rust/tests/ui/unnecessary_sort_by.rs
2020-07-08 21:31:59 +02:00

65 lines
1.8 KiB
Rust

// run-rustfix
use std::cmp::Reverse;
fn unnecessary_sort_by() {
fn id(x: isize) -> isize {
x
}
let mut vec: Vec<isize> = vec![3, 6, 1, 2, 5];
// Forward examples
vec.sort_by(|a, b| a.cmp(b));
vec.sort_unstable_by(|a, b| a.cmp(b));
vec.sort_by(|a, b| (a + 5).abs().cmp(&(b + 5).abs()));
vec.sort_unstable_by(|a, b| id(-a).cmp(&id(-b)));
// Reverse examples
vec.sort_by(|a, b| b.cmp(a));
vec.sort_by(|a, b| (b + 5).abs().cmp(&(a + 5).abs()));
vec.sort_unstable_by(|a, b| id(-b).cmp(&id(-a)));
// Negative examples (shouldn't be changed)
let c = &7;
vec.sort_by(|a, b| (b - a).cmp(&(a - b)));
vec.sort_by(|_, b| b.cmp(&5));
vec.sort_by(|_, b| b.cmp(c));
vec.sort_unstable_by(|a, _| a.cmp(c));
}
// Should not be linted to avoid hitting https://github.com/rust-lang/rust/issues/34162
mod issue_5754 {
struct Test(String);
#[derive(PartialOrd, Ord, PartialEq, Eq)]
struct Wrapper<'a>(&'a str);
impl Test {
fn name(&self) -> &str {
&self.0
}
fn wrapped(&self) -> Wrapper<'_> {
Wrapper(&self.0)
}
}
pub fn test() {
let mut args: Vec<Test> = vec![];
// Forward
args.sort_by(|a, b| a.name().cmp(b.name()));
args.sort_by(|a, b| a.wrapped().cmp(&b.wrapped()));
args.sort_unstable_by(|a, b| a.name().cmp(b.name()));
args.sort_unstable_by(|a, b| a.wrapped().cmp(&b.wrapped()));
// Reverse
args.sort_by(|a, b| b.name().cmp(a.name()));
args.sort_by(|a, b| b.wrapped().cmp(&a.wrapped()));
args.sort_unstable_by(|a, b| b.name().cmp(a.name()));
args.sort_unstable_by(|a, b| b.wrapped().cmp(&a.wrapped()));
}
}
fn main() {
unnecessary_sort_by();
issue_5754::test();
}