Experiment: specify indirect bases

Author: rwgk

tests/test_python_multiple_inheritance.cpp

@@ -26,6 +26,14 @@ struct CppDrvd : CppBase {
     int drvd_value;
 };
 
+struct CppDrv2 : CppDrvd {
+    explicit CppDrv2(int value) : CppDrvd(value), drv2_value(value * 5) {}
+    int get_drv2_value() const { return drv2_value; }
+
+private:
+    int drv2_value;
+};
+
 } // namespace test_python_multiple_inheritance
 
 TEST_SUBMODULE(python_multiple_inheritance, m) {
@@ -42,4 +50,12 @@ TEST_SUBMODULE(python_multiple_inheritance, m) {
         .def("reset_drvd_value", &CppDrvd::reset_drvd_value)
         .def("get_base_value_from_drvd", &CppDrvd::get_base_value_from_drvd)
         .def("reset_base_value_from_drvd", &CppDrvd::reset_base_value_from_drvd);
+
+#if 1 // This works.
+    py::class_<CppDrv2, CppDrvd>(m, "CppDrv2")
+#else // Apparent undefined behavior.
+    py::class_<CppDrv2, CppDrvd, CppBase>(m, "CppDrv2")
+#endif
+        .def(py::init<int>())
+        .def("get_drv2_value", &CppDrv2::get_drv2_value);
 }

tests/test_python_multiple_inheritance.py

@@ -12,6 +12,10 @@ class PPCC(PC, m.CppDrvd):
     pass
 
 
+class PPCC2(PC, m.CppDrv2):
+    pass
+
+
 def test_PC():
     d = PC(11)
     assert d.get_base_value() == 11
@@ -33,3 +37,10 @@ def test_PPCC():
     d.reset_base_value_from_drvd(30)
     assert d.get_base_value() == 30
     assert d.get_base_value_from_drvd() == 30
+
+
+def test_PPCC2():
+    d = PPCC2(13)
+    assert d.get_drv2_value() == 65
+    assert d.get_drvd_value() == 39
+    assert d.get_base_value() == 13