False positive redundant_closure when using ref pattern in closure params

[cdmistman]

Summary

Related to #3071 which was fixed in #7661, I found a bug when using the ref pattern in a closure's parameters ie |ref foo| bar(foo)

Lint Name

redundant-closure

Reproducer

I tried this code:

struct Foo;

struct Bar;

impl From<&Foo> for Bar {
    fn from(foo: &Foo) -> Self {
        Bar
    }
}

fn main() {
    // this doesn't trigger redundant-closure, as expected
    Some(Foo).map(|foo| Bar::from(&foo));
    // this triggers redundant-closure
    Some(Foo).map(|ref foo| Bar::from(foo));
    // this causes a compiler error since `From<Foo> for Bar` is not implemented
    // Some(Foo).map(Bar::from);
}

Note that the first statement in main triggers expected behavior - there is no redundant closure, and so the lint is not triggered. However, as in the issue referenced above, redundant-closure is triggered for the second statement, with the suggestion being the third (commented-out) statement - this is unexpected behavior, since the suggested code fails to type-check and causes a compiler error.

playground (with allows to isolate lint): https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=ec6a0ed2580e8fc73146abf6ada9b384

Version

No response

Additional Labels

No response

[tamaroning]

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