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|
#![deny(unreachable_patterns)]
// We wrap patterns in a tuple because top-level or-patterns were special-cased.
#[rustfmt::skip]
fn main() {
match (0u8,) {
(1 | 2,) => {}
(1,) => {} //~ ERROR unreachable pattern
_ => {}
}
match (0u8,) {
(1 | 2,) => {}
(2,) => {} //~ ERROR unreachable pattern
_ => {}
}
match (0u8,) {
(1,) => {}
(2,) => {}
(1 | 2,) => {} //~ ERROR unreachable pattern
_ => {}
}
match (0u8, 0u8) {
(1 | 2, 3 | 4) => {}
(1, 3) => {} //~ ERROR unreachable pattern
(1, 4) => {} //~ ERROR unreachable pattern
(2, 4) => {} //~ ERROR unreachable pattern
(2 | 1, 4) => {} //~ ERROR unreachable pattern
(1, 5 | 6) => {}
(1, 4 | 5) => {} //~ ERROR unreachable pattern
_ => {}
}
match (0u8, 0u8, 0u8) {
(0, 0, 0) => {}
(0, 0 | 1, 0) => {} //~ ERROR unreachable pattern
_ => {}
}
match (true, true) {
(false | true, false | true) => (),
}
match (Some(0u8),) {
(None | Some(1 | 2),) => {}
(Some(1),) => {} //~ ERROR unreachable pattern
(None,) => {} //~ ERROR unreachable pattern
_ => {}
}
match ((0u8,),) {
((1 | 2,) | (3 | 4,),) => {}
((1..=4,),) => {} //~ ERROR unreachable pattern
_ => {}
}
match (0,) {
(1 | 1,) => {} //~ ERROR unreachable
_ => {}
}
match 0 {
(0 | 1) | 1 => {} //~ ERROR unreachable
_ => {}
}
match 0 {
// We get two errors because recursive or-pattern expansion means we don't notice the two
// errors span a whole pattern. This could be better but doesn't matter much
0 | (0 | 0) => {}
//~^ ERROR unreachable
//~| ERROR unreachable
_ => {}
}
match None {
// There is only one error that correctly points to the whole subpattern
Some(0) |
Some( //~ ERROR unreachable
0 | 0) => {}
_ => {}
}
match [0; 2] {
[0
| 0 //~ ERROR unreachable
, 0
| 0] => {} //~ ERROR unreachable
_ => {}
}
match (true, 0) {
(true, 0 | 0) => {} //~ ERROR unreachable
(_, 0 | 0) => {} //~ ERROR unreachable
_ => {}
}
match &[][..] {
[0] => {}
[0, _] => {}
[0, _, _] => {}
[1, ..] => {}
[1 //~ ERROR unreachable
| 2, ..] => {}
_ => {}
}
match &[][..] {
[true] => {}
[true | false, ..] => {}
_ => {}
}
match &[][..] {
[false] => {}
[true, ..] => {}
[true //~ ERROR unreachable
| false, ..] => {}
_ => {}
}
match (true, None) {
(true, Some(_)) => {}
(false, Some(true)) => {}
(true | false, None | Some(true //~ ERROR unreachable
| false)) => {}
}
macro_rules! t_or_f {
() => {
(true //~ ERROR unreachable
| false)
};
}
match (true, None) {
(true, Some(_)) => {}
(false, Some(true)) => {}
(true | false, None | Some(t_or_f!())) => {}
}
match Some(0) {
Some(0) => {}
Some(0 //~ ERROR unreachable
| 1) => {}
_ => {}
}
// A subpattern that is only unreachable in one branch is overall reachable.
match (true, true) {
(true, true) => {}
(false | true, false | true) => {}
}
match (true, true) {
(true, true) => {}
(false, false) => {}
(false | true, false | true) => {}
}
// https://github.com/rust-lang/rust/issues/76836
match None {
Some(false) => {}
None | Some(true
| false) => {} //~ ERROR unreachable
}
// A subpattern that is unreachable in all branches is overall unreachable.
match (true, true) {
(false, true) => {}
(true, true) => {}
(false | true, false
| true) => {} //~ ERROR unreachable
}
match (true, true) {
(true, false) => {}
(true, true) => {}
(false
| true, //~ ERROR unreachable
false | true) => {}
}
match (true, true) {
(x, y)
| (y, x) => {} //~ ERROR unreachable
}
}
fn unreachable_in_param((_ | (_, _)): (bool, bool)) {}
//~^ ERROR unreachable
fn unreachable_in_binding() {
let bool_pair = (true, true);
let bool_option = Some(true);
let (_ | (_, _)) = bool_pair;
//~^ ERROR unreachable
for (_ | (_, _)) in [bool_pair] {}
//~^ ERROR unreachable
let (Some(_) | Some(true)) = bool_option else { return };
//~^ ERROR unreachable
if let Some(_) | Some(true) = bool_option {}
//~^ ERROR unreachable
while let Some(_) | Some(true) = bool_option {}
//~^ ERROR unreachable
}
|
