rust/tests/ui/lint/unused/issue-54538-unused-parens-lint.rs
2024-02-16 20:02:50 +00:00

129 lines
4.4 KiB
Rust

//@ run-rustfix
#![feature(box_patterns, stmt_expr_attributes, yeet_expr)]
#![allow(
dead_code,
ellipsis_inclusive_range_patterns,
irrefutable_let_patterns,
unreachable_patterns,
unused_mut,
unused_variables
)]
#![deny(unused_parens)]
fn lint_on_top_level() {
let (a) = 0; //~ ERROR unnecessary parentheses around pattern
for (a) in 0..1 {} //~ ERROR unnecessary parentheses around pattern
if let (a) = 0 {} //~ ERROR unnecessary parentheses around pattern
while let (a) = 0 {} //~ ERROR unnecessary parentheses around pattern
fn foo((a): u8) {} //~ ERROR unnecessary parentheses around pattern
let _ = |(a): u8| 0; //~ ERROR unnecessary parentheses around pattern
}
fn no_lint_attr() {
let _x = #[allow(dead_code)] (1 + 2);
}
fn no_lint_yeet() -> Result<(), ()> {
#[allow(unreachable_code)]
if (do yeet) {}
Ok(())
}
fn no_lint_ops() {
#![allow(unreachable_code, irrefutable_let_patterns)]
if ((..{}) == ..{}) {}
if (!return) {}
loop { match (() = () = () = break {}) {} }
while let () = (*&mut false |= true && return) {}
}
fn lint_break_if_not_followed_by_block() {
#![allow(unreachable_code)]
loop { if (break) {} } //~ ERROR unnecessary parentheses
loop { if (break ({ println!("hello") })) {} } //~ ERROR unnecessary parentheses
loop { if (break { println!("hello") }) {} }
}
// Don't lint in these cases (#64106).
fn or_patterns_no_lint() {
match Box::new(0) {
box (0 | 1) => {} // Should not lint as `box 0 | 1` binds as `(box 0) | 1`.
_ => {}
}
match 0 {
x @ (0 | 1) => {} // Should not lint as `x @ 0 | 1` binds as `(x @ 0) | 1`.
_ => {}
}
if let &(0 | 1) = &0 {} // Should also not lint.
if let &mut (0 | 1) = &mut 0 {} // Same.
fn foo((Ok(a) | Err(a)): Result<u8, u8>) {} // Doesn't parse if we remove parens for now.
let _ = |(Ok(a) | Err(a)): Result<u8, u8>| 1; // `|Ok(a) | Err(a)| 1` parses as bit-or.
}
fn or_patterns_will_lint() {
if let (0 | 1) = 0 {} //~ ERROR unnecessary parentheses around pattern
if let ((0 | 1),) = (0,) {} //~ ERROR unnecessary parentheses around pattern
if let [(0 | 1)] = [0] {} //~ ERROR unnecessary parentheses around pattern
if let 0 | (1 | 2) = 0 {} //~ ERROR unnecessary parentheses around pattern
struct TS(u8);
if let TS((0 | 1)) = TS(0) {} //~ ERROR unnecessary parentheses around pattern
struct NS { f: u8 }
if let NS { f: (0 | 1) } = (NS { f: 0 }) {} //~ ERROR unnecessary parentheses around pattern
}
// Don't lint on `&(mut x)` because `&mut x` means something else (#55342).
fn deref_mut_binding_no_lint() {
let &(mut x) = &0;
}
fn main() {
match 1 {
(_) => {} //~ ERROR unnecessary parentheses around pattern
(y) => {} //~ ERROR unnecessary parentheses around pattern
(ref r) => {} //~ ERROR unnecessary parentheses around pattern
(e @ 1...2) => {} //~ ERROR unnecessary parentheses around pattern
(1...2) => {} // Non ambiguous range pattern should not warn
e @ (3...4) => {} // Non ambiguous range pattern should not warn
}
match &1 {
(e @ &(1...2)) => {} //~ ERROR unnecessary parentheses around pattern
&(_) => {} //~ ERROR unnecessary parentheses around pattern
e @ &(1...2) => {} // Ambiguous range pattern should not warn
&(1...2) => {} // Ambiguous range pattern should not warn
}
match &1 {
e @ &(1...2) | e @ &(3...4) => {} // Complex ambiguous pattern should not warn
&_ => {}
}
match 1 {
(_) => {} //~ ERROR unnecessary parentheses around pattern
(y) => {} //~ ERROR unnecessary parentheses around pattern
(ref r) => {} //~ ERROR unnecessary parentheses around pattern
(e @ 1..=2) => {} //~ ERROR unnecessary parentheses around pattern
(1..=2) => {} // Non ambiguous range pattern should not warn
e @ (3..=4) => {} // Non ambiguous range pattern should not warn
}
match &1 {
(e @ &(1..=2)) => {} //~ ERROR unnecessary parentheses around pattern
&(_) => {} //~ ERROR unnecessary parentheses around pattern
e @ &(1..=2) => {} // Ambiguous range pattern should not warn
&(1..=2) => {} // Ambiguous range pattern should not warn
}
match &1 {
e @ &(1..=2) | e @ &(3..=4) => {} // Complex ambiguous pattern should not warn
&_ => {}
}
}