From bee9120458dd3eb2c1486dd6c2344ec2c582f1b8 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sun, 7 Jul 2024 09:19:32 +0200
Subject: [PATCH] once_lock: make test not take as long in Miri

---
 library/std/src/sync/once_lock.rs | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/library/std/src/sync/once_lock.rs b/library/std/src/sync/once_lock.rs
index f52b9e52c54..fe243550606 100644
--- a/library/std/src/sync/once_lock.rs
+++ b/library/std/src/sync/once_lock.rs
@@ -80,14 +80,21 @@
 /// static LIST: OnceList<u32> = OnceList::new();
 /// static COUNTER: AtomicU32 = AtomicU32::new(0);
 ///
-/// let vec = (0..thread::available_parallelism().unwrap().get()).map(|_| thread::spawn(|| {
-///     while let i @ 0..=1000 = COUNTER.fetch_add(1, Ordering::Relaxed) {
-///         LIST.push(i);
+/// # const LEN: u32 = if cfg!(miri) { 50 } else { 1000 };
+/// # /*
+/// const LEN: u32 = 1000;
+/// # */
+/// thread::scope(|s| {
+///     for _ in 0..thread::available_parallelism().unwrap().get() {
+///         s.spawn(|| {
+///             while let i @ 0..LEN = COUNTER.fetch_add(1, Ordering::Relaxed) {
+///                 LIST.push(i);
+///             }
+///         });
 ///     }
-/// })).collect::<Vec<thread::JoinHandle<_>>>();
-/// vec.into_iter().for_each(|handle| handle.join().unwrap());
+/// });
 ///
-/// for i in 0..=1000 {
+/// for i in 0..LEN {
 ///     assert!(LIST.contains(&i));
 /// }
 ///