Rollup merge of #94868 - dtolnay:noblock, r=Dylan-DPC

Format core and std macro rules, removing needless surrounding blocks

Many of the asserting and printing macros in `core` and `std` are written with prehistoric-looking formatting, like this:

https://github.com/rust-lang/rust/blob/335ffbfa547df94ac236f5c56130cecf99c8d82b/library/std/src/macros.rs#L96-L101

In modern Rust style this would conventionally be written as follows instead, always using braces and a trailing semicolon on the macro arms:

https://github.com/rust-lang/rust/blob/af53809c874e0afb7be966df4d3cfcaa05277c53/library/std/src/macros.rs#L98-L105

Getting rid of the unneeded braces inside the expansion reduces extraneous indentation in macro-expanded code. For example:

```rust
println!("repro {}", true);
```

```rust
// before:

{
    ::std::io::_print(
        ::core::fmt::Arguments::new_v1(
            &["repro ", "\n"],
            &[::core::fmt::ArgumentV1::new_display(&true)],
        ),
    );
};
```

```rust
// after:

::std::io::_print(
    ::core::fmt::Arguments::new_v1(
        &["repro ", "\n"],
        &[::core::fmt::ArgumentV1::new_display(&true)],
    ),
);
```

3 files changed, 3 insertions, 3 deletions

diff --git a/src/test/ui/macros/trace-macro.stderr b/src/test/ui/macros/trace-macro.stderr
index 43272248c28..c8a0fd68430 100644
--- a/src/test/ui/macros/trace-macro.stderr
+++ b/src/test/ui/macros/trace-macro.stderr
@@ -5,5 +5,5 @@ LL |     println!("Hello, World!");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: expanding `println! { "Hello, World!" }`
-   = note: to `{ $crate :: io :: _print($crate :: format_args_nl! ("Hello, World!")) ; }`
+   = note: to `$crate :: io :: _print($crate :: format_args_nl! ("Hello, World!"))`
 
diff --git a/src/test/ui/parser/issues/issue-62894.stderr b/src/test/ui/parser/issues/issue-62894.stderr
index 9b7bd1559cd..ed5e863bd9d 100644
--- a/src/test/ui/parser/issues/issue-62894.stderr
+++ b/src/test/ui/parser/issues/issue-62894.stderr
@@ -45,7 +45,7 @@ LL | fn main() {}
    |
   ::: $SRC_DIR/core/src/macros/mod.rs:LL:COL
    |
-LL |     ($left:expr, $right:expr $(,)?) => ({
+LL |     ($left:expr, $right:expr $(,)?) => {
    |      ---------- while parsing argument for this `expr` macro fragment
 
 error: aborting due to 4 previous errors
diff --git a/src/test/ui/pattern/usefulness/tuple-struct-nonexhaustive.stderr b/src/test/ui/pattern/usefulness/tuple-struct-nonexhaustive.stderr
index fc0430d06fa..e2a65ff8524 100644
--- a/src/test/ui/pattern/usefulness/tuple-struct-nonexhaustive.stderr
+++ b/src/test/ui/pattern/usefulness/tuple-struct-nonexhaustive.stderr
@@ -12,7 +12,7 @@ LL | struct Foo(isize, isize);
    = note: the matched value is of type `Foo`
 help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
    |
-LL ~         Foo(2, b) => println!("{}", b)
+LL ~         Foo(2, b) => println!("{}", b),
 LL +         Foo(_, _) => todo!()
    |