rust-clippy/tests/compile-fail/min_max.rs

#![feature(plugin)]

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

use std::cmp::{min, max};
use std::cmp::min as my_min;
use std::cmp::max as my_max;

const LARGE : usize = 3;

fn main() {
    let x;
    x = 2usize;
    min(1, max(3, x)); //~ERROR this min/max combination leads to constant result
    min(max(3, x), 1); //~ERROR this min/max combination leads to constant result
    max(min(x, 1), 3); //~ERROR this min/max combination leads to constant result
    max(3, min(x, 1)); //~ERROR this min/max combination leads to constant result

    my_max(3, my_min(x, 1)); //~ERROR this min/max combination leads to constant result

    min(3, max(1, x)); // ok, could be 1, 2 or 3 depending on x

    min(1, max(LARGE, x)); // no error, we don't lookup consts here

    let s;
    s = "Hello";

    min("Apple", max("Zoo", s)); //~ERROR this min/max combination leads to constant result
    max(min(s, "Apple"), "Zoo"); //~ERROR this min/max combination leads to constant result

    max("Apple", min(s, "Zoo")); // ok
}