match_single_binding suggest wrong code

[jo-so]

Summary

The code suggestion of clippy doesn't work.

warning: this match could be written as a `let` statement
  --> src/html_output.rs:59:19
   |
59 |               val = match val.split_at(idx) {
   |  ___________________^
60 | |                 (pre, suf) => {
61 | |                     pre.write_to(out)?;
62 | |                     suf
63 | |                 }
64 | |             };
   | |_____________^
   |
   = note: `#[warn(clippy::match_single_binding)]` on by default
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_single_binding
help: consider using `let` statement
   |
59 ~             val = let (pre, suf) = val.split_at(idx);
60 +             {
61 +                 pre.write_to(out)?;
62 +                 suf
63 ~             };
   |

Reproducer

I tried this code:

fn main() {
    let (mut val, idx) = ("a b", 1);

    val = match val.split_at(idx) {
        (pre, suf) => {
            println!("{}", pre);
            suf
        }
    };

    let _ = val;
}

I expected to see this happen:

59 ~             val = {
60 +                 let (pre, suf) = val.split_at(idx);
61 +                 pre.write_to(out)?;
62 +                 suf
63 ~             };

Instead, this happened:

59 ~             val = let (pre, suf) = val.split_at(idx);
60 +             {
61 +                 pre.write_to(out)?;
62 +                 suf
63 ~             };

Version

rustc 1.62.0-nightly (311e2683e 2022-04-18)
binary: rustc
commit-hash: 311e2683e1bad87715b1558f7900e294d24ce491
commit-date: 2022-04-18
host: x86_64-unknown-linux-gnu
release: 1.62.0-nightly
LLVM version: 14.0.1

clippy 0.1.62 (311e268 2022-04-18)

Additional Labels

No response

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