rust-clippy/tests/ui/option_option.rs
2020-04-01 12:15:39 -07:00

62 lines
1,022 B
Rust

#![deny(clippy::option_option)]
fn input(_: Option<Option<u8>>) {}
fn output() -> Option<Option<u8>> {
None
}
fn output_nested() -> Vec<Option<Option<u8>>> {
vec![None]
}
// The lint only generates one warning for this
fn output_nested_nested() -> Option<Option<Option<u8>>> {
None
}
struct Struct {
x: Option<Option<u8>>,
}
impl Struct {
fn struct_fn() -> Option<Option<u8>> {
None
}
}
trait Trait {
fn trait_fn() -> Option<Option<u8>>;
}
enum Enum {
Tuple(Option<Option<u8>>),
Struct { x: Option<Option<u8>> },
}
// The lint allows this
type OptionOption = Option<Option<u32>>;
// The lint allows this
fn output_type_alias() -> OptionOption {
None
}
// The line allows this
impl Trait for Struct {
fn trait_fn() -> Option<Option<u8>> {
None
}
}
fn main() {
input(None);
output();
output_nested();
// The lint allows this
let local: Option<Option<u8>> = None;
// The lint allows this
let expr = Some(Some(true));
}