rust/tests/ui/overloaded/overloaded_deref_with_ref_pattern_issue15609.rs
2023-01-11 09:32:08 +00:00

38 lines
718 B
Rust

// run-pass
#![allow(dead_code)]
#![allow(unused_variables)]
// Test that we choose Deref or DerefMut appropriately based on mutability of ref bindings (#15609).
fn main() {
use std::cell::RefCell;
struct S {
node: E,
}
enum E {
Foo(u32),
Bar,
}
// Check match
let x = RefCell::new(S { node: E::Foo(0) });
let mut b = x.borrow_mut();
match b.node {
E::Foo(ref mut n) => *n += 1,
_ => (),
}
// Check let
let x = RefCell::new(0);
let mut y = x.borrow_mut();
let ref mut z = *y;
fn foo(a: &mut RefCell<Option<String>>) {
if let Some(ref mut s) = *a.borrow_mut() {
s.push('a')
}
}
}