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//@run-rustfix
#![warn(clippy::manual_retain)]
#![allow(unused, clippy::redundant_clone)]
use std::collections::BTreeMap;
use std::collections::BTreeSet;
use std::collections::BinaryHeap;
use std::collections::HashMap;
use std::collections::HashSet;
use std::collections::VecDeque;
fn main() {
binary_heap_retain();
btree_set_retain();
btree_map_retain();
hash_set_retain();
hash_map_retain();
string_retain();
vec_deque_retain();
vec_retain();
_msrv_153();
_msrv_126();
_msrv_118();
}
fn binary_heap_retain() {
// NOTE: Do not lint now, because binary_heap_retain is nightly API.
// And we need to add a test case for msrv if we update this implementation.
// https://github.com/rust-lang/rust/issues/71503
let mut heap = BinaryHeap::from([1, 2, 3]);
heap = heap.into_iter().filter(|x| x % 2 == 0).collect();
heap = heap.iter().filter(|&x| x % 2 == 0).copied().collect();
heap = heap.iter().filter(|&x| x % 2 == 0).cloned().collect();
// Do not lint, because type conversion is performed
heap = heap.into_iter().filter(|x| x % 2 == 0).collect::<BinaryHeap<i8>>();
heap = heap.iter().filter(|&x| x % 2 == 0).copied().collect::<BinaryHeap<i8>>();
heap = heap.iter().filter(|&x| x % 2 == 0).cloned().collect::<BinaryHeap<i8>>();
// Do not lint, because this expression is not assign.
let mut bar: BinaryHeap<i8> = heap.iter().filter(|&x| x % 2 == 0).copied().collect();
let mut foobar: BinaryHeap<i8> = heap.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
bar = foobar.iter().filter(|&x| x % 2 == 0).copied().collect();
bar = foobar.into_iter().filter(|x| x % 2 == 0).collect();
}
fn btree_map_retain() {
let mut btree_map: BTreeMap<i8, i8> = (0..8).map(|x| (x, x * 10)).collect();
// Do lint.
btree_map = btree_map.into_iter().filter(|(k, _)| k % 2 == 0).collect();
btree_map = btree_map.into_iter().filter(|(_, v)| v % 2 == 0).collect();
btree_map = btree_map
.into_iter()
.filter(|(k, v)| (k % 2 == 0) && (v % 2 == 0))
.collect();
// Do not lint.
btree_map = btree_map
.into_iter()
.filter(|(x, _)| x % 2 == 0)
.collect::<BTreeMap<i8, i8>>();
// Do not lint, because this expression is not assign.
let mut foobar: BTreeMap<i8, i8> = btree_map.into_iter().filter(|(k, _)| k % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
btree_map = foobar.into_iter().filter(|(k, _)| k % 2 == 0).collect();
}
fn btree_set_retain() {
let mut btree_set = BTreeSet::from([1, 2, 3, 4, 5, 6]);
// Do lint.
btree_set = btree_set.iter().filter(|&x| x % 2 == 0).copied().collect();
btree_set = btree_set.iter().filter(|&x| x % 2 == 0).cloned().collect();
btree_set = btree_set.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because type conversion is performed
btree_set = btree_set
.iter()
.filter(|&x| x % 2 == 0)
.copied()
.collect::<BTreeSet<i8>>();
btree_set = btree_set
.iter()
.filter(|&x| x % 2 == 0)
.cloned()
.collect::<BTreeSet<i8>>();
btree_set = btree_set.into_iter().filter(|x| x % 2 == 0).collect::<BTreeSet<i8>>();
// Do not lint, because this expression is not assign.
let mut foobar: BTreeSet<i8> = btree_set.iter().filter(|&x| x % 2 == 0).copied().collect();
let mut bar: BTreeSet<i8> = btree_set.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
bar = foobar.iter().filter(|&x| x % 2 == 0).copied().collect();
bar = foobar.iter().filter(|&x| x % 2 == 0).cloned().collect();
bar = foobar.into_iter().filter(|x| x % 2 == 0).collect();
}
fn hash_map_retain() {
let mut hash_map: HashMap<i8, i8> = (0..8).map(|x| (x, x * 10)).collect();
// Do lint.
hash_map = hash_map.into_iter().filter(|(k, _)| k % 2 == 0).collect();
hash_map = hash_map.into_iter().filter(|(_, v)| v % 2 == 0).collect();
hash_map = hash_map
.into_iter()
.filter(|(k, v)| (k % 2 == 0) && (v % 2 == 0))
.collect();
// Do not lint.
hash_map = hash_map
.into_iter()
.filter(|(x, _)| x % 2 == 0)
.collect::<HashMap<i8, i8>>();
// Do not lint, because this expression is not assign.
let mut foobar: HashMap<i8, i8> = hash_map.into_iter().filter(|(k, _)| k % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
hash_map = foobar.into_iter().filter(|(k, _)| k % 2 == 0).collect();
}
fn hash_set_retain() {
let mut hash_set = HashSet::from([1, 2, 3, 4, 5, 6]);
// Do lint.
hash_set = hash_set.into_iter().filter(|x| x % 2 == 0).collect();
hash_set = hash_set.iter().filter(|&x| x % 2 == 0).copied().collect();
hash_set = hash_set.iter().filter(|&x| x % 2 == 0).cloned().collect();
// Do not lint, because type conversion is performed
hash_set = hash_set.into_iter().filter(|x| x % 2 == 0).collect::<HashSet<i8>>();
hash_set = hash_set
.iter()
.filter(|&x| x % 2 == 0)
.copied()
.collect::<HashSet<i8>>();
hash_set = hash_set
.iter()
.filter(|&x| x % 2 == 0)
.cloned()
.collect::<HashSet<i8>>();
// Do not lint, because this expression is not assign.
let mut bar: HashSet<i8> = hash_set.iter().filter(|&x| x % 2 == 0).copied().collect();
let mut foobar: HashSet<i8> = hash_set.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
bar = foobar.iter().filter(|&x| x % 2 == 0).copied().collect();
bar = foobar.iter().filter(|&x| x % 2 == 0).cloned().collect();
bar = foobar.into_iter().filter(|&x| x % 2 == 0).collect();
}
fn string_retain() {
let mut s = String::from("foobar");
// Do lint.
s = s.chars().filter(|&c| c != 'o').to_owned().collect();
// Do not lint, because this expression is not assign.
let mut bar: String = s.chars().filter(|&c| c != 'o').to_owned().collect();
// Do not lint, because it is an assignment to a different variable.
s = bar.chars().filter(|&c| c != 'o').to_owned().collect();
}
fn vec_retain() {
let mut vec = vec![0, 1, 2];
// Do lint.
vec = vec.iter().filter(|&x| x % 2 == 0).copied().collect();
vec = vec.iter().filter(|&x| x % 2 == 0).cloned().collect();
vec = vec.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because type conversion is performed
vec = vec.into_iter().filter(|x| x % 2 == 0).collect::<Vec<i8>>();
vec = vec.iter().filter(|&x| x % 2 == 0).copied().collect::<Vec<i8>>();
vec = vec.iter().filter(|&x| x % 2 == 0).cloned().collect::<Vec<i8>>();
// Do not lint, because this expression is not assign.
let mut bar: Vec<i8> = vec.iter().filter(|&x| x % 2 == 0).copied().collect();
let mut foobar: Vec<i8> = vec.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
bar = foobar.iter().filter(|&x| x % 2 == 0).copied().collect();
bar = foobar.iter().filter(|&x| x % 2 == 0).cloned().collect();
bar = foobar.into_iter().filter(|x| x % 2 == 0).collect();
}
fn vec_deque_retain() {
let mut vec_deque = VecDeque::new();
vec_deque.extend(1..5);
// Do lint.
vec_deque = vec_deque.iter().filter(|&x| x % 2 == 0).copied().collect();
vec_deque = vec_deque.iter().filter(|&x| x % 2 == 0).cloned().collect();
vec_deque = vec_deque.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because type conversion is performed
vec_deque = vec_deque
.iter()
.filter(|&x| x % 2 == 0)
.copied()
.collect::<VecDeque<i8>>();
vec_deque = vec_deque
.iter()
.filter(|&x| x % 2 == 0)
.cloned()
.collect::<VecDeque<i8>>();
vec_deque = vec_deque.into_iter().filter(|x| x % 2 == 0).collect::<VecDeque<i8>>();
// Do not lint, because this expression is not assign.
let mut bar: VecDeque<i8> = vec_deque.iter().filter(|&x| x % 2 == 0).copied().collect();
let mut foobar: VecDeque<i8> = vec_deque.into_iter().filter(|x| x % 2 == 0).collect();
// Do not lint, because it is an assignment to a different variable.
bar = foobar.iter().filter(|&x| x % 2 == 0).copied().collect();
bar = foobar.iter().filter(|&x| x % 2 == 0).cloned().collect();
bar = foobar.into_iter().filter(|x| x % 2 == 0).collect();
}
#[clippy::msrv = "1.52"]
fn _msrv_153() {
let mut btree_map: BTreeMap<i8, i8> = (0..8).map(|x| (x, x * 10)).collect();
btree_map = btree_map.into_iter().filter(|(k, _)| k % 2 == 0).collect();
let mut btree_set = BTreeSet::from([1, 2, 3, 4, 5, 6]);
btree_set = btree_set.iter().filter(|&x| x % 2 == 0).copied().collect();
}
#[clippy::msrv = "1.25"]
fn _msrv_126() {
let mut s = String::from("foobar");
s = s.chars().filter(|&c| c != 'o').to_owned().collect();
}
#[clippy::msrv = "1.17"]
fn _msrv_118() {
let mut hash_set = HashSet::from([1, 2, 3, 4, 5, 6]);
hash_set = hash_set.into_iter().filter(|x| x % 2 == 0).collect();
let mut hash_map: HashMap<i8, i8> = (0..8).map(|x| (x, x * 10)).collect();
hash_map = hash_map.into_iter().filter(|(k, _)| k % 2 == 0).collect();
}
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