// run-rustfix #![deny(rust_2021_incompatible_closure_captures)] //~^ NOTE: the lint level is defined here use std::thread; #[derive(Debug)] struct Foo(i32); impl Drop for Foo { fn drop(&mut self) { println!("{:?} dropped", self.0); } } /* Test Send Trait Migration */ struct SendPointer(*mut i32); unsafe impl Send for SendPointer {} fn test_send_trait() { let mut f = 10; let fptr = SendPointer(&mut f as *mut i32); thread::spawn(move || unsafe { //~^ ERROR: changes to closure capture //~| NOTE: in Rust 2018, this closure implements `Send` //~| NOTE: for more information, see //~| HELP: add a dummy let to cause `fptr` to be fully captured *fptr.0 = 20; //~^ NOTE: in Rust 2018, this closure captures all of `fptr`, but in Rust 2021, it will only capture `fptr.0` }); } /* Test Sync Trait Migration */ struct CustomInt(*mut i32); struct SyncPointer(CustomInt); unsafe impl Sync for SyncPointer {} unsafe impl Send for CustomInt {} fn test_sync_trait() { let mut f = 10; let f = CustomInt(&mut f as *mut i32); let fptr = SyncPointer(f); thread::spawn(move || unsafe { //~^ ERROR: changes to closure capture //~| NOTE: in Rust 2018, this closure implements `Sync` //~| NOTE: in Rust 2018, this closure implements `Send` //~| NOTE: for more information, see //~| HELP: add a dummy let to cause `fptr` to be fully captured *fptr.0.0 = 20; //~^ NOTE: in Rust 2018, this closure captures all of `fptr`, but in Rust 2021, it will only capture `fptr.0.0` }); } /* Test Clone Trait Migration */ struct S(Foo); struct T(i32); struct U(S, T); impl Clone for U { fn clone(&self) -> Self { U(S(Foo(0)), T(0)) } } fn test_clone_trait() { let f = U(S(Foo(0)), T(0)); let c = || { //~^ ERROR: changes to closure capture in Rust 2021 will affect drop order and which traits the closure implements //~| NOTE: in Rust 2018, this closure implements `Clone` //~| NOTE: for more information, see //~| HELP: add a dummy let to cause `f` to be fully captured let f_1 = f.1; //~^ NOTE: in Rust 2018, this closure captures all of `f`, but in Rust 2021, it will only capture `f.1` println!("{:?}", f_1.0); }; let c_clone = c.clone(); c_clone(); } //~^ NOTE: in Rust 2018, `f` is dropped here, but in Rust 2021, only `f.1` will be dropped here as part of the closure fn main() { test_send_trait(); test_sync_trait(); test_clone_trait(); }