[Test] Add unit test for Ref

unittest/CMakeLists.txt

 # 
-# Copyright (c) 2016 CNRS
+# Copyright (c) 2016-2018 CNRS
 # 
 # This file is part of eigenpy
 # eigenpy is free software: you can redistribute it
@@ -40,4 +40,5 @@ ADD_CUSTOM_TARGET(check COMMAND ${CMAKE_CTEST_COMMAND})
 
 ADD_LIB_UNIT_TEST(matrix "eigen3")
 ADD_LIB_UNIT_TEST(geometry "eigen3")
+ADD_LIB_UNIT_TEST(ref "eigen3")
 

unittest/ref.cpp

+/*
+ * Copyright 2018, Justin Carpentier <jcarpent@laas.fr>, LAAS-CNRS
+ *
+ * This file is part of eigenpy.
+ * eigenpy is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ * eigenpy is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.  You should
+ * have received a copy of the GNU Lesser General Public License along
+ * with eigenpy.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "eigenpy/eigenpy.hpp"
+#include <iostream>
+
+using namespace Eigen;
+using namespace eigenpy;
+
+template<typename MatType>
+void printMatrix(const eigenpy::Ref<MatType> & mat)
+{
+  if(MatType::IsVectorAtCompileTime)
+    std::cout << "isVector" << std::endl;
+  std::cout << "size: cols " << mat.cols() << " rows " << mat.rows() << std::endl;
+  std::cout << mat << std::endl;
+}
+
+template<typename MatType>
+void printVector(const eigenpy::Ref<MatType> & mat)
+{
+  EIGEN_STATIC_ASSERT_VECTOR_ONLY(MatType);
+  printMatrix(mat);
+}
+
+template<typename MatType>
+void setOnes(eigenpy::Ref<MatType> mat)
+{
+  mat.setOnes();
+}
+
+BOOST_PYTHON_MODULE(ref)
+{
+  namespace bp = boost::python;
+  eigenpy::enableEigenPy();
+  
+  bp::def("printMatrix", printMatrix<Vector3d>);
+  bp::def("printMatrix", printMatrix<VectorXd>);
+  bp::def("printMatrix", printMatrix<MatrixXd>);
+  
+  bp::def("printVector", printVector<VectorXd>);
+
+  bp::def("setOnes", setOnes<Vector3d>);
+  bp::def("setOnes", setOnes<VectorXd>);
+  bp::def("setOnes", setOnes<MatrixXd>);
+}