45 lines
1.1 KiB
Rust
45 lines
1.1 KiB
Rust
// compile-flags: --edition 2018
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#![feature(try_blocks)]
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#[inline(never)]
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fn do_something_with<T>(_x: T) {}
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// This test checks that borrows made and returned inside try blocks are properly constrained
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pub fn main() {
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{
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// Test that a borrow which *might* be returned still freezes its referent
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let mut i = 222;
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let x: Result<&i32, ()> = try {
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Err(())?;
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&i
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};
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i = 0; //~ ERROR cannot assign to `i` because it is borrowed
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let _ = i;
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do_something_with(x);
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}
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{
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let x = String::new();
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let _y: Result<(), ()> = try {
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Err(())?;
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::std::mem::drop(x);
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};
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println!("{}", x); //~ ERROR borrow of moved value: `x`
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}
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{
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// Test that a borrow which *might* be assigned to an outer variable still freezes
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// its referent
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let mut i = 222;
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let mut j = &-1;
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let _x: Result<(), ()> = try {
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Err(())?;
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j = &i;
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};
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i = 0; //~ ERROR cannot assign to `i` because it is borrowed
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let _ = i;
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do_something_with(j);
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}
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}
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