rust/tests/ui/neg_cmp_op_on_partial_ord.rs

68 lines
2.0 KiB
Rust

//! This test case utilizes `f64` an easy example for `PartialOrd` only types
//! but the lint itself actually validates any expression where the left
//! operand implements `PartialOrd` but not `Ord`.
use std::cmp::Ordering;
#[warn(neg_cmp_op_on_partial_ord)]
fn main() {
let a_value = 1.0;
let another_value = 7.0;
// --- Bad ---
// Not Less but potentially Greater, Equal or Uncomparable.
let _not_less = !(a_value < another_value);
// Not Less or Equal but potentially Greater or Uncomparable.
let _not_less_or_equal = !(a_value <= another_value);
// Not Greater but potentially Less, Equal or Uncomparable.
let _not_greater = !(a_value > another_value);
// Not Greater or Equal but potentially Less or Uncomparable.
let _not_greater_or_equal = !(a_value >= another_value);
// --- Good ---
let _not_less = match a_value.partial_cmp(&another_value) {
None | Some(Ordering::Greater) | Some(Ordering::Equal) => true,
_ => false,
};
let _not_less_or_equal = match a_value.partial_cmp(&another_value) {
None | Some(Ordering::Greater) => true,
_ => false,
};
let _not_greater = match a_value.partial_cmp(&another_value) {
None | Some(Ordering::Less) | Some(Ordering::Equal) => true,
_ => false,
};
let _not_greater_or_equal = match a_value.partial_cmp(&another_value) {
None | Some(Ordering::Less) => true,
_ => false,
};
// --- Should not trigger ---
let _ = a_value < another_value;
let _ = a_value <= another_value;
let _ = a_value > another_value;
let _ = a_value >= another_value;
// --- regression tests ---
// Issue 2856: False positive on assert!()
//
// The macro always negates the result of the given comparison in its
// internal check which automatically triggered the lint. As it's an
// external macro there was no chance to do anything about it which led
// to a whitelisting of all external macros.
assert!(a_value < another_value);
}