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|
#![warn(clippy::manual_map)]
#![allow(clippy::toplevel_ref_arg)]
fn main() {
// Lint. `y` is declared within the arm, so it isn't captured by the map closure
let _ = match Some(0) {
//~^ manual_map
Some(x) => Some({
let y = (String::new(), String::new());
(x, y.0)
}),
None => None,
};
// Don't lint. `s` is borrowed until partway through the arm, but needs to be captured by the map
// closure
let s = Some(String::new());
let _ = match &s {
Some(x) => Some((x.clone(), s)),
None => None,
};
// Don't lint. `s` is borrowed until partway through the arm, but needs to be captured by the map
// closure
let s = Some(String::new());
let _ = match &s {
Some(x) => Some({
let clone = x.clone();
let s = || s;
(clone, s())
}),
None => None,
};
// Don't lint. `s` is borrowed until partway through the arm, but needs to be captured as a mutable
// reference by the map closure
let mut s = Some(String::new());
let _ = match &s {
Some(x) => Some({
let clone = x.clone();
let ref mut s = s;
(clone, s)
}),
None => None,
};
let s = Some(String::new());
// Lint. `s` is captured by reference, so no lifetime issues.
let _ = match &s {
//~^ manual_map
Some(x) => Some({ if let Some(ref s) = s { (x.clone(), s) } else { panic!() } }),
None => None,
};
// Don't lint this, type of `s` is coercioned from `&String` to `&str`
let x: Option<(String, &str)> = match &s {
Some(x) => Some({ if let Some(ref s) = s { (x.clone(), s) } else { panic!() } }),
None => None,
};
// Issue #7820
unsafe fn f(x: u32) -> u32 {
x
}
unsafe {
let _ = match Some(0) {
//~^ manual_map
Some(x) => Some(f(x)),
None => None,
};
}
let _ = match Some(0) {
//~^ manual_map
Some(x) => unsafe { Some(f(x)) },
None => None,
};
let _ = match Some(0) {
//~^ manual_map
Some(x) => Some(unsafe { f(x) }),
None => None,
};
}
// issue #12659
mod with_type_coercion {
trait DummyTrait {}
fn foo<T: DummyTrait, F: Fn() -> Result<T, ()>>(f: F) {
// Don't lint
let _: Option<Result<Box<dyn DummyTrait>, ()>> = match Some(0) {
Some(_) => Some(match f() {
Ok(res) => Ok(Box::new(res)),
_ => Err(()),
}),
None => None,
};
let _: Option<Box<&[u8]>> = match Some(()) {
Some(_) => Some(Box::new(b"1234")),
None => None,
};
let x = String::new();
let _: Option<Box<&str>> = match Some(()) {
Some(_) => Some(Box::new(&x)),
None => None,
};
let _: Option<&str> = match Some(()) {
Some(_) => Some(&x),
None => None,
};
let _ = match Some(0) {
//~^ manual_map
Some(_) => Some(match f() {
Ok(res) => Ok(Box::new(res)),
_ => Err(()),
}),
None => None,
};
}
#[allow(clippy::redundant_allocation)]
fn bar() {
fn f(_: Option<Box<&[u8]>>) {}
fn g(b: &[u8]) -> Box<&[u8]> {
Box::new(b)
}
let x: &[u8; 4] = b"1234";
f(match Some(()) {
Some(_) => Some(Box::new(x)),
None => None,
});
let _: Option<Box<&[u8]>> = match Some(0) {
//~^ manual_map
Some(_) => Some(g(x)),
None => None,
};
}
fn with_fn_ret(s: &Option<String>) -> Option<(String, &str)> {
// Don't lint, `map` doesn't work as the return type is adjusted.
match s {
Some(x) => Some({ if let Some(s) = s { (x.clone(), s) } else { panic!() } }),
None => None,
}
}
fn with_fn_ret_2(s: &Option<String>) -> Option<(String, &str)> {
if true {
// Don't lint, `map` doesn't work as the return type is adjusted.
return match s {
Some(x) => Some({ if let Some(s) = s { (x.clone(), s) } else { panic!() } }),
None => None,
};
}
None
}
#[allow(clippy::needless_late_init)]
fn with_fn_ret_3<'a>(s: &'a Option<String>) -> Option<(String, &'a str)> {
let x: Option<(String, &'a str)>;
x = {
match s {
Some(x) => Some({ if let Some(s) = s { (x.clone(), s) } else { panic!() } }),
None => None,
}
};
x
}
}
|
