From 00da9fc961e9b7b369a950c71d88126bbefc677c Mon Sep 17 00:00:00 2001
From: Georg Semmler <github@weiznich.de>
Date: Sat, 20 Jul 2024 16:45:33 +0200
Subject: [PATCH] Start using `#[diagnostic::do_not_recommend]` in the standard
library
This commit starts using `#[diagnostic::do_not_recommend]` in the
standard library to improve some error messages. In this case we just
hide a certain nightly only impl as suggested in #121521
---
library/core/src/lib.rs | 1 +
library/core/src/option.rs | 1 +
library/core/src/result.rs | 2 +-
tests/ui/try-trait/bad-interconversion.stderr | 16 ++++------------
tests/ui/try-trait/option-to-result.stderr | 8 ++------
tests/ui/try-trait/try-on-option.stderr | 4 +---
6 files changed, 10 insertions(+), 22 deletions(-)
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 49f89e70255..02cb02dce1d 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -165,6 +165,7 @@
#![feature(const_unsafecell_get_mut)]
#![feature(const_waker)]
#![feature(coverage_attribute)]
+#![feature(do_not_recommend)]
#![feature(duration_consts_float)]
#![feature(internal_impls_macro)]
#![feature(ip)]
diff --git a/library/core/src/option.rs b/library/core/src/option.rs
index 1a8fe1e6051..d93cb8d10e6 100644
--- a/library/core/src/option.rs
+++ b/library/core/src/option.rs
@@ -2507,6 +2507,7 @@ impl<T> ops::FromResidual for Option<T> {
}
}
+#[diagnostic::do_not_recommend]
#[unstable(feature = "try_trait_v2_yeet", issue = "96374")]
impl<T> ops::FromResidual<ops::Yeet<()>> for Option<T> {
#[inline]
diff --git a/library/core/src/result.rs b/library/core/src/result.rs
index f8cdcc000c5..7f278296b7b 100644
--- a/library/core/src/result.rs
+++ b/library/core/src/result.rs
@@ -1990,7 +1990,7 @@ impl<T, E, F: From<E>> ops::FromResidual<Result<convert::Infallible, E>> for Res
}
}
}
-
+#[diagnostic::do_not_recommend]
#[unstable(feature = "try_trait_v2_yeet", issue = "96374")]
impl<T, E, F: From<E>> ops::FromResidual<ops::Yeet<E>> for Result<T, F> {
#[inline]
diff --git a/tests/ui/try-trait/bad-interconversion.stderr b/tests/ui/try-trait/bad-interconversion.stderr
index c30b6334fed..642a93d64e2 100644
--- a/tests/ui/try-trait/bad-interconversion.stderr
+++ b/tests/ui/try-trait/bad-interconversion.stderr
@@ -23,9 +23,7 @@ LL | Some(3)?;
| ^ use `.ok_or(...)?` to provide an error compatible with `Result<u64, String>`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<u64, String>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Result<T, F>` implements `FromResidual<Result<Infallible, E>>`
- `Result<T, F>` implements `FromResidual<Yeet<E>>`
+ = help: the trait `FromResidual<Result<Infallible, E>>` is implemented for `Result<T, F>`
error[E0277]: the `?` operator can only be used on `Result`s in a function that returns `Result`
--> $DIR/bad-interconversion.rs:17:31
@@ -36,9 +34,7 @@ LL | Ok(ControlFlow::Break(123)?)
| ^ this `?` produces `ControlFlow<{integer}, Infallible>`, which is incompatible with `Result<u64, String>`
|
= help: the trait `FromResidual<ControlFlow<{integer}, Infallible>>` is not implemented for `Result<u64, String>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Result<T, F>` implements `FromResidual<Result<Infallible, E>>`
- `Result<T, F>` implements `FromResidual<Yeet<E>>`
+ = help: the trait `FromResidual<Result<Infallible, E>>` is implemented for `Result<T, F>`
error[E0277]: the `?` operator can only be used on `Option`s, not `Result`s, in a function that returns `Option`
--> $DIR/bad-interconversion.rs:22:22
@@ -49,9 +45,7 @@ LL | Some(Err("hello")?)
| ^ use `.ok()?` if you want to discard the `Result<Infallible, &str>` error information
|
= help: the trait `FromResidual<Result<Infallible, &str>>` is not implemented for `Option<u16>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Option<T>` implements `FromResidual<Yeet<()>>`
- `Option<T>` implements `FromResidual`
+ = help: the trait `FromResidual` is implemented for `Option<T>`
error[E0277]: the `?` operator can only be used on `Option`s in a function that returns `Option`
--> $DIR/bad-interconversion.rs:27:33
@@ -62,9 +56,7 @@ LL | Some(ControlFlow::Break(123)?)
| ^ this `?` produces `ControlFlow<{integer}, Infallible>`, which is incompatible with `Option<u64>`
|
= help: the trait `FromResidual<ControlFlow<{integer}, Infallible>>` is not implemented for `Option<u64>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Option<T>` implements `FromResidual<Yeet<()>>`
- `Option<T>` implements `FromResidual`
+ = help: the trait `FromResidual` is implemented for `Option<T>`
error[E0277]: the `?` operator can only be used on `ControlFlow`s in a function that returns `ControlFlow`
--> $DIR/bad-interconversion.rs:32:39
diff --git a/tests/ui/try-trait/option-to-result.stderr b/tests/ui/try-trait/option-to-result.stderr
index 2d97226275d..8055b2a0b04 100644
--- a/tests/ui/try-trait/option-to-result.stderr
+++ b/tests/ui/try-trait/option-to-result.stderr
@@ -8,9 +8,7 @@ LL | a?;
| ^ use `.ok_or(...)?` to provide an error compatible with `Result<(), ()>`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<(), ()>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Result<T, F>` implements `FromResidual<Result<Infallible, E>>`
- `Result<T, F>` implements `FromResidual<Yeet<E>>`
+ = help: the trait `FromResidual<Result<Infallible, E>>` is implemented for `Result<T, F>`
error[E0277]: the `?` operator can only be used on `Option`s, not `Result`s, in a function that returns `Option`
--> $DIR/option-to-result.rs:11:6
@@ -22,9 +20,7 @@ LL | a?;
| ^ use `.ok()?` if you want to discard the `Result<Infallible, i32>` error information
|
= help: the trait `FromResidual<Result<Infallible, i32>>` is not implemented for `Option<i32>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Option<T>` implements `FromResidual<Yeet<()>>`
- `Option<T>` implements `FromResidual`
+ = help: the trait `FromResidual` is implemented for `Option<T>`
error: aborting due to 2 previous errors
diff --git a/tests/ui/try-trait/try-on-option.stderr b/tests/ui/try-trait/try-on-option.stderr
index 84a51a078af..15d0b28ddc1 100644
--- a/tests/ui/try-trait/try-on-option.stderr
+++ b/tests/ui/try-trait/try-on-option.stderr
@@ -8,9 +8,7 @@ LL | x?;
| ^ use `.ok_or(...)?` to provide an error compatible with `Result<u32, ()>`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<u32, ()>`
- = help: the following other types implement trait `FromResidual<R>`:
- `Result<T, F>` implements `FromResidual<Result<Infallible, E>>`
- `Result<T, F>` implements `FromResidual<Yeet<E>>`
+ = help: the trait `FromResidual<Result<Infallible, E>>` is implemented for `Result<T, F>`
error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/try-on-option.rs:11:6