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#![feature(exhaustive_patterns, never_type)]
#![allow(dead_code, unreachable_code, unused_variables)]
#![allow(clippy::let_and_return, clippy::uninhabited_references)]
enum SingleVariantEnum {
Variant(i32),
}
struct TupleStruct(i32);
struct NonCopy;
struct TupleStructWithNonCopy(NonCopy);
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 $param {
TupleStruct(i) => i,
};
};
}
fn infallible_destructuring_match_struct() {
let wrapper = TupleStruct(0);
// This should lint!
let data = match wrapper {
TupleStruct(i) => i,
};
// This shouldn't (inside macro)
match_struct!(wrapper);
// This shouldn't!
let data = match wrapper {
TupleStruct(_) => -1,
};
// Neither should this!
let data = match wrapper {
TupleStruct(i) => -1,
};
let TupleStruct(data) = wrapper;
}
fn infallible_destructuring_match_struct_with_noncopy() {
let wrapper = TupleStructWithNonCopy(NonCopy);
// This should lint! (keeping `ref` in the suggestion)
let data = match wrapper {
TupleStructWithNonCopy(ref n) => n,
};
let TupleStructWithNonCopy(ref data) = wrapper;
}
macro_rules! match_never_enum {
($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() {}
|
