rust/tests/ui/iter_with_drain.rs

66 lines
2.2 KiB
Rust

//@run-rustfix
// will emits unused mut warnings after fixing
#![allow(unused_mut)]
// will emits needless collect warnings after fixing
#![allow(clippy::needless_collect, clippy::drain_collect)]
#![warn(clippy::iter_with_drain)]
use std::collections::{BinaryHeap, HashMap, HashSet, VecDeque};
fn full() {
let mut a = vec!["aaa".to_string(), "bbb".to_string()];
let mut a: BinaryHeap<_> = a.drain(..).collect();
let mut a: HashSet<_> = a.drain().collect();
let mut a: VecDeque<_> = a.drain().collect();
let mut a: Vec<_> = a.drain(..).collect();
let mut a: HashMap<_, _> = a.drain(..).map(|x| (x.clone(), x)).collect();
let _: Vec<(String, String)> = a.drain().collect();
}
fn closed() {
let mut a = vec!["aaa".to_string(), "bbb".to_string()];
let mut a: BinaryHeap<_> = a.drain(0..).collect();
let mut a: HashSet<_> = a.drain().collect();
let mut a: VecDeque<_> = a.drain().collect();
let mut a: Vec<_> = a.drain(..a.len()).collect();
let mut a: HashMap<_, _> = a.drain(0..a.len()).map(|x| (x.clone(), x)).collect();
let _: Vec<(String, String)> = a.drain().collect();
}
fn should_not_help() {
let mut a = vec!["aaa".to_string(), "bbb".to_string()];
let mut a: BinaryHeap<_> = a.drain(1..).collect();
let mut a: HashSet<_> = a.drain().collect();
let mut a: VecDeque<_> = a.drain().collect();
let mut a: Vec<_> = a.drain(..a.len() - 1).collect();
let mut a: HashMap<_, _> = a.drain(1..a.len() - 1).map(|x| (x.clone(), x)).collect();
let _: Vec<(String, String)> = a.drain().collect();
let mut b = vec!["aaa".to_string(), "bbb".to_string()];
let _: Vec<_> = b.drain(0..a.len()).collect();
}
fn _closed_range(mut x: Vec<String>) {
let _: Vec<String> = x.drain(0..=x.len()).collect();
}
fn _with_mut(x: &mut Vec<String>, y: &mut VecDeque<String>) {
let _: Vec<String> = x.drain(..).collect();
let _: Vec<String> = y.drain(..).collect();
}
#[derive(Default)]
struct Bomb {
fire: Vec<u8>,
}
fn should_not_help_0(bomb: &mut Bomb) {
let _: Vec<u8> = bomb.fire.drain(..).collect();
}
fn main() {
full();
closed();
should_not_help();
should_not_help_0(&mut Bomb::default());
}