rust/tests/ui/neg_cmp_op_on_partial_ord.rs
Bruno Kirschner fedd3ef711 Allows neg_cmp_op_on_partial_ord for external macros (fixes #2856).
The macro always negates the result of the given comparison in its
internal check which automatically triggered the lint. As its an
external macro there was no chance to do anything about it which lead
to a white listing of all external macros to prevent further issues.
2018-06-20 11:58:15 +02:00

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 comparision 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 lead
// to a whitelisting of all external macros.
assert!(a_value < another_value);
}