Should the `mut_from_ref` lint apply to unsafe functions?

pub struct MutUnsafeSlice<'s>(&'s mut [u32]);
struct Foo {}
impl Foo {
    pub unsafe fn foo(&self) -> &mut [u32] {
        panic!()
    }
    pub unsafe fn foo1(&self) -> MutUnsafeSlice {
        panic!()
    }
}
fn main() {}

playground

Should mut_from_ref apply to unsafe functions as well?

It is trivial to work around that error by wrapping the mutable reference in a new struct.

Here is the refcell implementation that does something very similar.

I personally don't have any strong opinions in either direction. I just needed to implement something similar to RefCell (runtime borrowing) and I ran into this lint.

Reproduce the provided Rust snippet in the linked Playground and observe how the mut_from_ref lint treats the unsafe functions. Read the linked RefCell implementation for the analogous pattern, then decide whether unsafe functions should be diagnosed and capture the decision in an appropriate regression test.