[SOLVED] Error with test scene, Required plugins error

Hey,

I encounter an issue while testing my plugin. Here is the test :

class Communication_test : public Sofa_test<>
{
public:
    void checkPerformances(int numstep)
    {
        std::stringstream scene1 ;
        scene1 <<
                  "<?xml version='1.0' ?>                                                       \n"
                  "<Node name='root'>                                                           \n"
                  "   <RequiredPlugin name='Communication' />                                   \n"
                  "</Node>                                                                      \n";
        Node::SPtr root = SceneLoaderXML::loadFromMemory ("testscene", scene1.str().c_str(), scene1.str().size()) ;
        root->init(ExecParams::defaultInstance()) ;
        for(unsigned int i=0;i<numstep;i++)
            sofa::simulation::getSimulation()->animate(root.get(), 0.001);
    }
};

TEST_F(Communication_test, checkPerformancs) {
    ASSERT_NO_THROW(this->checkPerformances(2)) ;
}

But it fails with the following error message :

[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from Communication_test
[ RUN      ] Communication_test.checkPerformancs
[ERROR]   [DAGNode(root)] Object type "RequiredPlugin" creation Failed
/home/douaille/SOFA/sofaTestCommunication/applications/plugins/SofaTest/../SofaTest/Sofa_test.h:94: Failure
Failed
A message of type 'Error' was not expected but it was received. 
====================== Messages =======================
[DAGNode]: 
    Message type   : Error
    Message content: Object type "RequiredPlugin" creation Failed
    source code loc: /home/douaille/SOFA/sofaTestCommunication/SofaKernel/modules/SofaSimulationCommon/xml/NodeElement.cpp:83
      component: DAGNode(root)
===============================================================

/home/douaille/SOFA/sofaTestCommunication/applications/plugins/SofaTest/../SofaTest/Sofa_test.h:94: Failure
Failed
A message of type 'Error' was not expected but it was received. 
====================== Messages =======================
[SceneLoaderXML]: 
    Message type   : Error
    Message content: Node initialization failed. 

    source code loc: testscene:2
      component: SceneLoaderXML
===============================================================

[WARNING] [DAGSimulation(Simulation)] ERROR in Simulation::animate(): AnimationLoop expected at the root node
[WARNING] [DAGSimulation(Simulation)] ERROR in Simulation::animate(): AnimationLoop expected at the root node
[  FAILED  ] Communication_test.checkPerformancs (3 ms)
[----------] 1 test from Communication_test (3 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (3 ms total)
[  PASSED  ] 0 tests.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] Communication_test.checkPerformancs

 1 FAILED TEST
[ERROR]   [SceneLoaderXML] Node initialization failed. 

I don’t understand what is the problem. When running sofa the plugin “Communication” works well. For unknown reason, RequiredPlugin is not created.

Do you have any tips ? Is it a bug ?

Edit : the exactly same scene works well with runSofa.