spyHandle.send(b, 2, 4);
        verify(mockOut).writeDirect(eq(b), eq(2), eq(4), eq(1));
    }

    @Test
    @DisplayName("unwrap returns this for compatible types and throws otherwise")
    void unwrap_success_and_failure() {
        SmbPipeHandleImpl handle = newHandleWithBasicStubs(0, "\\\\pipe\\\\z");

        // Happy path: unwrap to interface and concrete type