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

98 lines
1.8 KiB
Rust

// Test that we still see borrowck errors of various kinds when using
// indexing and autoderef in combination.
use std::ops::{Index, IndexMut};
struct Foo {
x: isize,
y: isize,
}
impl<'a> Index<&'a String> for Foo {
type Output = isize;
fn index(&self, z: &String) -> &isize {
if *z == "x" {
&self.x
} else {
&self.y
}
}
}
impl<'a> IndexMut<&'a String> for Foo {
fn index_mut(&mut self, z: &String) -> &mut isize {
if *z == "x" {
&mut self.x
} else {
&mut self.y
}
}
}
fn test1(mut f: Box<Foo>, s: String) {
let p = &mut f[&s];
let q = &f[&s]; //~ ERROR cannot borrow
p.use_mut();
}
fn test2(mut f: Box<Foo>, s: String) {
let p = &mut f[&s];
let q = &mut f[&s]; //~ ERROR cannot borrow
p.use_mut();
}
struct Bar {
foo: Foo
}
fn test3(mut f: Box<Bar>, s: String) {
let p = &mut f.foo[&s];
let q = &mut f.foo[&s]; //~ ERROR cannot borrow
p.use_mut();
}
fn test4(mut f: Box<Bar>, s: String) {
let p = &f.foo[&s];
let q = &f.foo[&s];
p.use_ref();
}
fn test5(mut f: Box<Bar>, s: String) {
let p = &f.foo[&s];
let q = &mut f.foo[&s]; //~ ERROR cannot borrow
p.use_ref();
}
fn test6(mut f: Box<Bar>, g: Foo, s: String) {
let p = &f.foo[&s];
f.foo = g; //~ ERROR cannot assign
p.use_ref();
}
fn test7(mut f: Box<Bar>, g: Bar, s: String) {
let p = &f.foo[&s];
*f = g; //~ ERROR cannot assign
p.use_ref();
}
fn test8(mut f: Box<Bar>, g: Foo, s: String) {
let p = &mut f.foo[&s];
f.foo = g; //~ ERROR cannot assign
p.use_mut();
}
fn test9(mut f: Box<Bar>, g: Bar, s: String) {
let p = &mut f.foo[&s];
*f = g; //~ ERROR cannot assign
p.use_mut();
}
fn main() {
}
trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { } }
impl<T> Fake for T { }