38 lines
1.1 KiB
Rust
38 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 borrows returned from a try block must be valid for the lifetime of the
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// result variable
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let result: Result<(), &str> = try {
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let my_string = String::from("");
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let my_str: & str = & my_string;
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//~^ ERROR `my_string` does not live long enough
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Err(my_str) ?;
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Err("") ?;
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};
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do_something_with(result);
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}
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{
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// Test that borrows returned from try blocks freeze their referent
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let mut i = 5;
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let k = &mut i;
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let mut j: Result<(), &mut i32> = try {
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Err(k) ?;
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i = 10; //~ ERROR cannot assign to `i` because it is borrowed
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};
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::std::mem::drop(k); //~ ERROR use of moved value: `k`
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i = 40; //~ ERROR cannot assign to `i` because it is borrowed
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let i_ptr = if let Err(i_ptr) = j { i_ptr } else { panic ! ("") };
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*i_ptr = 50;
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}
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}
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