2019-05-08 22:55:24 -05:00
|
|
|
#![warn(clippy::while_let_on_iterator)]
|
|
|
|
#![allow(clippy::never_loop, clippy::cognitive_complexity)]
|
2015-10-02 02:55:34 -05:00
|
|
|
|
2015-08-29 04:41:06 -05:00
|
|
|
fn main() {
|
2015-10-22 16:16:58 -05:00
|
|
|
let mut iter = 1..20;
|
2016-06-07 11:33:11 -05:00
|
|
|
while let Option::Some(x) = iter.next() {
|
2015-10-16 13:27:13 -05:00
|
|
|
println!("{}", x);
|
|
|
|
}
|
|
|
|
|
2015-10-22 16:16:58 -05:00
|
|
|
let mut iter = 1..20;
|
2016-06-07 11:33:11 -05:00
|
|
|
while let Some(x) = iter.next() {
|
2015-10-16 13:27:13 -05:00
|
|
|
println!("{}", x);
|
|
|
|
}
|
|
|
|
|
2015-10-22 16:16:58 -05:00
|
|
|
let mut iter = 1..20;
|
2016-06-07 11:33:11 -05:00
|
|
|
while let Some(_) = iter.next() {}
|
2017-02-08 07:58:07 -06:00
|
|
|
|
2015-10-22 16:16:58 -05:00
|
|
|
let mut iter = 1..20;
|
|
|
|
while let None = iter.next() {} // this is fine (if nonsensical)
|
2015-10-16 13:27:13 -05:00
|
|
|
|
2015-10-22 16:16:58 -05:00
|
|
|
let mut iter = 1..20;
|
2018-12-09 16:26:16 -06:00
|
|
|
if let Some(x) = iter.next() {
|
|
|
|
// also fine
|
2015-10-16 13:27:13 -05:00
|
|
|
println!("{}", x)
|
|
|
|
}
|
2015-10-19 18:04:21 -05:00
|
|
|
|
|
|
|
// the following shouldn't warn because it can't be written with a for loop
|
|
|
|
let mut iter = 1u32..20;
|
|
|
|
while let Some(x) = iter.next() {
|
|
|
|
println!("next: {:?}", iter.next())
|
|
|
|
}
|
2015-10-26 17:49:37 -05:00
|
|
|
|
|
|
|
// neither can this
|
|
|
|
let mut iter = 1u32..20;
|
|
|
|
while let Some(x) = iter.next() {
|
|
|
|
println!("next: {:?}", iter.next());
|
|
|
|
}
|
|
|
|
|
|
|
|
// or this
|
|
|
|
let mut iter = 1u32..20;
|
2018-12-09 16:26:16 -06:00
|
|
|
while let Some(x) = iter.next() {
|
|
|
|
break;
|
|
|
|
}
|
2015-10-26 17:49:37 -05:00
|
|
|
println!("Remaining iter {:?}", iter);
|
|
|
|
|
|
|
|
// or this
|
|
|
|
let mut iter = 1u32..20;
|
|
|
|
while let Some(x) = iter.next() {
|
|
|
|
iter = 1..20;
|
|
|
|
}
|
2015-08-29 04:41:06 -05:00
|
|
|
}
|
2015-10-02 02:55:34 -05:00
|
|
|
|
2016-09-16 08:45:44 -05:00
|
|
|
// Issue #1188
|
|
|
|
fn refutable() {
|
|
|
|
let a = [42, 1337];
|
|
|
|
let mut b = a.iter();
|
|
|
|
|
|
|
|
// consume all the 42s
|
2018-12-09 16:26:16 -06:00
|
|
|
while let Some(&42) = b.next() {}
|
2016-09-16 08:45:44 -05:00
|
|
|
|
|
|
|
let a = [(1, 2, 3)];
|
|
|
|
let mut b = a.iter();
|
|
|
|
|
2018-12-09 16:26:16 -06:00
|
|
|
while let Some(&(1, 2, 3)) = b.next() {}
|
2016-09-16 08:45:44 -05:00
|
|
|
|
|
|
|
let a = [Some(42)];
|
|
|
|
let mut b = a.iter();
|
|
|
|
|
2018-12-09 16:26:16 -06:00
|
|
|
while let Some(&None) = b.next() {}
|
2016-09-16 08:45:44 -05:00
|
|
|
|
|
|
|
/* This gives “refutable pattern in `for` loop binding: `&_` not covered”
|
|
|
|
for &42 in b {}
|
|
|
|
for &(1, 2, 3) in b {}
|
|
|
|
for &Option::None in b.next() {}
|
|
|
|
// */
|
2019-05-06 00:49:45 -05:00
|
|
|
}
|
2017-06-23 11:29:18 -05:00
|
|
|
|
2019-05-06 00:49:45 -05:00
|
|
|
fn nested_loops() {
|
|
|
|
let a = [42, 1337];
|
2017-06-29 19:43:52 -05:00
|
|
|
let mut y = a.iter();
|
2018-12-09 16:26:16 -06:00
|
|
|
loop {
|
|
|
|
// x is reused, so don't lint here
|
|
|
|
while let Some(v) = y.next() {}
|
2017-06-23 11:29:18 -05:00
|
|
|
}
|
|
|
|
|
2017-06-29 19:43:52 -05:00
|
|
|
let mut y = a.iter();
|
2017-06-23 11:29:18 -05:00
|
|
|
for _ in 0..2 {
|
2018-12-09 16:26:16 -06:00
|
|
|
while let Some(v) = y.next() {
|
|
|
|
// y is reused, don't lint
|
2017-07-31 17:58:26 -05:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
loop {
|
|
|
|
let mut y = a.iter();
|
2018-12-09 16:26:16 -06:00
|
|
|
while let Some(v) = y.next() {
|
|
|
|
// use a for loop here
|
2017-06-23 11:29:18 -05:00
|
|
|
}
|
|
|
|
}
|
2019-05-06 00:49:45 -05:00
|
|
|
}
|
2017-09-05 15:28:30 -05:00
|
|
|
|
2019-05-06 00:49:45 -05:00
|
|
|
fn issue1121() {
|
2018-01-29 09:52:22 -06:00
|
|
|
use std::collections::HashSet;
|
|
|
|
let mut values = HashSet::new();
|
|
|
|
values.insert(1);
|
|
|
|
|
|
|
|
while let Some(&value) = values.iter().next() {
|
|
|
|
values.remove(&value);
|
|
|
|
}
|
2019-05-06 00:49:45 -05:00
|
|
|
}
|
2018-07-28 04:51:46 -05:00
|
|
|
|
2019-05-06 00:49:45 -05:00
|
|
|
fn issue2965() {
|
2018-07-28 04:51:46 -05:00
|
|
|
// This should not cause an ICE and suggest:
|
|
|
|
//
|
|
|
|
// for _ in values.iter() {}
|
|
|
|
//
|
2019-05-06 00:49:45 -05:00
|
|
|
use std::collections::HashSet;
|
|
|
|
let mut values = HashSet::new();
|
|
|
|
values.insert(1);
|
|
|
|
|
2018-07-28 04:51:46 -05:00
|
|
|
while let Some(..) = values.iter().next() {
|
|
|
|
values.remove(&1);
|
|
|
|
}
|
2019-05-06 00:49:45 -05:00
|
|
|
}
|
2019-01-19 03:36:27 -06:00
|
|
|
|
2019-05-06 00:49:45 -05:00
|
|
|
fn issue3670() {
|
|
|
|
let array = [Some(0), None, Some(1)];
|
|
|
|
let mut iter = array.iter();
|
2019-01-19 03:36:27 -06:00
|
|
|
|
2019-05-06 00:49:45 -05:00
|
|
|
while let Some(elem) = iter.next() {
|
|
|
|
let _ = elem.or_else(|| *iter.next()?);
|
2019-01-19 03:36:27 -06:00
|
|
|
}
|
2016-09-16 08:45:44 -05:00
|
|
|
}
|