rust/library/core/tests/cmp.rs
2023-04-16 11:38:52 +00:00

253 lines
6.5 KiB
Rust

use core::cmp::{
self,
Ordering::{self, *},
};
#[test]
fn test_int_totalord() {
assert_eq!(5.cmp(&10), Less);
assert_eq!(10.cmp(&5), Greater);
assert_eq!(5.cmp(&5), Equal);
assert_eq!((-5).cmp(&12), Less);
assert_eq!(12.cmp(&-5), Greater);
}
#[test]
fn test_bool_totalord() {
assert_eq!(true.cmp(&false), Greater);
assert_eq!(false.cmp(&true), Less);
assert_eq!(true.cmp(&true), Equal);
assert_eq!(false.cmp(&false), Equal);
}
#[test]
fn test_mut_int_totalord() {
assert_eq!((&mut 5).cmp(&&mut 10), Less);
assert_eq!((&mut 10).cmp(&&mut 5), Greater);
assert_eq!((&mut 5).cmp(&&mut 5), Equal);
assert_eq!((&mut -5).cmp(&&mut 12), Less);
assert_eq!((&mut 12).cmp(&&mut -5), Greater);
}
#[test]
fn test_ord_max_min() {
assert_eq!(1.max(2), 2);
assert_eq!(2.max(1), 2);
assert_eq!(1.min(2), 1);
assert_eq!(2.min(1), 1);
assert_eq!(1.max(1), 1);
assert_eq!(1.min(1), 1);
}
#[test]
fn test_ord_min_max_by() {
let f = |x: &i32, y: &i32| x.abs().cmp(&y.abs());
assert_eq!(cmp::min_by(1, -1, f), 1);
assert_eq!(cmp::min_by(1, -2, f), 1);
assert_eq!(cmp::min_by(2, -1, f), -1);
assert_eq!(cmp::max_by(1, -1, f), -1);
assert_eq!(cmp::max_by(1, -2, f), -2);
assert_eq!(cmp::max_by(2, -1, f), 2);
}
#[test]
fn test_ord_min_max_by_key() {
let f = |x: &i32| x.abs();
assert_eq!(cmp::min_by_key(1, -1, f), 1);
assert_eq!(cmp::min_by_key(1, -2, f), 1);
assert_eq!(cmp::min_by_key(2, -1, f), -1);
assert_eq!(cmp::max_by_key(1, -1, f), -1);
assert_eq!(cmp::max_by_key(1, -2, f), -2);
assert_eq!(cmp::max_by_key(2, -1, f), 2);
}
#[test]
fn test_ordering_reverse() {
assert_eq!(Less.reverse(), Greater);
assert_eq!(Equal.reverse(), Equal);
assert_eq!(Greater.reverse(), Less);
}
#[test]
fn test_ordering_order() {
assert!(Less < Equal);
assert_eq!(Greater.cmp(&Less), Greater);
}
#[test]
fn test_ordering_then() {
assert_eq!(Equal.then(Less), Less);
assert_eq!(Equal.then(Equal), Equal);
assert_eq!(Equal.then(Greater), Greater);
assert_eq!(Less.then(Less), Less);
assert_eq!(Less.then(Equal), Less);
assert_eq!(Less.then(Greater), Less);
assert_eq!(Greater.then(Less), Greater);
assert_eq!(Greater.then(Equal), Greater);
assert_eq!(Greater.then(Greater), Greater);
}
#[test]
fn test_ordering_then_with() {
assert_eq!(Equal.then_with(|| Less), Less);
assert_eq!(Equal.then_with(|| Equal), Equal);
assert_eq!(Equal.then_with(|| Greater), Greater);
assert_eq!(Less.then_with(|| Less), Less);
assert_eq!(Less.then_with(|| Equal), Less);
assert_eq!(Less.then_with(|| Greater), Less);
assert_eq!(Greater.then_with(|| Less), Greater);
assert_eq!(Greater.then_with(|| Equal), Greater);
assert_eq!(Greater.then_with(|| Greater), Greater);
}
#[test]
fn test_user_defined_eq() {
// Our type.
struct SketchyNum {
num: isize,
}
// Our implementation of `PartialEq` to support `==` and `!=`.
impl PartialEq for SketchyNum {
// Our custom eq allows numbers which are near each other to be equal! :D
fn eq(&self, other: &SketchyNum) -> bool {
(self.num - other.num).abs() < 5
}
}
// Now these binary operators will work when applied!
assert!(SketchyNum { num: 37 } == SketchyNum { num: 34 });
assert!(SketchyNum { num: 25 } != SketchyNum { num: 57 });
}
#[test]
fn ordering_const() {
// test that the methods of `Ordering` are usable in a const context
const ORDERING: Ordering = Greater;
const REVERSE: Ordering = ORDERING.reverse();
assert_eq!(REVERSE, Less);
const THEN: Ordering = Equal.then(ORDERING);
assert_eq!(THEN, Greater);
}
#[test]
fn ordering_structural_eq() {
// test that consts of type `Ordering` are usable in patterns
const ORDERING: Ordering = Greater;
const REVERSE: Ordering = ORDERING.reverse();
match Ordering::Less {
REVERSE => {}
_ => unreachable!(),
};
}
#[test]
fn cmp_default() {
// Test default methods in PartialOrd and PartialEq
#[derive(Debug)]
struct Fool(bool);
impl PartialEq for Fool {
fn eq(&self, other: &Fool) -> bool {
let Fool(this) = *self;
let Fool(other) = *other;
this != other
}
}
struct Int(isize);
impl PartialEq for Int {
fn eq(&self, other: &Int) -> bool {
let Int(this) = *self;
let Int(other) = *other;
this == other
}
}
impl PartialOrd for Int {
fn partial_cmp(&self, other: &Int) -> Option<Ordering> {
let Int(this) = *self;
let Int(other) = *other;
this.partial_cmp(&other)
}
}
struct RevInt(isize);
impl PartialEq for RevInt {
fn eq(&self, other: &RevInt) -> bool {
let RevInt(this) = *self;
let RevInt(other) = *other;
this == other
}
}
impl PartialOrd for RevInt {
fn partial_cmp(&self, other: &RevInt) -> Option<Ordering> {
let RevInt(this) = *self;
let RevInt(other) = *other;
other.partial_cmp(&this)
}
}
assert!(Int(2) > Int(1));
assert!(Int(2) >= Int(1));
assert!(Int(1) >= Int(1));
assert!(Int(1) < Int(2));
assert!(Int(1) <= Int(2));
assert!(Int(1) <= Int(1));
assert!(RevInt(2) < RevInt(1));
assert!(RevInt(2) <= RevInt(1));
assert!(RevInt(1) <= RevInt(1));
assert!(RevInt(1) > RevInt(2));
assert!(RevInt(1) >= RevInt(2));
assert!(RevInt(1) >= RevInt(1));
assert_eq!(Fool(true), Fool(false));
assert!(Fool(true) != Fool(true));
assert!(Fool(false) != Fool(false));
assert_eq!(Fool(false), Fool(true));
}
/* FIXME(#110395)
mod const_cmp {
use super::*;
struct S(i32);
impl PartialEq for S {
fn eq(&self, other: &Self) -> bool {
self.0 == other.0
}
}
impl PartialOrd for S {
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
let ret = match (self.0, other.0) {
(a, b) if a > b => Ordering::Greater,
(a, b) if a < b => Ordering::Less,
_ => Ordering::Equal,
};
Some(ret)
}
}
const _: () = assert!(S(1) == S(1));
const _: () = assert!(S(0) != S(1));
const _: () = assert!(S(1) <= S(1));
const _: () = assert!(S(1) >= S(1));
const _: () = assert!(S(0) < S(1));
const _: () = assert!(S(1) > S(0));
}
*/