Suggestion for `useless_conversion` with `.into_iter()` could be better

[samueltardieu]

Description

This code :

fn main() {
    let x = &[1];
    let y = &&[2];
    let _ = x.iter().zip(y.into_iter());
}

will suggest to use

    let _ = x.iter().zip(&**y);

while it could suggest

    let _ = x.iter().zip(*y);

Noticed while closing #11572 as completed.

Version

rustc 1.89.0-nightly (4d051fb30 2025-05-18)
binary: rustc
commit-hash: 4d051fb306e661654d088892e02e69b8c0c39d43
commit-date: 2025-05-18
host: x86_64-unknown-linux-gnu
release: 1.89.0-nightly
LLVM version: 20.1.5

Additional Labels

@rustbot label +good first issue +C-enhancement

The adjustments application could be more subtle and stop when it reaches the right type if no Deref/DerefMut adjustment is involved.

[rustbot]

Unknown labels: good, first, issue

[samueltardieu]

@rustbot label +"good first issue"

[rustbot]

Error: Parsing relabel command in comment failed: ...' label +' | error: quote in word at >| '"good firs'...

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