Incorrect suggestion in `while_let_on_iterator` if iterator cannot be moved

[Alexendoo]

Summary

Same as #7846, but for while_let_on_iterator

Lint Name

while_let_on_iterator

Reproducer

I tried this code:

fn main() {
    let mut arr = [vec![1, 2, 3].into_iter()];
    while let Some(x) = arr[0].next() {}
}

I saw this happen:

warning: this loop could be written as a `for` loop
 --> src\main.rs:3:5
  |
3 |     while let Some(x) = arr[0].next() {}
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `for x in arr[0]`
  |
  = note: `#[warn(clippy::while_let_on_iterator)]` on by default

the suggestion causes the error

error[E0508]: cannot move out of type `[std::vec::IntoIter<i32>; 1]`, a non-copy array
 --> src\main.rs:3:14
  |
3 |     for x in arr[0] {}
  |              ^^^^^^
  |              |
  |              cannot move out of here
  |              move occurs because `arr[_]` has type `std::vec::IntoIter<i32>`, which does not implement the `Copy` trait

I expected to see this happen:

No lint emitted

Version

rustc 1.59.0-nightly (e6b883c74 2021-12-08)
binary: rustc
commit-hash: e6b883c74f49f32cb5d1cbad3457f2b8805a4a38
commit-date: 2021-12-08
host: x86_64-pc-windows-msvc
release: 1.59.0-nightly
LLVM version: 13.0.0

Additional Labels

@rustbot label +I-suggestion-causes-error

[WaffleLapkin]

I don't think it's false positive, as there can be correct suggestion:

for x in &mut arr[0] {}
// or
for x in arr[0].by_ref() {}

i.e. if iterator can't be moved we should suggest using unique references to the said iterator

[Alexendoo]

@rustbot label -I-suggestion-causes-error

[Alexendoo]

Whoops, wrong one 👀

@rustbot label +I-suggestion-causes-error -I-false-positive