Fix some false-positive cases of explicit_auto_deref

[tesuji]

changelog: [explicit_auto_deref] Fix some false-positive cases

Fix part of #9841
Fix #12969

r? xFrednet

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[xFrednet]

LGTM, could you explain why #9841 is only partially fixed?

[xFrednet]

And could you also squash your comments down into a single one?

[wr7]

The fix for #9841 does not seem to be general enough.

If you add an extra ref and deref (ie the following code), a false positive still triggers, and an invalid suggestion is still issued.

pub fn takes_array_ref<T, const N: usize>(array: &&&[T; N]) {
    takes_slice(**array) // clippy still suggests to remove both dereferences
}

pub fn takes_slice<T>(_slice: &[T]) {
    todo!()
}

[xFrednet]

That makes sense, thank you :D

Then we're just waiting for a squash of the commits =^.^=

[tesuji]

Then we're just waiting for a squash of the commits =^.^=

Done!

LGTM, could you explain why #9841 is only partially fixed?

That's because of #9841 (comment), which is important too.

[xFrednet]

Thank you!

---

Roses are red,
The CI is green,
Let's merge this quick,
No conflicts seen

[bors]

📌 Commit c4c41d1 has been approved by xFrednet

It is now in the queue for this repository.

[bors]

⌛ Testing commit c4c41d1 with merge 0f4035f...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: xFrednet
Pushing 0f4035f to master...