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#![allow(
unused,
clippy::needless_if,
clippy::suspicious_map,
clippy::iter_count,
clippy::manual_contains
)]
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().count();
//~^ needless_collect
if sample.iter().next().is_none() {
//~^ needless_collect
// Empty
}
sample.iter().cloned().any(|x| x == 1);
//~^ needless_collect
// #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)).next().is_none();
//~^ needless_collect
sample.iter().map(|x| (x, x)).next().is_none();
//~^ needless_collect
// Notice the `HashSet`--this should not be linted
sample.iter().collect::<HashSet<_>>().len();
// Neither should this
sample.iter().collect::<BTreeSet<_>>().len();
sample.iter().count();
//~^ needless_collect
sample.iter().next().is_none();
//~^ needless_collect
sample.iter().cloned().any(|x| x == 1);
//~^ needless_collect
sample.iter().any(|x| x == &1);
//~^ needless_collect
// `BinaryHeap` doesn't have `contains` method
sample.iter().count();
//~^ needless_collect
sample.iter().next().is_none();
//~^ needless_collect
// Don't lint string from str
let _ = ["", ""].into_iter().collect::<String>().is_empty();
let _ = sample.iter().next().is_none();
//~^ needless_collect
let _ = sample.iter().any(|x| x == &0);
//~^ needless_collect
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().next().is_none();
//~^ needless_collect
let _ = sample.iter().any(|x| x == &0);
//~^ needless_collect
#[allow(clippy::double_parens)]
{
Vec::<u8>::new().extend((0..10));
//~^ needless_collect
foo((0..10));
//~^ needless_collect
bar((0..10).collect::<Vec<_>>(), (0..10));
//~^ needless_collect
baz((0..10), (), ('a'..='z'))
//~^ needless_collect
}
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
// Don't write a warning if we call `clone()` on the iterator
// https://github.com/rust-lang/rust-clippy/issues/13430
let my_collection: Vec<()> = vec![()].into_iter().map(|()| {}).collect();
let _cloned = my_collection.into_iter().clone();
let my_collection: Vec<()> = vec![()].into_iter().map(|()| {}).collect();
let my_iter = my_collection.into_iter();
let _cloned = my_iter.clone();
// Same for `as_slice()`, for same reason.
let my_collection: Vec<()> = vec![()].into_iter().map(|()| {}).collect();
let _sliced = my_collection.into_iter().as_slice();
let my_collection: Vec<()> = vec![()].into_iter().map(|()| {}).collect();
let my_iter = my_collection.into_iter();
let _sliced = my_iter.as_slice();
// Assignment outside of main scope
{
let x;
{
let xxx: Vec<()> = vec![()].into_iter().map(|()| {}).collect();
x = xxx.into_iter();
for i in x.as_slice() {}
}
}
}
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>) {}
mod issue9191 {
use std::cell::Cell;
use std::collections::HashSet;
use std::hash::Hash;
use std::marker::PhantomData;
use std::ops::Deref;
fn captures_ref_mut(xs: Vec<i32>, mut ys: HashSet<i32>) {
if xs.iter().map(|x| ys.remove(x)).collect::<Vec<_>>().contains(&true) {
todo!()
}
}
#[derive(Debug, Clone)]
struct MyRef<'a>(PhantomData<&'a mut Cell<HashSet<i32>>>, *mut Cell<HashSet<i32>>);
impl MyRef<'_> {
fn new(target: &mut Cell<HashSet<i32>>) -> Self {
MyRef(PhantomData, target)
}
fn get(&mut self) -> &mut Cell<HashSet<i32>> {
unsafe { &mut *self.1 }
}
}
fn captures_phantom(xs: Vec<i32>, mut ys: Cell<HashSet<i32>>) {
let mut ys_ref = MyRef::new(&mut ys);
if xs
.iter()
.map({
let mut ys_ref = ys_ref.clone();
move |x| ys_ref.get().get_mut().remove(x)
})
.collect::<Vec<_>>()
.contains(&true)
{
todo!()
}
}
}
pub fn issue8055(v: impl IntoIterator<Item = i32>) -> Result<impl Iterator<Item = i32>, usize> {
let mut zeros = 0;
let res: Vec<_> = v
.into_iter()
.filter(|i| {
if *i == 0 {
zeros += 1
};
*i != 0
})
.collect();
if zeros != 0 {
return Err(zeros);
}
Ok(res.into_iter())
}
mod issue8055_regression {
struct Foo<T> {
inner: T,
marker: core::marker::PhantomData<Self>,
}
impl<T: Iterator> Iterator for Foo<T> {
type Item = T::Item;
fn next(&mut self) -> Option<Self::Item> {
self.inner.next()
}
}
fn foo() {
Foo {
inner: [].iter(),
marker: core::marker::PhantomData,
}
.collect::<Vec<&i32>>()
.len();
}
}
|
