I want to have conformal meshes in the interface of two solids but the import 2D algorithm misidentifies which nodes belongs to which sub-shape and raises an error.I went through source files and couldn't find the problem and I wast able to join Salome forum.

and here is the copied mesh :

it correctly identifies the node belonging to edge 541 but the next node is set to belong to another edge.this problem only happens when there is an extra vertex like so:

I suspect this part of the source code to be the problem:

// check if a not shared link lies on face boundary
        bool nodesOnBoundary = true;
        list< TopoDS_Shape > bndShapes;
        for ( int is1stN = 0; is1stN < 2 && nodesOnBoundary; ++is1stN )
        {
          const SMDS_MeshNode* n = is1stN ? link.node1() : link.node2();
          if ( !subShapeIDs.count( n->getshapeId() )) // n is assigned to FACE
          {
            for ( size_t iE = 0; iE < edges.size(); ++iE )
              if ( helper.CheckNodeU( edges[iE], n, u=0, projTol, /*force=*/true ))
              {
                BRep_Tool::Range(edges[iE],f,l);
                if ( Abs(u-f) < 2 * faceTol || Abs(u-l) < 2 * faceTol )
                  // duplicated node on vertex
                  return error("Source elements overlap one another");
                tgtFaceSM->RemoveNode( n );
                tgtMesh->SetNodeOnEdge( n, edges[iE], u );
                break;
}
nodesOnBoundary = subShapeIDs.count( n->getshapeId());
}