Fix race condition in test

utils/pool/pool_test.go

@@ -1,6 +1,7 @@
 package pool
 
 import (
+	"sync"
 	"testing"
 
 	"github.com/navidrome/navidrome/log"
@@ -20,7 +21,10 @@ type testItem struct {
 	ID int
 }
 
-var processed []int
+var (
+	processed []int
+	mutex     sync.RWMutex
+)
 
 var _ = Describe("Pool", func() {
 	var pool *Pool
@@ -34,12 +38,19 @@ var _ = Describe("Pool", func() {
 		for i := 0; i < 5; i++ {
 			pool.Submit(&testItem{ID: i})
 		}
-		Eventually(func() []int { return processed }, "10s").Should(HaveLen(5))
+		Eventually(func() []int {
+			mutex.RLock()
+			defer mutex.RUnlock()
+			return processed
+		}, "10s").Should(HaveLen(5))
+
 		Expect(processed).To(ContainElements(0, 1, 2, 3, 4))
 	})
 })
 
 func execute(workload interface{}) {
+	mutex.Lock()
+	defer mutex.Unlock()
 	item := workload.(*testItem)
 	processed = append(processed, item.ID)
 }