rust-clippy/tests/ui/question_mark.rs

361 lines
6.7 KiB
Rust

#![feature(try_blocks)]
#![allow(unreachable_code)]
#![allow(dead_code)]
#![allow(clippy::unnecessary_wraps)]
fn some_func(a: Option<u32>) -> Option<u32> {
if a.is_none() {
return None;
}
a
}
fn some_other_func(a: Option<u32>) -> Option<u32> {
if a.is_none() {
return None;
} else {
return Some(0);
}
unreachable!()
}
pub enum SeemsOption<T> {
Some(T),
None,
}
impl<T> SeemsOption<T> {
pub fn is_none(&self) -> bool {
match *self {
SeemsOption::None => true,
SeemsOption::Some(_) => false,
}
}
}
fn returns_something_similar_to_option(a: SeemsOption<u32>) -> SeemsOption<u32> {
if a.is_none() {
return SeemsOption::None;
}
a
}
pub struct CopyStruct {
pub opt: Option<u32>,
}
impl CopyStruct {
#[rustfmt::skip]
pub fn func(&self) -> Option<u32> {
if (self.opt).is_none() {
return None;
}
if self.opt.is_none() {
return None
}
let _ = if self.opt.is_none() {
return None;
} else {
self.opt
};
let _ = if let Some(x) = self.opt {
x
} else {
return None;
};
self.opt
}
}
#[derive(Clone)]
pub struct MoveStruct {
pub opt: Option<Vec<u32>>,
}
impl MoveStruct {
pub fn ref_func(&self) -> Option<Vec<u32>> {
if self.opt.is_none() {
return None;
}
self.opt.clone()
}
pub fn mov_func_reuse(self) -> Option<Vec<u32>> {
if self.opt.is_none() {
return None;
}
self.opt
}
pub fn mov_func_no_use(self) -> Option<Vec<u32>> {
if self.opt.is_none() {
return None;
}
Some(Vec::new())
}
pub fn if_let_ref_func(self) -> Option<Vec<u32>> {
let v: &Vec<_> = if let Some(ref v) = self.opt {
v
} else {
return None;
};
Some(v.clone())
}
pub fn if_let_mov_func(self) -> Option<Vec<u32>> {
let v = if let Some(v) = self.opt {
v
} else {
return None;
};
Some(v)
}
}
fn func() -> Option<i32> {
fn f() -> Option<String> {
Some(String::new())
}
if f().is_none() {
return None;
}
Some(0)
}
fn func_returning_result() -> Result<i32, i32> {
Ok(1)
}
fn result_func(x: Result<i32, i32>) -> Result<i32, i32> {
let _ = if let Ok(x) = x { x } else { return x };
if x.is_err() {
return x;
}
// No warning
let y = if let Ok(x) = x {
x
} else {
return Err(0);
};
// issue #7859
// no warning
let _ = if let Ok(x) = func_returning_result() {
x
} else {
return Err(0);
};
// no warning
if func_returning_result().is_err() {
return func_returning_result();
}
// no warning
let _ = if let Err(e) = x { Err(e) } else { Ok(0) };
// issue #11283
// no warning
#[warn(clippy::question_mark_used)]
{
if let Err(err) = Ok(()) {
return Err(err);
}
if Err::<i32, _>(0).is_err() {
return Err(0);
} else {
return Ok(0);
}
unreachable!()
}
Ok(y)
}
// see issue #8019
pub enum NotOption {
None,
First,
AfterFirst,
}
fn obj(_: i32) -> Result<(), NotOption> {
Err(NotOption::First)
}
fn f() -> NotOption {
if obj(2).is_err() {
return NotOption::None;
}
NotOption::First
}
fn do_something() {}
fn err_immediate_return() -> Result<i32, i32> {
if let Err(err) = func_returning_result() {
return Err(err);
}
Ok(1)
}
fn err_immediate_return_and_do_something() -> Result<i32, i32> {
if let Err(err) = func_returning_result() {
return Err(err);
}
do_something();
Ok(1)
}
// No warning
fn no_immediate_return() -> Result<i32, i32> {
if let Err(err) = func_returning_result() {
do_something();
return Err(err);
}
Ok(1)
}
// No warning
fn mixed_result_and_option() -> Option<i32> {
if let Err(err) = func_returning_result() {
return Some(err);
}
None
}
// No warning
fn else_if_check() -> Result<i32, i32> {
if true {
Ok(1)
} else if let Err(e) = func_returning_result() {
Err(e)
} else {
Err(-1)
}
}
// No warning
#[allow(clippy::manual_map)]
#[rustfmt::skip]
fn option_map() -> Option<bool> {
if let Some(a) = Some(false) {
Some(!a)
} else {
None
}
}
pub struct PatternedError {
flag: bool,
}
// No warning
fn pattern() -> Result<(), PatternedError> {
let res = Ok(());
if let Err(err @ PatternedError { flag: true }) = res {
return Err(err);
}
res
}
fn main() {}
// `?` is not the same as `return None;` if inside of a try block
fn issue8628(a: Option<u32>) -> Option<u32> {
let b: Option<u32> = try {
if a.is_none() {
return None;
}
32
};
b.or(Some(128))
}
fn issue6828_nested_body() -> Option<u32> {
try {
fn f2(a: Option<i32>) -> Option<i32> {
if a.is_none() {
return None;
// do lint here, the outer `try` is not relevant here
// https://github.com/rust-lang/rust-clippy/pull/11001#issuecomment-1610636867
}
Some(32)
}
123
}
}
// should not lint, `?` operator not available in const context
const fn issue9175(option: Option<()>) -> Option<()> {
if option.is_none() {
return None;
}
//stuff
Some(())
}
fn issue12337() -> Option<i32> {
let _: Option<i32> = try {
let Some(_) = Some(42) else {
return None;
};
123
};
Some(42)
}
fn issue11983(option: &Option<String>) -> Option<()> {
// Don't lint, `&Option` dose not impl `Try`.
let Some(v) = option else { return None };
let opt = Some(String::new());
// Don't lint, `branch` method in `Try` takes ownership of `opt`,
// and `(&opt)?` also doesn't work since it's `&Option`.
let Some(v) = &opt else { return None };
let mov = opt;
Some(())
}
struct Foo {
owned: Option<String>,
}
struct Bar {
foo: Foo,
}
#[allow(clippy::disallowed_names)]
fn issue12412(foo: &Foo, bar: &Bar) -> Option<()> {
// Don't lint, `owned` is behind a shared reference.
let Some(v) = &foo.owned else {
return None;
};
// Don't lint, `owned` is behind a shared reference.
let Some(v) = &bar.foo.owned else {
return None;
};
// lint
let Some(v) = bar.foo.owned.clone() else {
return None;
};
Some(())
}