Fix unnecessary_unwrap emitted twice in closure (#14763)

[relaxcn]

The problem is that check_fn is triggered by both function and closure, and visit_expr can visit expressions in another closures within a function or closure.

So just skip walking in a inner closure.

changelog: Fix [unnecessary_unwrap] emitted twice in closure which inside in a function or another closure.

Fixes: #14763

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[samueltardieu]

LGTM, except for a minor comment fix to explain why we don't recurse into closures

[samueltardieu]

Can you please squash the commits together? Then it will be ready to be merged.

[relaxcn]

Sure.

[relaxcn]

I have a question.

Why using Unwrap::check_fn() instead of check_fn() in your comment?

[samueltardieu]

I have a question.

Why using Unwrap::check_fn() instead of check_fn() in your comment?

No particular reason, except that since check_fn() is not part of the Visitor trait but belongs to the LateLintPass one I thought it was clearer to fully qualify it.

You prefer to use the short form?

[relaxcn]

No, your change looks good for me.

Because I'm new, so I just have some doubts.

Thanks for your reply.

You can merge it now.😊

[relaxcn]

Sory, I just want to make sure what else do I need to do now?

It seems that you need to accept the changes firstly.