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|
#![feature(try_blocks)]
#![allow(
clippy::eq_op,
clippy::single_match,
unused_assignments,
unused_variables,
clippy::while_immutable_condition
)]
//@no-rustfix
fn test1() {
let mut x = 0;
loop {
//~^ never_loop
// clippy::never_loop
x += 1;
if x == 1 {
return;
}
break;
}
}
fn test2() {
let mut x = 0;
loop {
x += 1;
if x == 1 {
break;
}
}
}
fn test3() {
let mut x = 0;
loop {
//~^ never_loop
// never loops
x += 1;
break;
}
}
fn test4() {
let mut x = 1;
loop {
x += 1;
match x {
5 => return,
_ => (),
}
}
}
fn test5() {
let i = 0;
loop {
//~^ never_loop
// never loops
while i == 0 {
//~^ never_loop
// never loops
break;
}
return;
}
}
fn test6() {
let mut x = 0;
'outer: loop {
x += 1;
loop {
//~^ never_loop
// never loops
if x == 5 {
break;
}
continue 'outer;
}
return;
}
}
fn test7() {
let mut x = 0;
loop {
x += 1;
match x {
1 => continue,
_ => (),
}
return;
}
}
fn test8() {
let mut x = 0;
loop {
x += 1;
match x {
5 => return,
_ => continue,
}
}
}
fn test9() {
let x = Some(1);
while let Some(y) = x {
//~^ never_loop
// never loops
return;
}
}
fn test10() {
for x in 0..10 {
//~^ never_loop
// never loops
match x {
1 => break,
_ => return,
}
}
}
fn test11<F: FnMut() -> i32>(mut f: F) {
loop {
return match f() {
1 => continue,
_ => (),
};
}
}
pub fn test12(a: bool, b: bool) {
'label: loop {
loop {
if a {
continue 'label;
}
if b {
break;
}
}
break;
}
}
pub fn test13() {
let mut a = true;
loop {
// infinite loop
while a {
if true {
a = false;
continue;
}
return;
}
}
}
pub fn test14() {
let mut a = true;
'outer: while a {
//~^ never_loop
// never loops
while a {
if a {
a = false;
continue;
}
}
break 'outer;
}
}
// Issue #1991: the outer loop should not warn.
pub fn test15() {
'label: loop {
while false {
//~^ never_loop
break 'label;
}
}
}
// Issue #4058: `continue` in `break` expression
pub fn test16() {
let mut n = 1;
loop {
break if n != 5 {
n += 1;
continue;
};
}
}
// Issue #9001: `continue` in struct expression fields
pub fn test17() {
struct Foo {
f: (),
}
let mut n = 0;
let _ = loop {
break Foo {
f: if n < 5 {
n += 1;
continue;
},
};
};
}
// Issue #9356: `continue` in else branch of let..else
pub fn test18() {
let x = Some(0);
let y = 0;
// might loop
let _ = loop {
let Some(x) = x else {
if y > 0 {
continue;
} else {
return;
}
};
break x;
};
// never loops
let _ = loop {
//~^ never_loop
let Some(x) = x else {
return;
};
break x;
};
}
// Issue #9831: unconditional break to internal labeled block
pub fn test19() {
fn thing(iter: impl Iterator) {
for _ in iter {
'b: {
break 'b;
}
}
}
}
pub fn test20() {
'a: loop {
//~^ never_loop
'b: {
break 'b 'c: {
break 'a;
//~^ diverging_sub_expression
};
}
}
}
pub fn test21() {
loop {
'a: {
{}
break 'a;
}
}
}
// Issue 10304: code after break from block was not considered
// unreachable code and was considered for further analysis of
// whether the loop would ever be executed or not.
pub fn test22() {
for _ in 0..10 {
'block: {
break 'block;
return;
}
println!("looped");
}
}
pub fn test23() {
for _ in 0..10 {
'block: {
for _ in 0..20 {
//~^ never_loop
break 'block;
}
}
println!("looped");
}
}
pub fn test24() {
'a: for _ in 0..10 {
'b: {
let x = Some(1);
match x {
None => break 'a,
Some(_) => break 'b,
}
}
}
}
// Do not lint, we can evaluate `true` to always succeed thus can short-circuit before the `return`
pub fn test25() {
loop {
'label: {
if const { true } {
break 'label;
}
return;
}
}
}
pub fn test26() {
loop {
'label: {
if 1 == 1 {
break 'label;
}
return;
}
}
}
pub fn test27() {
loop {
'label: {
let x = true;
if x {
break 'label;
}
return;
}
}
}
// issue 11004
pub fn test29() {
loop {
'label: {
if true {
break 'label;
}
return;
}
}
}
pub fn test30() {
'a: loop {
'b: {
for j in 0..2 {
if j == 1 {
break 'b;
}
}
break 'a;
}
}
}
pub fn test31(b: bool) {
'a: loop {
'b: {
'c: loop {
//~^ never_loop
if b { break 'c } else { break 'b }
}
continue 'a;
}
break 'a;
}
}
pub fn test32() {
loop {
//~^ never_loop
panic!("oh no");
}
loop {
//~^ never_loop
unimplemented!("not yet");
}
loop {
// no error
todo!("maybe later");
}
}
pub fn issue12205() -> Option<()> {
loop {
let _: Option<_> = try {
None?;
return Some(());
};
}
}
fn stmt_after_return() {
for v in 0..10 {
//~^ never_loop
break;
println!("{v}");
}
}
fn loop_label() {
'outer: for v in 0..10 {
//~^ never_loop
loop {
//~^ never_loop
break 'outer;
}
return;
}
for v in 0..10 {
//~^ never_loop
'inner: loop {
//~^ never_loop
break 'inner;
}
return;
}
}
fn main() {
test1();
test2();
test3();
test4();
test5();
test6();
test7();
test8();
test9();
test10();
test11(|| 0);
test12(true, false);
test13();
test14();
}
fn issue15059() {
'a: for _ in 0..1 {
//~^ never_loop
break 'a;
}
let mut b = 1;
'a: for i in 0..1 {
//~^ never_loop
match i {
0 => {
b *= 2;
break 'a;
},
x => {
b += x;
break 'a;
},
}
}
#[allow(clippy::unused_unit)]
for v in 0..10 {
//~^ never_loop
break;
println!("{v}");
// This is comment and should be kept
println!("This is a comment");
()
}
}
fn issue15350() {
'bar: for _ in 0..100 {
//~^ never_loop
loop {
//~^ never_loop
println!("This will still run");
break 'bar;
}
}
'foo: for _ in 0..100 {
//~^ never_loop
loop {
//~^ never_loop
println!("This will still run");
loop {
//~^ never_loop
println!("This will still run");
break 'foo;
}
}
}
}
|
