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#![allow(unused, clippy::needless_if, clippy::suspicious_map, clippy::iter_count)]
use std::collections::{BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet, LinkedList};
#[warn(clippy::needless_collect)]
#[allow(unused_variables, clippy::iter_cloned_collect, clippy::iter_next_slice)]
fn main() {
let sample = [1; 5];
let len = sample.iter().collect::<Vec<_>>().len();
if sample.iter().collect::<Vec<_>>().is_empty() {
// Empty
}
sample.iter().cloned().collect::<Vec<_>>().contains(&1);
// #7164 HashMap's and BTreeMap's `len` usage should not be linted
sample.iter().map(|x| (x, x)).collect::<HashMap<_, _>>().len();
sample.iter().map(|x| (x, x)).collect::<BTreeMap<_, _>>().len();
sample.iter().map(|x| (x, x)).collect::<HashMap<_, _>>().is_empty();
sample.iter().map(|x| (x, x)).collect::<BTreeMap<_, _>>().is_empty();
// Notice the `HashSet`--this should not be linted
sample.iter().collect::<HashSet<_>>().len();
// Neither should this
sample.iter().collect::<BTreeSet<_>>().len();
sample.iter().collect::<LinkedList<_>>().len();
sample.iter().collect::<LinkedList<_>>().is_empty();
sample.iter().cloned().collect::<LinkedList<_>>().contains(&1);
sample.iter().collect::<LinkedList<_>>().contains(&&1);
// `BinaryHeap` doesn't have `contains` method
sample.iter().collect::<BinaryHeap<_>>().len();
sample.iter().collect::<BinaryHeap<_>>().is_empty();
// Don't lint string from str
let _ = ["", ""].into_iter().collect::<String>().is_empty();
let _ = sample.iter().collect::<HashSet<_>>().is_empty();
let _ = sample.iter().collect::<HashSet<_>>().contains(&&0);
struct VecWrapper<T>(Vec<T>);
impl<T> core::ops::Deref for VecWrapper<T> {
type Target = Vec<T>;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl<T> IntoIterator for VecWrapper<T> {
type IntoIter = <Vec<T> as IntoIterator>::IntoIter;
type Item = <Vec<T> as IntoIterator>::Item;
fn into_iter(self) -> Self::IntoIter {
self.0.into_iter()
}
}
impl<T> FromIterator<T> for VecWrapper<T> {
fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self {
Self(Vec::from_iter(iter))
}
}
let _ = sample.iter().collect::<VecWrapper<_>>().is_empty();
let _ = sample.iter().collect::<VecWrapper<_>>().contains(&&0);
#[allow(clippy::double_parens)]
{
Vec::<u8>::new().extend((0..10).collect::<Vec<_>>());
foo((0..10).collect::<Vec<_>>());
bar((0..10).collect::<Vec<_>>(), (0..10).collect::<Vec<_>>());
baz((0..10), (), ('a'..='z').collect::<Vec<_>>())
}
let values = [1, 2, 3, 4];
let mut out = vec![];
values.iter().cloned().map(|x| out.push(x)).collect::<Vec<_>>();
let _y = values.iter().cloned().map(|x| out.push(x)).collect::<Vec<_>>(); // this is fine
}
fn foo(_: impl IntoIterator<Item = usize>) {}
fn bar<I: IntoIterator<Item = usize>>(_: Vec<usize>, _: I) {}
fn baz<I: IntoIterator<Item = usize>>(_: I, _: (), _: impl IntoIterator<Item = char>) {}
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