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// run-rustfix
#![warn(clippy::needless_question_mark)]
#![allow(
clippy::needless_return,
clippy::unnecessary_unwrap,
clippy::upper_case_acronyms,
dead_code,
unused_must_use
)]
#![feature(custom_inner_attributes)]
struct TO {
magic: Option<usize>,
}
struct TR {
magic: Result<usize, bool>,
}
fn simple_option_bad1(to: TO) -> Option<usize> {
// return as a statement
return to.magic;
}
// formatting will add a semi-colon, which would make
// this identical to the test case above
#[rustfmt::skip]
fn simple_option_bad2(to: TO) -> Option<usize> {
// return as an expression
return to.magic
}
fn simple_option_bad3(to: TO) -> Option<usize> {
// block value "return"
to.magic
}
fn simple_option_bad4(to: Option<TO>) -> Option<usize> {
// single line closure
to.and_then(|t| t.magic)
}
// formatting this will remove the block brackets, making
// this test identical to the one above
#[rustfmt::skip]
fn simple_option_bad5(to: Option<TO>) -> Option<usize> {
// closure with body
to.and_then(|t| {
t.magic
})
}
fn simple_result_bad1(tr: TR) -> Result<usize, bool> {
return tr.magic;
}
// formatting will add a semi-colon, which would make
// this identical to the test case above
#[rustfmt::skip]
fn simple_result_bad2(tr: TR) -> Result<usize, bool> {
return tr.magic
}
fn simple_result_bad3(tr: TR) -> Result<usize, bool> {
tr.magic
}
fn simple_result_bad4(tr: Result<TR, bool>) -> Result<usize, bool> {
tr.and_then(|t| t.magic)
}
// formatting this will remove the block brackets, making
// this test identical to the one above
#[rustfmt::skip]
fn simple_result_bad5(tr: Result<TR, bool>) -> Result<usize, bool> {
tr.and_then(|t| {
t.magic
})
}
fn also_bad(tr: Result<TR, bool>) -> Result<usize, bool> {
if tr.is_ok() {
let t = tr.unwrap();
return t.magic;
}
Err(false)
}
fn false_positive_test<U, T>(x: Result<(), U>) -> Result<(), T>
where
T: From<U>,
{
Ok(x?)
}
// not quite needless
fn deref_ref(s: Option<&String>) -> Option<&str> {
Some(s?)
}
fn main() {}
// #6921 if a macro wraps an expr in Some( ) and the ? is in the macro use,
// the suggestion fails to apply; do not lint
macro_rules! some_in_macro {
($expr:expr) => {
|| -> _ { Some($expr) }()
};
}
pub fn test1() {
let x = Some(3);
let _x = some_in_macro!(x?);
}
// this one is ok because both the ? and the Some are both inside the macro def
macro_rules! some_and_qmark_in_macro {
($expr:expr) => {
|| -> Option<_> { Some($expr) }()
};
}
pub fn test2() {
let x = Some(3);
let _x = some_and_qmark_in_macro!(x?);
}
async fn async_option_bad(to: TO) -> Option<usize> {
let _ = Some(3);
to.magic
}
async fn async_deref_ref(s: Option<&String>) -> Option<&str> {
Some(s?)
}
async fn async_result_bad(s: TR) -> Result<usize, bool> {
s.magic
}
|
