rust/tests/ui/for_loop_fixable.rs
2020-04-08 08:37:20 -07:00

338 lines
6.7 KiB
Rust

// run-rustfix
#![allow(dead_code, unused)]
use std::collections::*;
#[warn(clippy::all)]
struct Unrelated(Vec<u8>);
impl Unrelated {
fn next(&self) -> std::slice::Iter<u8> {
self.0.iter()
}
fn iter(&self) -> std::slice::Iter<u8> {
self.0.iter()
}
}
#[warn(
clippy::needless_range_loop,
clippy::explicit_iter_loop,
clippy::explicit_into_iter_loop,
clippy::iter_next_loop,
clippy::reverse_range_loop,
clippy::for_kv_map
)]
#[allow(
clippy::linkedlist,
clippy::shadow_unrelated,
clippy::unnecessary_mut_passed,
clippy::similar_names
)]
#[allow(clippy::many_single_char_names, unused_variables)]
fn main() {
const MAX_LEN: usize = 42;
let mut vec = vec![1, 2, 3, 4];
for i in 10..0 {
println!("{}", i);
}
for i in 10..=0 {
println!("{}", i);
}
for i in MAX_LEN..0 {
println!("{}", i);
}
for i in 5..=5 {
// not an error, this is the range with only one element “5”
println!("{}", i);
}
for i in 0..10 {
// not an error, the start index is less than the end index
println!("{}", i);
}
for i in -10..0 {
// not an error
println!("{}", i);
}
for i in (10..0).map(|x| x * 2) {
// not an error, it can't be known what arbitrary methods do to a range
println!("{}", i);
}
// testing that the empty range lint folds constants
for i in 10..5 + 4 {
println!("{}", i);
}
for i in (5 + 2)..(3 - 1) {
println!("{}", i);
}
for i in (2 * 2)..(2 * 3) {
// no error, 4..6 is fine
println!("{}", i);
}
let x = 42;
for i in x..10 {
// no error, not constant-foldable
println!("{}", i);
}
// See #601
for i in 0..10 {
// no error, id_col does not exist outside the loop
let mut id_col = vec![0f64; 10];
id_col[i] = 1f64;
}
for _v in vec.iter() {}
for _v in vec.iter_mut() {}
let out_vec = vec![1, 2, 3];
for _v in out_vec.into_iter() {}
for _v in &vec {} // these are fine
for _v in &mut vec {} // these are fine
for _v in [1, 2, 3].iter() {}
for _v in (&mut [1, 2, 3]).iter() {} // no error
for _v in [0; 32].iter() {}
for _v in [0; 33].iter() {} // no error
let ll: LinkedList<()> = LinkedList::new();
for _v in ll.iter() {}
let vd: VecDeque<()> = VecDeque::new();
for _v in vd.iter() {}
let bh: BinaryHeap<()> = BinaryHeap::new();
for _v in bh.iter() {}
let hm: HashMap<(), ()> = HashMap::new();
for _v in hm.iter() {}
let bt: BTreeMap<(), ()> = BTreeMap::new();
for _v in bt.iter() {}
let hs: HashSet<()> = HashSet::new();
for _v in hs.iter() {}
let bs: BTreeSet<()> = BTreeSet::new();
for _v in bs.iter() {}
let u = Unrelated(vec![]);
for _v in u.next() {} // no error
for _v in u.iter() {} // no error
let mut out = vec![];
vec.iter().cloned().map(|x| out.push(x)).collect::<Vec<_>>();
let _y = vec.iter().cloned().map(|x| out.push(x)).collect::<Vec<_>>(); // this is fine
// Loop with explicit counter variable
// Potential false positives
let mut _index = 0;
_index = 1;
for _v in &vec {
_index += 1
}
let mut _index = 0;
_index += 1;
for _v in &vec {
_index += 1
}
let mut _index = 0;
if true {
_index = 1
}
for _v in &vec {
_index += 1
}
let mut _index = 0;
let mut _index = 1;
for _v in &vec {
_index += 1
}
let mut _index = 0;
for _v in &vec {
_index += 1;
_index += 1
}
let mut _index = 0;
for _v in &vec {
_index *= 2;
_index += 1
}
let mut _index = 0;
for _v in &vec {
_index = 1;
_index += 1
}
let mut _index = 0;
for _v in &vec {
let mut _index = 0;
_index += 1
}
let mut _index = 0;
for _v in &vec {
_index += 1;
_index = 0;
}
let mut _index = 0;
for _v in &vec {
for _x in 0..1 {
_index += 1;
}
_index += 1
}
let mut _index = 0;
for x in &vec {
if *x == 1 {
_index += 1
}
}
let mut _index = 0;
if true {
_index = 1
};
for _v in &vec {
_index += 1
}
let mut _index = 1;
if false {
_index = 0
};
for _v in &vec {
_index += 1
}
let mut index = 0;
{
let mut _x = &mut index;
}
for _v in &vec {
_index += 1
}
let mut index = 0;
for _v in &vec {
index += 1
}
println!("index: {}", index);
fn f<T>(_: &T, _: &T) -> bool {
unimplemented!()
}
fn g<T>(_: &mut [T], _: usize, _: usize) {
unimplemented!()
}
for i in 1..vec.len() {
if f(&vec[i - 1], &vec[i]) {
g(&mut vec, i - 1, i);
}
}
for mid in 1..vec.len() {
let (_, _) = vec.split_at(mid);
}
}
fn partition<T: PartialOrd + Send>(v: &mut [T]) -> usize {
let pivot = v.len() - 1;
let mut i = 0;
for j in 0..pivot {
if v[j] <= v[pivot] {
v.swap(i, j);
i += 1;
}
}
v.swap(i, pivot);
i
}
#[warn(clippy::needless_range_loop)]
pub fn manual_copy_same_destination(dst: &mut [i32], d: usize, s: usize) {
// Same source and destination - don't trigger lint
for i in 0..dst.len() {
dst[d + i] = dst[s + i];
}
}
mod issue_2496 {
pub trait Handle {
fn new_for_index(index: usize) -> Self;
fn index(&self) -> usize;
}
pub fn test<H: Handle>() -> H {
for x in 0..5 {
let next_handle = H::new_for_index(x);
println!("{}", next_handle.index());
}
unimplemented!()
}
}
// explicit_into_iter_loop bad suggestions
#[warn(clippy::explicit_into_iter_loop, clippy::explicit_iter_loop)]
mod issue_4958 {
fn takes_iterator<T>(iterator: &T)
where
for<'a> &'a T: IntoIterator<Item = &'a String>,
{
for i in iterator.into_iter() {
println!("{}", i);
}
}
struct T;
impl IntoIterator for &T {
type Item = ();
type IntoIter = std::vec::IntoIter<Self::Item>;
fn into_iter(self) -> Self::IntoIter {
vec![].into_iter()
}
}
fn more_tests() {
let t = T;
let r = &t;
let rr = &&t;
// This case is handled by `explicit_iter_loop`. No idea why.
for _ in t.into_iter() {}
for _ in r.into_iter() {}
// No suggestion for this.
// We'd have to suggest `for _ in *rr {}` which is less clear.
for _ in rr.into_iter() {}
}
}