rust-clippy/tests/ui/iter_overeager_cloned.fixed
lengyijun fc061890d6 [iter_overeager_cloned]: detect .cloned().filter() and .cloned().find()
Key idea:
```
// before
iter.cloned().filter(|x| unimplemented!() )
// after
iter.filter(|&x| unimplemented!() ).cloned()

// before
iter.cloned().filter( foo )
// after
iter.filter(|&x| foo(x) ).cloned()
```
2023-08-14 09:13:01 +08:00

84 lines
2.5 KiB
Rust

#![warn(clippy::iter_overeager_cloned, clippy::redundant_clone, clippy::filter_next)]
#![allow(dead_code, clippy::let_unit_value, clippy::useless_vec)]
fn main() {
let vec = vec!["1".to_string(), "2".to_string(), "3".to_string()];
let _: Option<String> = vec.iter().last().cloned();
let _: Option<String> = vec.iter().chain(vec.iter()).next().cloned();
let _: usize = vec.iter().filter(|x| x == &"2").count();
let _: Vec<_> = vec.iter().take(2).cloned().collect();
let _: Vec<_> = vec.iter().skip(2).cloned().collect();
let _ = vec.iter().filter(|x| x == &"2").nth(2).cloned();
let _ = [Some(Some("str".to_string())), Some(Some("str".to_string()))]
.iter()
.flatten().cloned();
let _ = vec.iter().filter(|&x| x.starts_with('2')).cloned();
let _ = vec.iter().find(|&x| x == "2").cloned();
{
let f = |x: &String| x.starts_with('2');
let _ = vec.iter().filter(|&x| f(x)).cloned();
let _ = vec.iter().find(|&x| f(x)).cloned();
}
{
let vec: Vec<(String, String)> = vec![];
let f = move |x: &(String, String)| x.0.starts_with('2');
let _ = vec.iter().filter(|&x| f(x)).cloned();
let _ = vec.iter().find(|&x| f(x)).cloned();
}
fn test_move<'a>(
iter: impl Iterator<Item = &'a (&'a u32, String)> + 'a,
target: String,
) -> impl Iterator<Item = (&'a u32, String)> + 'a {
iter.filter(move |&(&a, b)| a == 1 && b == &target).cloned()
}
{
#[derive(Clone)]
struct S<'a> {
a: &'a u32,
b: String,
}
fn bar<'a>(iter: impl Iterator<Item = &'a S<'a>> + 'a, target: String) -> impl Iterator<Item = S<'a>> + 'a {
iter.filter(move |&S { a, b }| **a == 1 && b == &target).cloned()
}
}
// Not implemented yet
let _ = vec.iter().cloned().map(|x| x.len());
// This would fail if changed.
let _ = vec.iter().cloned().map(|x| x + "2");
// Not implemented yet
let _ = vec.iter().cloned().for_each(|x| assert!(!x.is_empty()));
// Not implemented yet
let _ = vec.iter().cloned().all(|x| x.len() == 1);
// Not implemented yet
let _ = vec.iter().cloned().any(|x| x.len() == 1);
// Should probably stay as it is.
let _ = [0, 1, 2, 3, 4].iter().cloned().take(10);
// `&Range<_>` doesn't implement `IntoIterator`
let _ = [0..1, 2..5].iter().cloned().flatten();
}
// #8527
fn cloned_flatten(x: Option<&Option<String>>) -> Option<String> {
x.cloned().flatten()
}