spyTarget.send(b, 1, 2);
        verify(out).writeDirect(b, 1, 2, 1);
    }

    @Test
    @DisplayName("sendrecv with null buffers throws relevant exceptions")
    void testSendRecvInvalidInputs() throws CIFSException {
        // Null out buffer for SMB2 path -> expect NPE when building request
        when(pipe.ensureTreeConnected()).thenReturn(tree);
        when(tree.acquire()).thenReturn(tree);