Vendor things

third-party/vendor/loom/tests/yield.rs

@@ -0,0 +1,29 @@
+#![deny(warnings, rust_2018_idioms)]
+
+use loom::sync::atomic::AtomicUsize;
+use loom::thread;
+
+use std::sync::atomic::Ordering::Relaxed;
+use std::sync::Arc;
+
+#[test]
+fn yield_completes() {
+    loom::model(|| {
+        let inc = Arc::new(AtomicUsize::new(0));
+
+        {
+            let inc = inc.clone();
+            thread::spawn(move || {
+                inc.store(1, Relaxed);
+            });
+        }
+
+        loop {
+            if 1 == inc.load(Relaxed) {
+                return;
+            }
+
+            loom::thread::yield_now();
+        }
+    });
+}