ENH: Add support for Python 3.12+

Initialization APIs and update deprecated usage

Author: hjmjohnson

generated_cpp_515/com_trolltech_qt_core/com_trolltech_qt_core4.h

@@ -417,7 +417,7 @@ enum class QCborSimpleType{
 enum class QCborTag{
 };
 enum QtMsgType{
-  QtDebugMsg = ::QtDebugMsg,   QtWarningMsg = ::QtWarningMsg,   QtCriticalMsg = ::QtCriticalMsg,   QtFatalMsg = ::QtFatalMsg,   QtInfoMsg = ::QtInfoMsg,   QtSystemMsg = ::QtSystemMsg};
+  QtDebugMsg = ::QtDebugMsg,   QtWarningMsg = ::QtWarningMsg,   QtCriticalMsg = ::QtCriticalMsg,   QtFatalMsg = ::QtFatalMsg,   QtInfoMsg = ::QtInfoMsg,   QtCriticalMsg = ::QtCriticalMsg};
 public slots:
 };
 

src/PythonQt.cpp

@@ -287,15 +287,17 @@ void PythonQt::init(int flags, const QByteArray& pythonQtModuleName)
       QtDebugMsg,
       QtWarningMsg,
       QtCriticalMsg,
+      QtCriticalMsg,
       QtFatalMsg,
-      QtSystemMsg
+      QtCriticalMsg
     };
     const char* enumNames[] = {
       "QtDebugMsg",
       "QtWarningMsg",
-      "QtCriticalMsg",
+      "QtCriticalMsg", // Qt6 replacement of QtSystemMsg
+      "QtSystemMsg", // Qt5 deprecated name QtSystemMsg
       "QtFatalMsg",
-      "QtSystemMsg"
+      "QtCriticalMsg"
     };
 
     for (auto i = 0u; i < sizeof(enumValues)/sizeof(int); i++) {
@@ -341,11 +343,71 @@ PythonQt::PythonQt(int flags, const QByteArray& pythonQtModuleName)
   _p->_initFlags = flags;
 
   if ((flags & PythonAlreadyInitialized) == 0) {
-    Py_SetProgramName(const_cast<wchar_t*>(L"PythonQt"));
+#if PY_VERSION_HEX < 0x030C0000
+    // Python < 3.12: legacy initialization
+    Py_SetProgramName((wchar_t*)L"PythonQt");
+    Py_Initialize();
+
+#elif PY_VERSION_HEX < 0x030D0000
+    // Python 3.12: Py_SetProgramName is deprecated, use PyConfig
+    PyConfig config;
+    PyStatus status;
+
+    PyConfig_InitPythonConfig(&config);
+    status = PyConfig_SetString(&config, &config.program_name, L"PythonQt");
+    if (PyStatus_Exception(status)) {
+      PyConfig_Clear(&config);
+      Py_ExitStatusException(status);
+    }
+
+    status = Py_InitializeFromConfig(&config);
+    PyConfig_Clear(&config);
+    if (PyStatus_Exception(status)) {
+      Py_ExitStatusException(status);
+    }
+
+#else
+    // Python >= 3.13: Py_SetProgramName is removed
+    PyConfig config;
+    PyStatus status;
+
+    PyConfig_InitPythonConfig(&config);
+    status = PyConfig_SetString(&config, &config.program_name, L"PythonQt");
+    if (PyStatus_Exception(status)) {
+      PyConfig_Clear(&config);
+      Py_ExitStatusException(status);
+    }
+
+    status = Py_InitializeFromConfig(&config);
+    PyConfig_Clear(&config);
+    if (PyStatus_Exception(status)) {
+      Py_ExitStatusException(status);
+    }
+#endif
+
 
     if (flags & IgnoreSiteModule) {
       // this prevents the automatic importing of Python site files
+#if PY_VERSION_HEX < 0x030B0000
+      // Python < 3.11  // Use legacy global flags
       Py_NoSiteFlag = 1;
+      Py_Initialize();
+#elif PY_VERSION_HEX < 0x030D0000
+      // Python == 3.12
+      // Py_NoSiteFlag is deprecated (still available, but use PyConfig preferred)
+      PyConfig config;
+      PyStatus status;
+
+      PyConfig_InitPythonConfig(&config);
+      config.site_import = 0;
+
+      status = Py_InitializeFromConfig(&config);
+      PyConfig_Clear(&config);
+
+      if (PyStatus_Exception(status)) {
+        Py_ExitStatusException(status);
+      }
+#endif
     }
     Py_Initialize();
   }
@@ -1155,7 +1217,13 @@ void PythonQt::removeVariable(PyObject* object, const QString& name)
   if (PyDict_Check(object)) {
     PyDict_DelItemString(object, QStringToPythonCharPointer(name));
   } else {
+#if PY_VERSION_HEX < 0x030C0000
     PyObject_DelAttrString(object, QStringToPythonCharPointer(name));
+#else
+    PyObject *pname = PyUnicode_FromString(QStringToPythonCharPointer(name));
+    PyObject_DelAttr(object, pname);
+    Py_DECREF(pname);
+#endif
   }
 }