`iter.map(...).any(identity)` into `iter.any(...)`

What it does

Make the code more concise

Advantage

• Less code
• simple

Drawbacks

No response

Example

pub fn foo<'a, T: AsRef<str> + 'a>(iter: impl Iterator<Item = &'a T>) -> bool {
    iter.map(AsRef::as_ref)
        .map(|s| s.is_empty())
        .any(|i| i)
}
pub fn bar<'a, T: AsRef<str> + 'a>(iter: impl Iterator<Item = &'a T>) -> bool {
    iter.map(AsRef::as_ref)
        .map(|s| s.is_empty())
        .any(core::convert::identity)
}
pub fn baz<'a, T: AsRef<str> + 'a>(iter: impl Iterator<Item = &'a T>) -> bool {
    iter.map(AsRef::as_ref)
        .map(|s| s.is_empty())
        .all(core::convert::identity)
}

Could be written as:

pub fn foo<'a, T: AsRef<str> + 'a>(iter: impl Iterator<Item = &'a T>) -> bool {
    iter.map(AsRef::as_ref)
        .any(|s| s.is_empty())
}
pub fn bar<'a, T: AsRef<str> + 'a>(iter: impl Iterator<Item = &'a T>) -> bool {
    iter.map(AsRef::as_ref)
        .any(|s| s.is_empty())
}
pub fn baz<'a, T: AsRef<str> + 'a>(iter: impl Iterator<Item = &'a T>) -> bool {
    iter.map(AsRef::as_ref)
        .all(|s| s.is_empty())
}

Iterator::any and Iterator::all

Start with the issue's Rust examples and the documentation for Iterator::any and Iterator::all. Identify the existing Clippy lint and test locations for iterator simplifications, then check how equivalent identity closures are represented. Done means the proposed redundant mapping and predicate forms are recognized with appropriate tests and diagnostics.