use crossbeam_utils::thread; use rayon_core::ThreadPoolBuilder; #[derive(PartialEq, Eq, Debug)] struct Local(i32); scoped_tls::scoped_thread_local!(static LOCAL: Local); #[test] #[cfg_attr(any(target_os = "emscripten", target_family = "wasm"), ignore)] fn missing_scoped_tls() { LOCAL.set(&Local(42), || { let pool = ThreadPoolBuilder::new() .build() .expect("thread pool created"); // `LOCAL` is not set in the pool. pool.install(|| { assert!(!LOCAL.is_set()); }); }); } #[test] #[cfg_attr(any(target_os = "emscripten", target_family = "wasm"), ignore)] fn spawn_scoped_tls_threadpool() { LOCAL.set(&Local(42), || { LOCAL.with(|x| { thread::scope(|scope| { let pool = ThreadPoolBuilder::new() .spawn_handler(move |thread| { scope .builder() .spawn(move |_| { // Borrow the same local value in the thread pool. LOCAL.set(x, || thread.run()) }) .map(|_| ()) }) .build() .expect("thread pool created"); // The pool matches our local value. pool.install(|| { assert!(LOCAL.is_set()); LOCAL.with(|y| { assert_eq!(x, y); }); }); // If we change our local value, the pool is not affected. LOCAL.set(&Local(-1), || { pool.install(|| { assert!(LOCAL.is_set()); LOCAL.with(|y| { assert_eq!(x, y); }); }); }); }) .expect("scope threads ok"); // `thread::scope` will wait for the threads to exit before returning. }); }); } #[test] #[cfg_attr(any(target_os = "emscripten", target_family = "wasm"), ignore)] fn build_scoped_tls_threadpool() { LOCAL.set(&Local(42), || { LOCAL.with(|x| { ThreadPoolBuilder::new() .build_scoped( move |thread| LOCAL.set(x, || thread.run()), |pool| { // The pool matches our local value. pool.install(|| { assert!(LOCAL.is_set()); LOCAL.with(|y| { assert_eq!(x, y); }); }); // If we change our local value, the pool is not affected. LOCAL.set(&Local(-1), || { pool.install(|| { assert!(LOCAL.is_set()); LOCAL.with(|y| { assert_eq!(x, y); }); }); }); }, ) .expect("thread pool created"); // Internally, `std::thread::scope` will wait for the threads to exit before returning. }); }); }