}

    /**
     * Test for close() idempotency.
     * Verifies that calling close multiple times has the same effect as calling it once.
     */
    @Test
    void testClose_idempotency() {
        // Mock a tree that tracks close state
        SmbTree idempotentTree = mock(SmbTree.class);
        doNothing().when(idempotentTree).close();

        // Close multiple times