rust/tests/compile-fail/reference.rs

#![feature(plugin)]
#![plugin(clippy)]

fn get_number() -> usize {
    10
}

fn get_reference(n : &usize) -> &usize {
    n
}

#[allow(many_single_char_names)]
#[allow(unused_variables)]
#[deny(deref_addrof)]
fn main() {
    let a = 10;
    let aref = &a;

    let b = *&a;
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = a;

    let b = *&get_number();
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = get_number();

    let b = *get_reference(&a);

    let bytes : Vec<usize> = vec![1, 2, 3, 4];
    let b = *&bytes[1..2][0];
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = bytes[1..2][0];

    //This produces a suggestion of 'let b = (a);' which
    //will trigger the 'unused_parens' lint
    let b = *&(a);
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = (a)

    let b = *(&a);
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = a;

    let b = *((&a));
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = a

    let b = *&&a;
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = &a;

    let b = **&aref;
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = *aref;

    //This produces a suggestion of 'let b = *&a;' which
    //will trigger the 'deref_addrof' lint again
    let b = **&&a;
    //~^ERROR immediately dereferencing a reference
    //~|HELP try this
    //~|SUGGESTION let b = *&a;

    {
        let mut x = 10;
        let y = *&mut x;
        //~^ERROR immediately dereferencing a reference
        //~|HELP try this
        //~|SUGGESTION let y = x;
    }

    {
        //This produces a suggestion of 'let y = *&mut x' which
        //will trigger the 'deref_addrof' lint again
        let mut x = 10;
        let y = **&mut &mut x;
        //~^ERROR immediately dereferencing a reference
        //~|HELP try this
        //~|SUGGESTION let y = *&mut x;
    }
}