rust-clippy/tests/ui/from_iter_instead_of_collect.rs

60 lines
1.6 KiB
Rust

#![warn(clippy::from_iter_instead_of_collect)]
#![allow(unused_imports)]
#![allow(clippy::useless_vec)]
use std::collections::{BTreeMap, BTreeSet, HashMap, VecDeque};
struct Foo(Vec<bool>);
impl FromIterator<bool> for Foo {
fn from_iter<T: IntoIterator<Item = bool>>(_: T) -> Self {
todo!()
}
}
impl<'a> FromIterator<&'a bool> for Foo {
fn from_iter<T: IntoIterator<Item = &'a bool>>(iter: T) -> Self {
<Self as FromIterator<bool>>::from_iter(iter.into_iter().copied())
}
}
fn main() {
let iter_expr = std::iter::repeat(5).take(5);
let _ = Vec::from_iter(iter_expr);
let _ = HashMap::<usize, &i8>::from_iter(vec![5, 5, 5, 5].iter().enumerate());
Vec::from_iter(vec![42u32]);
let a = vec![0, 1, 2];
assert_eq!(a, Vec::from_iter(0..3));
assert_eq!(a, Vec::<i32>::from_iter(0..3));
let mut b = VecDeque::from_iter(0..3);
b.push_back(4);
let mut b = VecDeque::<i32>::from_iter(0..3);
b.push_back(4);
{
use std::collections;
let mut b = collections::VecDeque::<i32>::from_iter(0..3);
b.push_back(4);
}
let values = [(0, 'a'), (1, 'b'), (2, 'c'), (3, 'd')];
let bm = BTreeMap::from_iter(values.iter().cloned());
let mut bar = BTreeMap::from_iter(bm.range(0..2));
bar.insert(&4, &'e');
let mut bts = BTreeSet::from_iter(0..3);
bts.insert(2);
{
use std::collections;
let _ = collections::BTreeSet::from_iter(0..3);
let _ = collections::BTreeSet::<u32>::from_iter(0..3);
}
for _i in Vec::from_iter([1, 2, 3].iter()) {}
for _i in Vec::<&i32>::from_iter([1, 2, 3].iter()) {}
}