rust-clippy/tests/ui/infallible_destructuring_match.rs
2020-04-16 14:57:12 +02:00

118 lines
2.2 KiB
Rust

// run-rustfix
#![feature(exhaustive_patterns, never_type)]
#![allow(dead_code, unreachable_code, unused_variables)]
#![allow(clippy::let_and_return)]
enum SingleVariantEnum {
Variant(i32),
}
struct TupleStruct(i32);
enum EmptyEnum {}
macro_rules! match_enum {
($param:expr) => {
let data = match $param {
SingleVariantEnum::Variant(i) => i,
};
};
}
fn infallible_destructuring_match_enum() {
let wrapper = SingleVariantEnum::Variant(0);
// This should lint!
let data = match wrapper {
SingleVariantEnum::Variant(i) => i,
};
// This shouldn't (inside macro)
match_enum!(wrapper);
// This shouldn't!
let data = match wrapper {
SingleVariantEnum::Variant(_) => -1,
};
// Neither should this!
let data = match wrapper {
SingleVariantEnum::Variant(i) => -1,
};
let SingleVariantEnum::Variant(data) = wrapper;
}
macro_rules! match_struct {
($param:expr) => {
let data = match $param {
TupleStruct(i) => i,
};
};
}
fn infallible_destructuring_match_struct() {
let wrapper = TupleStruct(0);
// This should lint!
let data = match wrapper {
TupleStruct(i) => i,
};
// This shouldn't (inside macro)
match_struct!(wrapper);
// This shouldn't!
let data = match wrapper {
TupleStruct(_) => -1,
};
// Neither should this!
let data = match wrapper {
TupleStruct(i) => -1,
};
let TupleStruct(data) = wrapper;
}
macro_rules! match_never_enum {
($param:expr) => {
let data = match $param {
Ok(i) => i,
};
};
}
fn never_enum() {
let wrapper: Result<i32, !> = Ok(23);
// This should lint!
let data = match wrapper {
Ok(i) => i,
};
// This shouldn't (inside macro)
match_never_enum!(wrapper);
// This shouldn't!
let data = match wrapper {
Ok(_) => -1,
};
// Neither should this!
let data = match wrapper {
Ok(i) => -1,
};
let Ok(data) = wrapper;
}
impl EmptyEnum {
fn match_on(&self) -> ! {
// The lint shouldn't pick this up, as `let` won't work here!
let data = match *self {};
data
}
}
fn main() {}