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#![deny(clippy::option_option)]
#![allow(clippy::unnecessary_wraps)]
const C: Option<Option<i32>> = None;
static S: Option<Option<i32>> = None;
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));
}
extern crate serde;
mod issue_4298 {
use serde::{Deserialize, Deserializer, Serialize};
use std::borrow::Cow;
#[derive(Serialize, Deserialize)]
struct Foo<'a> {
#[serde(deserialize_with = "func")]
#[serde(skip_serializing_if = "Option::is_none")]
#[serde(default)]
#[serde(borrow)]
foo: Option<Option<Cow<'a, str>>>,
}
#[allow(clippy::option_option)]
fn func<'a, D>(_: D) -> Result<Option<Option<Cow<'a, str>>>, D::Error>
where
D: Deserializer<'a>,
{
Ok(Some(Some(Cow::Borrowed("hi"))))
}
}
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