47 lines
1.3 KiB
Rust
47 lines
1.3 KiB
Rust
|
// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
|
||
|
|
// file at the top-level directory of this distribution and at
|
||
|
|
// http://rust-lang.org/COPYRIGHT.
|
||
|
|
//
|
||
|
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
||
|
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
||
|
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
||
|
|
// option. This file may not be copied, modified, or distributed
|
||
|
|
// except according to those terms.
|
||
|
|
|
||
|
|
// check that the derived impls for the comparison traits shortcircuit
|
||
|
|
// where possible, by having a type that fails when compared as the
|
||
|
|
// second element, so this passes iff the instances shortcircuit.
|
||
|
|
|
||
|
|
pub struct FailCmp;
|
||
|
|
impl Eq for FailCmp {
|
||
|
|
fn eq(&self, _: &FailCmp) -> bool { fail!("eq") }
|
||
|
|
}
|
||
|
|
|
||
|
|
impl Ord for FailCmp {
|
||
|
|
fn lt(&self, _: &FailCmp) -> bool { fail!("lt") }
|
||
|
|
}
|
||
|
|
|
||
|
|
impl TotalEq for FailCmp {
|
||
|
|
fn equals(&self, _: &FailCmp) -> bool { fail!("equals") }
|
||
|
|
}
|
||
|
|
|
||
|
|
impl TotalOrd for FailCmp {
|
||
|
|
fn cmp(&self, _: &FailCmp) -> Ordering { fail!("cmp") }
|
||
|
|
}
|
||
|
|
|
||
|
|
#[deriving(Eq,Ord,TotalEq,TotalOrd)]
|
||
|
|
struct ShortCircuit {
|
||
|
|
x: int,
|
||
|
|
y: FailCmp
|
||
|
|
}
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
let a = ShortCircuit { x: 1, y: FailCmp };
|
||
|
|
let b = ShortCircuit { x: 2, y: FailCmp };
|
||
|
|
|
||
|
|
assert!(a != b);
|
||
|
|
assert!(a < b);
|
||
|
|
assert!(!a.equals(&b));
|
||
|
|
assert_eq!(a.cmp(&b), ::std::cmp::Less);
|
||
|
|
}
|