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|
#![warn(clippy::match_same_arms)]
#![allow(clippy::blacklisted_name)]
fn bar<T>(_: T) {}
fn foo() -> bool {
unimplemented!()
}
fn match_same_arms() {
let _ = match 42 {
42 => {
foo();
let mut a = 42 + [23].len() as i32;
if true {
a += 7;
}
a = -31 - a;
a
},
_ => {
//~ ERROR match arms have same body
foo();
let mut a = 42 + [23].len() as i32;
if true {
a += 7;
}
a = -31 - a;
a
},
};
let _ = match 42 {
42 => foo(),
51 => foo(), //~ ERROR match arms have same body
_ => true,
};
let _ = match Some(42) {
Some(_) => 24,
None => 24, //~ ERROR match arms have same body
};
let _ = match Some(42) {
Some(foo) => 24,
None => 24,
};
let _ = match Some(42) {
Some(42) => 24,
Some(a) => 24, // bindings are different
None => 0,
};
let _ = match Some(42) {
Some(a) if a > 0 => 24,
Some(a) => 24, // one arm has a guard
None => 0,
};
match (Some(42), Some(42)) {
(Some(a), None) => bar(a),
(None, Some(a)) => bar(a), //~ ERROR match arms have same body
_ => (),
}
match (Some(42), Some(42)) {
(Some(a), ..) => bar(a),
(.., Some(a)) => bar(a), //~ ERROR match arms have same body
_ => (),
}
let _ = match Some(()) {
Some(()) => 0.0,
None => -0.0,
};
match (Some(42), Some("")) {
(Some(a), None) => bar(a),
(None, Some(a)) => bar(a), // bindings have different types
_ => (),
}
let x: Result<i32, &str> = Ok(3);
// No warning because of the guard.
match x {
Ok(x) if x * x == 64 => println!("ok"),
Ok(_) => println!("ok"),
Err(_) => println!("err"),
}
// This used to be a false positive; see issue #1996.
match x {
Ok(3) => println!("ok"),
Ok(x) if x * x == 64 => println!("ok 64"),
Ok(_) => println!("ok"),
Err(_) => println!("err"),
}
match (x, Some(1i32)) {
(Ok(x), Some(_)) => println!("ok {}", x),
(Ok(_), Some(x)) => println!("ok {}", x),
_ => println!("err"),
}
// No warning; different types for `x`.
match (x, Some(1.0f64)) {
(Ok(x), Some(_)) => println!("ok {}", x),
(Ok(_), Some(x)) => println!("ok {}", x),
_ => println!("err"),
}
// False negative #2251.
match x {
Ok(_tmp) => println!("ok"),
Ok(3) => println!("ok"),
Ok(_) => println!("ok"),
Err(_) => {
unreachable!();
},
}
// False positive #1390
macro_rules! empty {
($e:expr) => {};
}
match 0 {
0 => {
empty!(0);
},
1 => {
empty!(1);
},
x => {
empty!(x);
},
};
// still lint if the tokens are the same
match 0 {
0 => {
empty!(0);
},
1 => {
empty!(0);
},
x => {
empty!(x);
},
}
match_expr_like_matches_macro_priority();
}
fn match_expr_like_matches_macro_priority() {
enum E {
A,
B,
C,
}
let x = E::A;
let _ans = match x {
E::A => false,
E::B => false,
_ => true,
};
}
fn main() {}
|
