rust-clippy/tests/ui/question_mark.fixed
bors d0b8f7508c Simplify if let statements
fixes: #8288

---

changelog: Allowing [`qustion_mark`] lint to check `if let` expressions that immediatly return unwrapped value
2022-07-08 16:12:00 +00:00

210 lines
3.4 KiB
Rust

// run-rustfix
#![allow(unreachable_code)]
#![allow(dead_code)]
#![allow(clippy::unnecessary_wraps)]
fn some_func(a: Option<u32>) -> Option<u32> {
a?;
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> {
(self.opt)?;
self.opt?;
let _ = Some(self.opt?);
let _ = self.opt?;
self.opt
}
}
#[derive(Clone)]
pub struct MoveStruct {
pub opt: Option<Vec<u32>>,
}
impl MoveStruct {
pub fn ref_func(&self) -> Option<Vec<u32>> {
self.opt.as_ref()?;
self.opt.clone()
}
pub fn mov_func_reuse(self) -> Option<Vec<u32>> {
self.opt.as_ref()?;
self.opt
}
pub fn mov_func_no_use(self) -> Option<Vec<u32>> {
self.opt.as_ref()?;
Some(Vec::new())
}
pub fn if_let_ref_func(self) -> Option<Vec<u32>> {
let v: &Vec<_> = self.opt.as_ref()?;
Some(v.clone())
}
pub fn if_let_mov_func(self) -> Option<Vec<u32>> {
let v = self.opt?;
Some(v)
}
}
fn func() -> Option<i32> {
fn f() -> Option<String> {
Some(String::new())
}
f()?;
Some(0)
}
fn func_returning_result() -> Result<i32, i32> {
Ok(1)
}
fn result_func(x: Result<i32, i32>) -> Result<i32, i32> {
let _ = x?;
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();
}
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> {
func_returning_result()?;
Ok(1)
}
fn err_immediate_return_and_do_something() -> Result<i32, i32> {
func_returning_result()?;
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
}
}
fn main() {}