f, err := os.CreateTemp(t.TempDir(), "lock")
	if err != nil {
		t.Fatal(err)
	}
	f.Close()
	defer func() {
		err = os.Remove(f.Name())
		if err != nil {
			t.Fatal(err)
		}
	}()

	rlk, err := RLockedOpenFile(f.Name())
	if err != nil {
		t.Fatal(err)
	}
	isClosed := rlk.IsClosed()
	if isClosed {
		t.Fatal("File ref count shouldn't be zero")
	}

	// Increase reference count to 2.
	rlk.IncLockRef()