#![feature(plugin, step_by, inclusive_range_syntax)]
#![plugin(clippy)]
use std::collections::*;
static STATIC: [usize; 4] = [ 0, 1, 8, 16 ];
const CONST: [usize; 4] = [ 0, 1, 8, 16 ];
#[deny(clippy)]
fn for_loop_over_option_and_result() {
let option = Some(1);
let result = option.ok_or("x not found");
let v = vec![0,1,2];
// check FOR_LOOP_OVER_OPTION lint
for x in option {
//~^ ERROR for loop over `option`, which is an `Option`.
//~| HELP consider replacing `for x in option` with `if let Some(x) = option`
println!("{}", x);
}
// check FOR_LOOP_OVER_RESULT lint
for x in result {
//~^ ERROR for loop over `result`, which is a `Result`.
//~| HELP consider replacing `for x in result` with `if let Ok(x) = result`
println!("{}", x);
}
for x in option.ok_or("x not found") {
//~^ ERROR for loop over `option.ok_or("x not found")`, which is a `Result`.
//~| HELP consider replacing `for x in option.ok_or("x not found")` with `if let Ok(x) = option.ok_or("x not found")`
println!("{}", x);
}
// make sure LOOP_OVER_NEXT lint takes precedence when next() is the last call in the chain
for x in v.iter().next() {
//~^ ERROR you are iterating over `Iterator::next()` which is an Option
println!("{}", x);
}
// make sure we lint when next() is not the last call in the chain
for x in v.iter().next().and(Some(0)) {
//~^ ERROR for loop over `v.iter().next().and(Some(0))`, which is an `Option`
//~| HELP consider replacing `for x in v.iter().next().and(Some(0))` with `if let Some(x) = v.iter().next().and(Some(0))`
println!("{}", x);
}
for x in v.iter().next().ok_or("x not found") {
//~^ ERROR for loop over `v.iter().next().ok_or("x not found")`, which is a `Result`
//~| HELP consider replacing `for x in v.iter().next().ok_or("x not found")` with `if let Ok(x) = v.iter().next().ok_or("x not found")`
println!("{}", x);
}
// check for false positives
// for loop false positive
for x in v {
println!("{}", x);
}
// while let false positive for Option
while let Some(x) = option {
println!("{}", x);
break;
}
// while let false positive for Result
while let Ok(x) = result {
println!("{}", x);
break;
}
}
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()
}
}
#[deny(needless_range_loop, explicit_iter_loop, iter_next_loop, reverse_range_loop, explicit_counter_loop)]
#[deny(unused_collect)]
#[allow(linkedlist, shadow_unrelated, unnecessary_mut_passed, cyclomatic_complexity, similar_names)]
#[allow(many_single_char_names)]
fn main() {
const MAX_LEN: usize = 42;
let mut vec = vec![1, 2, 3, 4];
let vec2 = vec![1, 2, 3, 4];
for i in 0..vec.len() {
//~^ ERROR `i` is only used to index `vec`. Consider using `for item in &vec`
println!("{}", vec[i]);
}
// ICE #746
for j in 0..4 {
//~^ ERROR `j` is only used to index `STATIC`
println!("{:?}", STATIC[j]);
}
for j in 0..4 {
//~^ ERROR `j` is only used to index `CONST`
println!("{:?}", CONST[j]);
}
for i in 0..vec.len() {
//~^ ERROR `i` is used to index `vec`. Consider using `for (i, item) in vec.iter().enumerate()`
println!("{} {}", vec[i], i);
}
for i in 0..vec.len() { // not an error, indexing more than one variable
println!("{} {}", vec[i], vec2[i]);
}
for i in 0..vec.len() {
//~^ ERROR `i` is only used to index `vec2`. Consider using `for item in vec2.iter().take(vec.len())`
println!("{}", vec2[i]);
}
for i in 5..vec.len() {
//~^ ERROR `i` is only used to index `vec`. Consider using `for item in vec.iter().skip(5)`
println!("{}", vec[i]);
}
for i in 0..MAX_LEN {
//~^ ERROR `i` is only used to index `vec`. Consider using `for item in vec.iter().take(MAX_LEN)`
println!("{}", vec[i]);
}
for i in 0...MAX_LEN {
//~^ ERROR `i` is only used to index `vec`. Consider using `for item in vec.iter().take(MAX_LEN)`
println!("{}", vec[i]);
}
for i in 5..10 {
//~^ ERROR `i` is only used to index `vec`. Consider using `for item in vec.iter().take(10).skip(5)`
println!("{}", vec[i]);
}
for i in 5...10 {
//~^ ERROR `i` is only used to index `vec`. Consider using `for item in vec.iter().take(10).skip(5)`
println!("{}", vec[i]);
}
for i in 5..vec.len() {
//~^ ERROR `i` is used to index `vec`. Consider using `for (i, item) in vec.iter().enumerate().skip(5)`
println!("{} {}", vec[i], i);
}
for i in 5..10 {
//~^ ERROR `i` is used to index `vec`. Consider using `for (i, item) in vec.iter().enumerate().take(10).skip(5)`
println!("{} {}", vec[i], i);
}
for i in 10..0 {
//~^ERROR this range is empty so this for loop will never run
//~|HELP consider
//~|SUGGESTION (0..10).rev()
println!("{}", i);
}
for i in 10...0 {
//~^ERROR this range is empty so this for loop will never run
//~|HELP consider
//~|SUGGESTION (0..10).rev()
println!("{}", i);
}
for i in MAX_LEN..0 { //~ERROR this range is empty so this for loop will never run
//~|HELP consider
//~|SUGGESTION (0..MAX_LEN).rev()
println!("{}", i);
}
for i in 5..5 { //~ERROR this range is empty so this for loop will never run
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 { //~ERROR this range is empty so this for loop will never run
println!("{}", i);
}
for i in (5+2)..(3-1) { //~ERROR this range is empty so this for loop will never run
println!("{}", i);
}
for i in (5+2)..(8-1) { //~ERROR this range is empty so this for loop will never run
println!("{}", i);
}
for i in (2*2)..(2*3) { // no error, 4..6 is fine
println!("{}", i);
}
for i in (10..8).step_by(-1) {
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 i in (10..0).map(|x| x * 2) {
println!("{}", i);
}*/
for _v in vec.iter() { } //~ERROR it is more idiomatic to loop over `&vec`
for _v in vec.iter_mut() { } //~ERROR it is more idiomatic to loop over `&mut vec`
for _v in &vec { } // these are fine
for _v in &mut vec { } // these are fine
for _v in [1, 2, 3].iter() { } //~ERROR it is more idiomatic to loop over `&[
for _v in (&mut [1, 2, 3]).iter() { } // no error
for _v in [0; 32].iter() {} //~ERROR it is more idiomatic to loop over `&[
for _v in [0; 33].iter() {} // no error
let ll: LinkedList<()> = LinkedList::new();
for _v in ll.iter() { } //~ERROR it is more idiomatic to loop over `&ll`
let vd: VecDeque<()> = VecDeque::new();
for _v in vd.iter() { } //~ERROR it is more idiomatic to loop over `&vd`
let bh: BinaryHeap<()> = BinaryHeap::new();
for _v in bh.iter() { } //~ERROR it is more idiomatic to loop over `&bh`
let hm: HashMap<(), ()> = HashMap::new();
for _v in hm.iter() { } //~ERROR it is more idiomatic to loop over `&hm`
let bt: BTreeMap<(), ()> = BTreeMap::new();
for _v in bt.iter() { } //~ERROR it is more idiomatic to loop over `&bt`
let hs: HashSet<()> = HashSet::new();
for _v in hs.iter() { } //~ERROR it is more idiomatic to loop over `&hs`
let bs: BTreeSet<()> = BTreeSet::new();
for _v in bs.iter() { } //~ERROR it is more idiomatic to loop over `&bs`
for _v in vec.iter().next() { } //~ERROR you are iterating over `Iterator::next()`
let u = Unrelated(vec![]);
for _v in u.next() { } // no error
for _v in u.iter() { } // no error
let mut out = vec![];
vec.iter().map(|x| out.push(x)).collect::<Vec<_>>(); //~ERROR you are collect()ing an iterator
let _y = vec.iter().map(|x| out.push(x)).collect::<Vec<_>>(); // this is fine
// Loop with explicit counter variable
let mut _index = 0;
for _v in &vec { _index += 1 } //~ERROR the variable `_index` is used as a loop counter
let mut _index = 1;
_index = 0;
for _v in &vec { _index += 1 } //~ERROR the variable `_index` is used as a loop counter
// 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);
for_loop_over_option_and_result();
let m : HashMap<u64, u64> = HashMap::new();
for (_, v) in &m {
//~^ you seem to want to iterate on a map's values
//~| HELP use the corresponding method
//~| SUGGESTION for v in m.values()
let _v = v;
}
let mut m : HashMap<u64, u64> = HashMap::new();
for (_, v) in &mut m {
// Ok, there is no values_mut method or equivalent
let _v = v;
}
let rm = &m;
for (k, _value) in rm {
//~^ you seem to want to iterate on a map's keys
//~| HELP use the corresponding method
//~| SUGGESTION for k in rm.keys()
let _k = k;
}
test_for_kv_map();
}
#[allow(used_underscore_binding)]
fn test_for_kv_map() {
let m : HashMap<u64, u64> = HashMap::new();
// No error, _value is actually used
for (k, _value) in &m {
let _ = _value;
let _k = k;
}
}