1 files changed, 26 insertions, 1 deletions
diff --git a/syncs/syncs_test.go b/syncs/syncs_test.go
index 9de72e22f..a6768e90b 100644
--- a/syncs/syncs_test.go
+++ b/syncs/syncs_test.go
@@ -4,7 +4,10 @@
 
 package syncs
 
-import "testing"
+import (
+	"context"
+	"testing"
+)
 
 func TestWaitGroupChan(t *testing.T) {
 	wg := NewWaitGroupChan()
@@ -48,3 +51,25 @@ func TestClosedChan(t *testing.T) {
 		}
 	}
 }
+
+func TestSemaphore(t *testing.T) {
+	s := NewSemaphore(2)
+	s.Acquire()
+	if !s.TryAcquire() {
+		t.Fatal("want true")
+	}
+	if s.TryAcquire() {
+		t.Fatal("want false")
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	if s.AcquireContext(ctx) {
+		t.Fatal("want false")
+	}
+	s.Release()
+	if !s.AcquireContext(context.Background()) {
+		t.Fatal("want true")
+	}
+	s.Release()
+	s.Release()
+}