@ LL | fn foo(bar: bool) -> impl Generator<(bool,)> {
 LL | |bar| {
  | ----- found signature of `fn(bool) -> _`
 
-error[E0631]: type mismatch in generator arguments
- --> $DIR/issue-88653.rs:8:46
- |
-LL | fn foo(bar: bool) -> impl Generator<(bool,)> {
- | ______________________________________________^
-LL | |
-LL | |
-LL | |
-... |
-LL | | |bar| {
- | | ----- found signature of `fn(bool) -> _`
-... |
-LL | | }
-LL | | }
- | |_^ expected signature of `fn((bool,)) -> _`
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0631`.
diff --git a/src/test/ui/generator/type-mismatch-signature-deduction.rs b/src/test/ui/generator/type-mismatch-signature-deduction.rs
@@ -4,7 +4,6 @@ use std::ops::Generator;
 
 fn foo() -> impl Generator<Return = i32> {
  //~^ ERROR type mismatch
- //~| ERROR type mismatch
  || {
  if false {
  return Ok(6);

diff --git a/src/test/ui/generator/type-mismatch-signature-deduction.stderr b/src/test/ui/generator/type-mismatch-signature-deduction.stderr
@@ -1,18 +1,18 @@
 error[E0308]: mismatched types
- --> $DIR/type-mismatch-signature-deduction.rs:15:9
+ --> $DIR/type-mismatch-signature-deduction.rs:14:9
  |
 LL | 5
  | ^ expected enum `Result`, found integer
  |
  = note: expected type `Result<{integer}, _>`
  found type `{integer}`
 note: return type inferred to be `Result<{integer}, _>` here
- --> $DIR/type-mismatch-signature-deduction.rs:10:20
+ --> $DIR/type-mismatch-signature-deduction.rs:9:20
  |
 LL | return Ok(6);
  | ^^^^^
 
-error[E0271]: type mismatch resolving `<[generator@$DIR/type-mismatch-signature-deduction.rs:8:5: 16:6] as Generator>::Return == i32`
+error[E0271]: type mismatch resolving `<[generator@$DIR/type-mismatch-signature-deduction.rs:7:5: 15:6] as Generator>::Return == i32`
  --> $DIR/type-mismatch-signature-deduction.rs:5:13
  |
 LL | fn foo() -> impl Generator<Return = i32> {
@@ -21,23 +21,7 @@ LL | fn foo() -> impl Generator<Return = i32> {
  = note: expected enum `Result<{integer}, _>`
  found type `i32`
 
-error[E0271]: type mismatch resolving `<[generator@$DIR/type-mismatch-signature-deduction.rs:8:5: 16:6] as Generator>::Return == i32`
- --> $DIR/type-mismatch-signature-deduction.rs:5:42
- |
-LL | fn foo() -> impl Generator<Return = i32> {
- | __________________________________________^
-LL | |
-LL | |
-LL | | || {
-... |
-LL | | }
-LL | | }
- | |_^ expected enum `Result`, found `i32`
- |
- = note: expected enum `Result<{integer}, _>`
- found type `i32`
-
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
 Some errors have detailed explanations: E0271, E0308.
 For more information about an error, try `rustc --explain E0271`.
diff --git a/src/test/ui/impl-trait/bound-normalization-fail.rs b/src/test/ui/impl-trait/bound-normalization-fail.rs
@@ -24,7 +24,6 @@ mod impl_trait {
  /// `T::Assoc` can't be normalized any further here.
  fn foo_fail<T: Trait>() -> impl FooLike<Output = T::Assoc> {
  //~^ ERROR: type mismatch
- //~| ERROR: type mismatch
  Foo(())
  }
 }
@@ -42,7 +41,6 @@ mod lifetimes {
  fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
  //~^ ERROR `impl Trait` return type cannot contain a projection or `Self` that references lifetimes from a parent scope
  //~| ERROR: type mismatch
- //~| ERROR: type mismatch
  Foo(())
  }
 }

diff --git a/src/test/ui/impl-trait/bound-normalization-fail.stderr b/src/test/ui/impl-trait/bound-normalization-fail.stderr
@@ -16,37 +16,14 @@ help: consider constraining the associated type `<T as impl_trait::Trait>::Assoc
 LL | fn foo_fail<T: Trait<Assoc = ()>>() -> impl FooLike<Output = T::Assoc> {
  | ++++++++++++
 
-error[E0271]: type mismatch resolving `<Foo<()> as FooLike>::Output == <T as impl_trait::Trait>::Assoc`
- --> $DIR/bound-normalization-fail.rs:25:64
- |
-LL | fn foo_fail<T: Trait>() -> impl FooLike<Output = T::Assoc> {
- | ________________________________________________________________^
-LL | |
-LL | |
-LL | | Foo(())
-LL | | }
- | |_____^ type mismatch resolving `<Foo<()> as FooLike>::Output == <T as impl_trait::Trait>::Assoc`
- |
-note: expected this to be `()`
- --> $DIR/bound-normalization-fail.rs:14:19
- |
-LL | type Output = T;
- | ^
- = note: expected unit type `()`
- found associated type `<T as impl_trait::Trait>::Assoc`
-help: consider constraining the associated type `<T as impl_trait::Trait>::Assoc` to `()`
- |
-LL | fn foo_fail<T: Trait<Assoc = ()>>() -> impl FooLike<Output = T::Assoc> {
- | ++++++++++++
-
 error[E0760]: `impl Trait` return type cannot contain a projection or `Self` that references lifetimes from a parent scope
- --> $DIR/bound-normalization-fail.rs:42:41
+ --> $DIR/bound-normalization-fail.rs:41:41
  |
 LL | fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0271]: type mismatch resolving `<Foo<()> as FooLike>::Output == <T as lifetimes::Trait<'static>>::Assoc`
- --> $DIR/bound-normalization-fail.rs:42:41
+ --> $DIR/bound-normalization-fail.rs:41:41
  |
 LL | fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type mismatch resolving `<Foo<()> as FooLike>::Output == <T as lifetimes::Trait<'static>>::Assoc`
@@ -63,31 +40,7 @@ help: consider constraining the associated type `<T as lifetimes::Trait<'static>
 LL | fn foo2_fail<'a, T: Trait<'a, Assoc = ()>>() -> impl FooLike<Output = T::Assoc> {
  | ++++++++++++
 
-error[E0271]: type mismatch resolving `<Foo<()> as FooLike>::Output == <T as lifetimes::Trait<'static>>::Assoc`
- --> $DIR/bound-normalization-fail.rs:42:73
- |
-LL | fn foo2_fail<'a, T: Trait<'a>>() -> impl FooLike<Output = T::Assoc> {
- | _________________________________________________________________________^
-LL | |
-LL | |
-LL | |
-LL | | Foo(())
-LL | | }
- | |_____^ type mismatch resolving `<Foo<()> as FooLike>::Output == <T as lifetimes::Trait<'static>>::Assoc`
- |
-note: expected this to be `()`
- --> $DIR/bound-normalization-fail.rs:14:19
- |
-LL | type Output = T;
- | ^
- = note: expected unit type `()`
- found associated type `<T as lifetimes::Trait<'static>>::Assoc`
-help: consider constraining the associated type `<T as lifetimes::Trait<'static>>::Assoc` to `()`
- |
-LL | fn foo2_fail<'a, T: Trait<'a, Assoc = ()>>() -> impl FooLike<Output = T::Assoc> {
- | ++++++++++++
-
-error: aborting due to 5 previous errors
+error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0271, E0760.
 For more information about an error, try `rustc --explain E0271`.
diff --git a/src/test/ui/impl-trait/cross-return-site-inference.rs b/src/test/ui/impl-trait/cross-return-site-inference.rs
@@ -29,17 +29,17 @@ fn baa(b: bool) -> impl std::fmt::Debug {
 }
 
 fn muh() -> Result<(), impl std::fmt::Debug> {
- Err("whoops")?; //~ ERROR `?` couldn't convert the error to `impl Debug`
+ Err("whoops")?; //~^ ERROR type annotations needed
  Ok(())
 }
 
 fn muh2() -> Result<(), impl std::fmt::Debug> {
- return Err(From::from("foo")); //~ ERROR the trait bound `impl Debug: From<&str>` is not satisfied
+ return Err(From::from("foo")); //~^ ERROR type annotations needed
  Ok(())
 }
 
 fn muh3() -> Result<(), impl std::fmt::Debug> {
- Err(From::from("foo")) //~ ERROR the trait bound `impl Debug: From<&str>` is not satisfied
+ Err(From::from("foo")) //~^ ERROR type annotations needed
 }
 
 fn main() {}