clean up some old const trait impl syntax

[npmccallum]

Related to: #143874

[rustbot]

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[rustbot]

rust-analyzer is developed in its own repository. If possible, consider making this change to rust-lang/rust-analyzer instead.

cc @rust-lang/rust-analyzer

Some changes occurred to the intrinsics. Make sure the CTFE / Miri interpreter
gets adapted for the changes, if necessary.

cc @rust-lang/miri, @RalfJung, @oli-obk, @lcnr

[zachs18]

I think these two lines need to be flipped in rustfmt, so it formats the visibility of a trait before the constness.

rust/src/tools/rustfmt/src/items.rs

Lines 1178 to 1179 in 828e45a

	format_constness(constness),
	format_visibility(context, &item.vis),

Also, I think the tidy checks use bootstrap~~/beta~~ rustfmt, not in-tree rustfmt, so fixing rustfmt will probably need to happen first, then the stdlib changes will probably be blocked on the rustfmt fix reaching beta.

[bjorn3]

We use a pinned nightly for rustfmt, so landing a rustfmt change and updating rustfmt the next day should work.

[npmccallum]

It seems that this:

rust/src/tools/rustfmt/src/items.rs

Lines 1176 to 1182 in 84a1747

	let header = format!(
	"{}{}{}{}trait ",
	format_constness(constness),
	format_visibility(context, &item.vis),
	format_safety(safety),
	format_auto(is_auto),
	);

Conflicts with:

https://github.com/rust-lang/rustfmt/blob/0332da01486508710f2a542111e40513bfb215aa/src/items.rs#L1169-L1174

[rustbot]

Some changes occurred in src/tools/rustfmt

cc @rust-lang/rustfmt

[bors]

☔ The latest upstream changes (presumably #146160) made this pull request unmergeable. Please resolve the merge conflicts.

[rustbot]

This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[rust-log-analyzer]

The job tidy failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

     #[rustc_diagnostic_item = "deref_target"]
Diff in /checkout/library/core/src/ops/deref.rs:267:
 #[doc(alias = "*")]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-pub const trait DerefMut: [const] Deref + PointeeSized {
+const pub trait DerefMut: [const] Deref + PointeeSized {
     /// Mutably dereferences the value.
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_diagnostic_item = "deref_mut_method"]
Diff in /checkout/library/core/src/ops/bit.rs:32:
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_ops", issue = "143802")]
 #[doc(alias = "!")]
-pub const trait Not {
+const pub trait Not {
     /// The resulting type after applying the `!` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/bit.rs:147:
     message = "no implementation for `{Self} & {Rhs}`",
     label = "no implementation for `{Self} & {Rhs}`"
 )]
-pub const trait BitAnd<Rhs = Self> {
+const pub trait BitAnd<Rhs = Self> {
     /// The resulting type after applying the `&` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/bit.rs:251:
     message = "no implementation for `{Self} | {Rhs}`",
     label = "no implementation for `{Self} | {Rhs}`"
 )]
-pub const trait BitOr<Rhs = Self> {
+const pub trait BitOr<Rhs = Self> {
     /// The resulting type after applying the `|` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/bit.rs:355:
     message = "no implementation for `{Self} ^ {Rhs}`",
     label = "no implementation for `{Self} ^ {Rhs}`"
 )]
-pub const trait BitXor<Rhs = Self> {
+const pub trait BitXor<Rhs = Self> {
     /// The resulting type after applying the `^` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/bit.rs:458:
     message = "no implementation for `{Self} << {Rhs}`",
     label = "no implementation for `{Self} << {Rhs}`"
 )]
-pub const trait Shl<Rhs = Self> {
+const pub trait Shl<Rhs = Self> {
     /// The resulting type after applying the `<<` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/bit.rs:580:
     message = "no implementation for `{Self} >> {Rhs}`",
     label = "no implementation for `{Self} >> {Rhs}`"
 )]
-pub const trait Shr<Rhs = Self> {
+const pub trait Shr<Rhs = Self> {
     /// The resulting type after applying the `>>` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/bit.rs:711:
     message = "no implementation for `{Self} &= {Rhs}`",
     label = "no implementation for `{Self} &= {Rhs}`"
 )]
-pub const trait BitAndAssign<Rhs = Self> {
+const pub trait BitAndAssign<Rhs = Self> {
     /// Performs the `&=` operation.
     ///
     /// # Examples
Diff in /checkout/library/core/src/ops/bit.rs:786:
     message = "no implementation for `{Self} |= {Rhs}`",
     label = "no implementation for `{Self} |= {Rhs}`"
 )]
-pub const trait BitOrAssign<Rhs = Self> {
+const pub trait BitOrAssign<Rhs = Self> {
     /// Performs the `|=` operation.
     ///
     /// # Examples
Diff in /checkout/library/core/src/ops/bit.rs:861:
     message = "no implementation for `{Self} ^= {Rhs}`",
     label = "no implementation for `{Self} ^= {Rhs}`"
 )]
-pub const trait BitXorAssign<Rhs = Self> {
+const pub trait BitXorAssign<Rhs = Self> {
     /// Performs the `^=` operation.
     ///
     /// # Examples
Diff in /checkout/library/core/src/ops/bit.rs:934:
     message = "no implementation for `{Self} <<= {Rhs}`",
     label = "no implementation for `{Self} <<= {Rhs}`"
 )]
-pub const trait ShlAssign<Rhs = Self> {
+const pub trait ShlAssign<Rhs = Self> {
     /// Performs the `<<=` operation.
     ///
     /// # Examples
Diff in /checkout/library/core/src/ops/bit.rs:1020:
     message = "no implementation for `{Self} >>= {Rhs}`",
     label = "no implementation for `{Self} >>= {Rhs}`"
 )]
-pub const trait ShrAssign<Rhs = Self> {
+const pub trait ShrAssign<Rhs = Self> {
     /// Performs the `>>=` operation.
     ///
     /// # Examples
Diff in /checkout/library/core/src/ops/function.rs:73:
 #[fundamental] // so that regex can rely that `&str: !FnMut`
 #[must_use = "closures are lazy and do nothing unless called"]
 #[rustc_const_unstable(feature = "const_trait_impl", issue = "143874")]
-pub const trait Fn<Args: Tuple>: FnMut<Args> {
+const pub trait Fn<Args: Tuple>: FnMut<Args> {
     /// Performs the call operation.
     #[unstable(feature = "fn_traits", issue = "29625")]
     extern "rust-call" fn call(&self, args: Args) -> Self::Output;
Diff in /checkout/library/core/src/ops/function.rs:160:
 #[fundamental] // so that regex can rely that `&str: !FnMut`
 #[must_use = "closures are lazy and do nothing unless called"]
 #[rustc_const_unstable(feature = "const_trait_impl", issue = "143874")]
-pub const trait FnMut<Args: Tuple>: FnOnce<Args> {
+const pub trait FnMut<Args: Tuple>: FnOnce<Args> {
     /// Performs the call operation.
     #[unstable(feature = "fn_traits", issue = "29625")]
     extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
Diff in /checkout/library/core/src/ops/function.rs:239:
 #[fundamental] // so that regex can rely that `&str: !FnMut`
 #[must_use = "closures are lazy and do nothing unless called"]
 #[rustc_const_unstable(feature = "const_trait_impl", issue = "143874")]
-pub const trait FnOnce<Args: Tuple> {
+const pub trait FnOnce<Args: Tuple> {
     /// The returned type after the call operator is used.
     #[lang = "fn_once_output"]
     #[stable(feature = "fn_once_output", since = "1.12.0")]
Diff in /checkout/library/core/src/ops/index.rs:56:
 #[doc(alias = "[")]
 #[doc(alias = "[]")]
 #[rustc_const_unstable(feature = "const_index", issue = "143775")]
-pub const trait Index<Idx: ?Sized> {
+const pub trait Index<Idx: ?Sized> {
     /// The returned type after indexing.
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_diagnostic_item = "IndexOutput"]
Diff in /checkout/library/core/src/ops/index.rs:167:
 #[doc(alias = "]")]
 #[doc(alias = "[]")]
 #[rustc_const_unstable(feature = "const_index", issue = "143775")]
-pub const trait IndexMut<Idx: ?Sized>: [const] Index<Idx> {
+const pub trait IndexMut<Idx: ?Sized>: [const] Index<Idx> {
     /// Performs the mutable indexing (`container[index]`) operation.
     ///
     /// # Panics
Diff in /checkout/library/core/src/ops/drop.rs:204:
 #[lang = "drop"]
 #[stable(feature = "rust1", since = "1.0.0")]
---
     type Output;
Diff in /checkout/library/core/src/ops/arith.rs:187:
     append_const_msg
 )]
 #[doc(alias = "-")]
-pub const trait Sub<Rhs = Self> {
+const pub trait Sub<Rhs = Self> {
     /// The resulting type after applying the `-` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/arith.rs:321:
     label = "no implementation for `{Self} * {Rhs}`"
 )]
 #[doc(alias = "*")]
-pub const trait Mul<Rhs = Self> {
+const pub trait Mul<Rhs = Self> {
     /// The resulting type after applying the `*` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/arith.rs:459:
     label = "no implementation for `{Self} / {Rhs}`"
 )]
 #[doc(alias = "/")]
-pub const trait Div<Rhs = Self> {
+const pub trait Div<Rhs = Self> {
     /// The resulting type after applying the `/` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/arith.rs:568:
     label = "no implementation for `{Self} % {Rhs}`"
 )]
 #[doc(alias = "%")]
-pub const trait Rem<Rhs = Self> {
+const pub trait Rem<Rhs = Self> {
     /// The resulting type after applying the `%` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/arith.rs:689:
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_ops", issue = "143802")]
---
     #[stable(feature = "rust1", since = "1.0.0")]
     type Output;
Diff in /checkout/library/core/src/ops/arith.rs:766:
 )]
 #[doc(alias = "+")]
 #[doc(alias = "+=")]
-pub const trait AddAssign<Rhs = Self> {
+const pub trait AddAssign<Rhs = Self> {
     /// Performs the `+=` operation.
     ///
     /// # Example
Diff in /checkout/library/core/src/ops/arith.rs:837:
 )]
 #[doc(alias = "-")]
 #[doc(alias = "-=")]
-pub const trait SubAssign<Rhs = Self> {
+const pub trait SubAssign<Rhs = Self> {
     /// Performs the `-=` operation.
     ///
     /// # Example
Diff in /checkout/library/core/src/ops/arith.rs:899:
 )]
 #[doc(alias = "*")]
 #[doc(alias = "*=")]
-pub const trait MulAssign<Rhs = Self> {
+const pub trait MulAssign<Rhs = Self> {
     /// Performs the `*=` operation.
     ///
     /// # Example
Diff in /checkout/library/core/src/ops/arith.rs:961:
 )]
 #[doc(alias = "/")]
 #[doc(alias = "/=")]
-pub const trait DivAssign<Rhs = Self> {
+const pub trait DivAssign<Rhs = Self> {
     /// Performs the `/=` operation.
     ///
     /// # Example
Diff in /checkout/library/core/src/ops/arith.rs:1026:
 )]
 #[doc(alias = "%")]
 #[doc(alias = "%=")]
-pub const trait RemAssign<Rhs = Self> {
+const pub trait RemAssign<Rhs = Self> {
     /// Performs the `%=` operation.
     ///
     /// # Example
Diff in /checkout/library/core/src/ops/try_trait.rs:129:
 #[doc(alias = "?")]
 #[lang = "Try"]
 #[rustc_const_unstable(feature = "const_try", issue = "74935")]
-pub const trait Try: [const] FromResidual {
+const pub trait Try: [const] FromResidual {
     /// The type of the value produced by `?` when *not* short-circuiting.
     #[unstable(feature = "try_trait_v2", issue = "84277", old_name = "try_trait")]
     type Output;
Diff in /checkout/library/core/src/ops/try_trait.rs:306:
 #[rustc_diagnostic_item = "FromResidual"]
 #[unstable(feature = "try_trait_v2", issue = "84277", old_name = "try_trait")]
 #[rustc_const_unstable(feature = "const_try", issue = "74935")]
-pub const trait FromResidual<R = <Self as Try>::Residual> {
+const pub trait FromResidual<R = <Self as Try>::Residual> {
     /// Constructs the type from a compatible `Residual` type.
     ///
     /// This should be implemented consistently with the `branch` method such
Diff in /checkout/library/core/src/ops/try_trait.rs:360:
 /// `<Result<Infallible, E> as Residual<T>>::TryType = Result<T, E>`.
 #[unstable(feature = "try_trait_v2_residual", issue = "91285")]
 #[rustc_const_unstable(feature = "const_try", issue = "74935")]
-pub const trait Residual<O> {
+const pub trait Residual<O> {
     /// The "return" type of this meta-function.
     #[unstable(feature = "try_trait_v2_residual", issue = "91285")]
     type TryType: Try<Output = O, Residual = Self>;
Diff in /checkout/library/core/src/convert/mod.rs:217:
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_diagnostic_item = "AsRef"]
 #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-pub const trait AsRef<T: PointeeSized>: PointeeSized {
+const pub trait AsRef<T: PointeeSized>: PointeeSized {
     /// Converts this type into a shared reference of the (usually inferred) input type.
     #[stable(feature = "rust1", since = "1.0.0")]
     fn as_ref(&self) -> &T;
Diff in /checkout/library/core/src/convert/mod.rs:369:
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_diagnostic_item = "AsMut"]
 #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-pub const trait AsMut<T: PointeeSized>: PointeeSized {
+const pub trait AsMut<T: PointeeSized>: PointeeSized {
     /// Converts this type into a mutable reference of the (usually inferred) input type.
     #[stable(feature = "rust1", since = "1.0.0")]
     fn as_mut(&mut self) -> &mut T;
Diff in /checkout/library/core/src/convert/mod.rs:448:
 #[stable(feature = "rust1", since = "1.0.0")]
 #[doc(search_unbox)]
---
     #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
Diff in /checkout/library/core/src/convert/mod.rs:584:
 ))]
 #[doc(search_unbox)]
 #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-pub const trait From<T>: Sized {
+const pub trait From<T>: Sized {
     /// Converts to this type from the input type.
     #[rustc_diagnostic_item = "from_fn"]
     #[must_use]
Diff in /checkout/library/core/src/convert/mod.rs:612:
 #[rustc_diagnostic_item = "TryInto"]
 #[stable(feature = "try_from", since = "1.34.0")]
 #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-pub const trait TryInto<T>: Sized {
+const pub trait TryInto<T>: Sized {
     /// The type returned in the event of a conversion error.
     #[stable(feature = "try_from", since = "1.34.0")]
     type Error;
Diff in /checkout/library/core/src/convert/mod.rs:691:
 #[rustc_diagnostic_item = "TryFrom"]
 #[stable(feature = "try_from", since = "1.34.0")]
 #[rustc_const_unstable(feature = "const_convert", issue = "143773")]
-pub const trait TryFrom<T>: Sized {
+const pub trait TryFrom<T>: Sized {
     /// The type returned in the event of a conversion error.
     #[stable(feature = "try_from", since = "1.34.0")]
     type Error;
Diff in /checkout/library/core/src/marker.rs:1057:
 #[rustc_on_unimplemented(message = "can't drop `{Self}`", append_const_msg)]
 #[rustc_deny_explicit_impl]
 #[rustc_do_not_implement_via_object]
-pub const trait Destruct {}
+const pub trait Destruct {}
 
 /// A marker for tuple types.
 ///
Diff in /checkout/library/core/src/cmp.rs:248:
 )]
 #[rustc_diagnostic_item = "PartialEq"]
 #[rustc_const_unstable(feature = "const_cmp", issue = "143800")]
-pub const trait PartialEq<Rhs: PointeeSized = Self>: PointeeSized {
+const pub trait PartialEq<Rhs: PointeeSized = Self>: PointeeSized {
     /// Tests for `self` and `other` values to be equal, and is used by `==`.
     #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
Diff in /checkout/library/core/src/default.rs:104:
 #[rustc_diagnostic_item = "Default"]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_default", issue = "143894")]
---
-pub const trait Clone: Sized {
+const pub trait Clone: Sized {
     /// Returns a duplicate of the value.
     ///
     /// Note that what "duplicate" means varies by type:
Diff in /checkout/library/core/src/pat.rs:22:
     message = "`{Self}` is not a valid base type for range patterns",
     label = "only integer types and `char` are supported"
 )]
-pub const trait RangePattern {
+const pub trait RangePattern {
     /// Trait version of the inherent `MIN` assoc const.
     #[lang = "RangeMin"]
     const MIN: Self;
Diff in /checkout/library/core/src/intrinsics/fallback.rs:8:
 #![allow(missing_docs)]
 
 #[rustc_const_unstable(feature = "core_intrinsics_fallbacks", issue = "none")]
-pub const trait CarryingMulAdd: Copy + 'static {
+const pub trait CarryingMulAdd: Copy + 'static {
     type Unsigned: Copy + 'static;
     fn carrying_mul_add(
         self,
Diff in /checkout/library/core/src/intrinsics/fallback.rs:111:
 }
 
 #[rustc_const_unstable(feature = "core_intrinsics_fallbacks", issue = "none")]
-pub const trait DisjointBitOr: Copy + 'static {
+const pub trait DisjointBitOr: Copy + 'static {
     /// See [`super::disjoint_bitor`]; we just need the trait indirection to handle
     /// different types since calling intrinsics with generics doesn't work.
     unsafe fn disjoint_bitor(self, other: Self) -> Self;
Diff in /checkout/library/core/src/str/traits.rs:826:
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]

[npmccallum]

@bjorn3 The tidy test is still failing, even after my fix for rustfmt was merged. What do we need to do? Do we have to pin tidy to a different nightly? I don't know how this works.

[fmease]

Yea we need to repin explicitly, lemme investigate how that works. However, I'm not sure if we even pin to some nightly rustfmt, I thought we pin to a beta rustfmt but I'm probably wrong.

[npmccallum]

@fmease Any luck? I've got multiple PRs blocked on this.