1 files changed, 99 insertions, 0 deletions
diff --git a/compiler/rustc_thread_pool/tests/scoped_threadpool.rs b/compiler/rustc_thread_pool/tests/scoped_threadpool.rs
new file mode 100644
index 00000000000..295da650e88
--- /dev/null
+++ b/compiler/rustc_thread_pool/tests/scoped_threadpool.rs
@@ -0,0 +1,99 @@
+#![allow(unused_crate_dependencies)]
+
+use crossbeam_utils::thread;
+use rustc_thread_pool::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.
+        });
+    });
+}