add support files and regression tests for #1124

Examples/test-suite/r_use_isnull.i

@@ -0,0 +1,34 @@
+%module r_use_isnull
+
+%inline %{
+// C++ code
+class circle {
+public:
+circle(double radius)
+{
+m_radius = radius;
+}
+double getArea() const
+{
+return (3.14 * m_radius * m_radius);
+}
+
+private:
+double m_radius;
+};
+
+class pointerTest {
+public:
+pointerTest() : m_circle(2) {}
+const circle * getCircle(int index) const {
+if (index == 0)
+return & m_circle;
+else
+return 0;
+}
+
+private:
+    circle m_circle;
+
+};
+ %}