QEnum: Adapt to the new enum implementation

QEnum was implemented with Python enums, as opposed to the
old C++ enums. Now that support for Python enums is built
into PySide, it is necessary to keep the implementing
Python modules always the same.

This patch prepares QEnum and PyEnum compatibility for the
upcoming embedding of old enum implementations.

As a side effect: Python 3.6 and 3.7 had a hard-to-find
refcount error when creating new enums.

Task-number: PYSIDE-1735
Change-Id: Ic44459c8e319d6d0308c7366beafa6fe7df41b79
Pick-to: 6.3
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 4 insertions, 28 deletions

diff --git a/sources/pyside6/libpyside/pysideqenum.cpp b/sources/pyside6/libpyside/pysideqenum.cpp
index 3713e3c57..4ccbcbaff 100644
--- a/sources/pyside6/libpyside/pysideqenum.cpp
+++ b/sources/pyside6/libpyside/pysideqenum.cpp
@@ -111,38 +111,14 @@ int isFlag(PyObject *obType)
      * The function is called in MetaObjectBuilderPrivate::parsePythonType
      * again to obtain the flag value.
      */
-    if (!PyType_Check(obType)) {
-        PyErr_Format(PyExc_TypeError, "a class argument was expected, not a '%.200s' instance",
-                                      Py_TYPE(obType)->tp_name);
-        return -1;
-    };
-    auto *type = reinterpret_cast<PyTypeObject *>(obType);
-    PyObject *mro = type->tp_mro;
-    Py_ssize_t i, n = PyTuple_GET_SIZE(mro);
-    bool right_module = false;
-    bool have_enum = false;
-    bool have_flag = false;
-    bool have_members = PyObject_HasAttr(obType, PyMagicName::members());
-    for (i = 0; i < n; i++) {
-        obType = PyTuple_GET_ITEM(mro, i);
-        type = reinterpret_cast<PyTypeObject *>(obType);
-        AutoDecRef mod(PyObject_GetAttr(obType, PyMagicName::module()));
-        QByteArray cmod = String::toCString(mod);
-        QByteArray cname = type->tp_name;
-        if (cmod == "enum") {
-            right_module = true;
-            if (cname == "Enum")
-                have_enum = true;
-            else if (cname == "Flag")
-                have_flag = true;
-        }
-    }
-    if (!right_module || !(have_enum || have_flag) || !have_members) {
+    int res = enumIsFlag(obType);
+    if (res < 0) {
+        auto *type = reinterpret_cast<PyTypeObject *>(obType);
         PyErr_Format(PyExc_TypeError, "type %.200s does not inherit from 'Enum' or 'Flag'",
                                       type->tp_name);
         return -1;
     }
-    return bool(have_flag);
+    return bool(res);
 }
 
 PyObject *QEnumMacro(PyObject *pyenum, bool flag)