rust/tests/ui/manual_map_option_2.fixed
Jason Newcomb 9500974bdb
Fix tracking of which locals would need to be captured in a closure.
* Captures by sub closures are now considered
* Copy types are correctly borrowed by reference when their value is used
* Fields are no longer automatically borrowed by value
* Bindings in `match` and `let` patterns are now checked to determine how a local is captured
2021-08-14 19:49:57 -04:00

51 lines
1.4 KiB
Rust

// run-rustfix
#![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 _ = Some(0).map(|x| {
let y = (String::new(), String::new());
(x, y.0)
});
// 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,
};
// Lint. `s` is captured by reference, so no lifetime issues.
let s = Some(String::new());
let _ = s.as_ref().map(|x| {
if let Some(ref s) = s { (x.clone(), s) } else { panic!() }
});
}