feat: add test for return policy

Author: edmBernard

tests/cpp/test.cpp

@@ -149,6 +149,7 @@ class ClassForReturn {
   }
 
   cv::Mat& returnByRef() { return m_image; };
+  const cv::Mat& viewMatrix() { return m_image; };
 
   cv::Mat* returnByPointer() { return &m_image; };
 
@@ -200,9 +201,11 @@ PYBIND11_MODULE(test_module, m) {
   py::class_<ClassForReturn>(m, "ClassForReturn")
     .def(py::init<>())
     .def("changeInternal", &ClassForReturn::changeInternal)
-    .def("returnByRef", &ClassForReturn::returnByRef)
-    .def("returnByPointer", &ClassForReturn::returnByPointer)
     .def("returnByValue", &ClassForReturn::returnByValue)
+    .def("returnByRefButCopy", &ClassForReturn::returnByRef)
+    .def("returnByRef", &ClassForReturn::returnByRef, py::return_value_policy::reference_internal)
+    .def("viewMatrix", &ClassForReturn::returnByRef, py::return_value_policy::reference_internal)
+    .def("returnByPointer", &ClassForReturn::returnByPointer, py::return_value_policy::reference_internal)
     .def("returnInArgumentByRef", &ClassForReturn::returnInArgumentByRef)
     .def("returnInArgumentByPointer", &ClassForReturn::returnInArgumentByPointer)
     ;

tests/test_return.py

@@ -2,23 +2,43 @@
 from tests import test_module as tm
 
 
-# def test_return_by_ref():
-#   a = tm.ClassForReturn()
-#   assert(id(a.returnByRef()) == id(a.returnByRef()))
+def test_return_by_value():
+  a = tm.ClassForReturn()
+  assert(id(a.returnByValue()) != id(a.returnByValue()))
+  mat = a.returnByValue()
+  a.changeInternal()
+  assert(np.any(mat != a.returnByValue()))
 
-# def test_return_by_value():
-#   a = tm.ClassForReturn()
-#   assert(id(a.returnByValue()) != id(a.returnByValue()))
 
-# def test_return_by_pointer():
-#   a = tm.ClassForReturn()
-#   assert(id(a.returnByPointer()) == id(a.returnByPointer()))
+def test_return_by_ref_but_copy():
+  a = tm.ClassForReturn()
+  assert(id(a.returnByRef()) != id(a.returnByRef()))
+  mat = a.returnByRef()
+  a.changeInternal()
+  assert(np.any(mat != a.returnByValue()))
 
-# def test_return_by_argument_by_ref():
-#   pass
 
-# def test_return_by_argument_by_value():
-#   pass
+def test_return_by_ref():
+  a = tm.ClassForReturn()
+  assert(id(a.returnByRef()) != id(a.returnByRef()))
+  mat = a.viewMatrix()
+  a.changeInternal()
+  assert(np.all(mat == a.returnByValue()))
 
-# def test_return_by_argument_by_pointer():
-#   pass
+
+def test_return_by_pointer():
+  a = tm.ClassForReturn()
+  assert(id(a.returnByPointer()) != id(a.returnByPointer()))
+  mat = a.returnByPointer()
+  a.changeInternal()
+  assert(np.all(mat == a.returnByValue()))
+
+
+def test_return_by_argument_by_ref():
+  pass
+
+def test_return_by_argument_by_value():
+  pass
+
+def test_return_by_argument_by_pointer():
+  pass