Wrong matching with enums and overlapping ranges

[seanmonstar]

#[deriving(Show)]
enum State {
    AtoZ(uint),
    Numeric,
}


fn main() {
    let state = Numeric;
    let b = 97u8; // a
    let r = match (state, b as char) {
        (AtoZ(..), 'a'..'z') => {
            "Named"
        },

        (Numeric, 'x') => {
            "Hex"
        },


        _ => {
            "Other"
        }
    };
    println!("{} {}: {}", state, b as char, r);
}

Outputs Numeric a: Hex. Clearly, a shouldn't match x.

Worth noting: if you change the first range to not include x, such as a..w, it works correctly. Also, removing the field from AtoZ also makes the match work correctly.

[seanmonstar]

blocking #13831

[lilyball]

cc me

[edwardw]

This seems to be a regression introduced by #13034.

[lilyball]

This is impacting #13896 as well. I had to add in guards that re-test the range to work around it.

[edwardw]

The defect of #13034 is that it doesn't check multiple refutable patterns, which is exactly what this bug report is about.