REF: Update verbose/optimize flag handling for Python 3.11 compatibility

Add conditional checks for the `verbose` flag to distinguish
between legacy `Py_VerboseFlag` `Py_OptimizeFlag` and modern `sys.verbose` usage,
ensuring compatibility with Python versions 3.11 and later.

• Python is moving away from global interpreter state.
• Use of global variables like Py_VerboseFlag is not thread-safe.
• Python 3.12+ removes or restricts access to such globals in favor of
  per-interpreter APIs.

Author: hjmjohnson

src/PythonQtImporter.cpp

@@ -309,7 +309,12 @@ PythonQtImporter_load_module(PyObject *obj, PyObject *args)
     }
 
     Py_DECREF(code);
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
     if (Py_VerboseFlag) {
+#else
+    PyObject* verbose_flag = PySys_GetObject("verbose");
+    if (verbose_flag && PyLong_AsLong(verbose_flag) > 0) {
+#endif
       PySys_WriteStderr("import %s # loaded from %s\n",
         fullname, QStringToPythonConstCharPointer(fullPath));
     }
@@ -556,9 +561,15 @@ void PythonQtImport::writeCompiledModule(PyCodeObject *co, const QString& filena
   }
   fp = open_exclusive(filename);
   if (fp == nullptr) {
-    if (Py_VerboseFlag)
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+    if (Py_VerboseFlag) {
+#else
+    PyObject* verbose_flag = PySys_GetObject("verbose");
+    if (verbose_flag && PyLong_AsLong(verbose_flag) > 0) {
+#endif
       PySys_WriteStderr(
       "# can't create %s\n", QStringToPythonConstCharPointer(filename));
+    }
     return;
   }
   PyMarshal_WriteLongToFile(PyImport_GetMagicNumber(), fp, Py_MARSHAL_VERSION);
@@ -567,8 +578,14 @@ void PythonQtImport::writeCompiledModule(PyCodeObject *co, const QString& filena
   PyMarshal_WriteLongToFile(sourceSize, fp, Py_MARSHAL_VERSION);
   PyMarshal_WriteObjectToFile((PyObject *)co, fp, Py_MARSHAL_VERSION);
   if (ferror(fp)) {
-    if (Py_VerboseFlag)
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+    if (Py_VerboseFlag) {
+#else
+    PyObject* verbose_flag = PySys_GetObject("verbose");
+    if (verbose_flag && PyLong_AsLong(verbose_flag) > 0) {
+#endif
       PySys_WriteStderr("# can't write %s\n", QStringToPythonConstCharPointer(filename));
+    }
     /* Don't keep partial file */
     fclose(fp);
     QFile::remove(filename);
@@ -579,7 +596,12 @@ void PythonQtImport::writeCompiledModule(PyCodeObject *co, const QString& filena
   PyMarshal_WriteLongToFile(mtime, fp, Py_MARSHAL_VERSION);
   fflush(fp);
   fclose(fp);
-  if (Py_VerboseFlag) {
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+    if (Py_VerboseFlag) {
+#else
+    PyObject* verbose_flag = PySys_GetObject("verbose");
+    if (verbose_flag && PyLong_AsLong(verbose_flag) > 0) {
+#endif
     PySys_WriteStderr("# wrote %s\n", QStringToPythonConstCharPointer(filename));
   }
 }
@@ -605,9 +627,15 @@ PythonQtImport::unmarshalCode(const QString& path, const QByteArray& data, time_
   }
 
   if (getLong((unsigned char *)buf) != PyImport_GetMagicNumber()) {
-    if (Py_VerboseFlag)
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+    if (Py_VerboseFlag) {
+#else
+    PyObject* verbose_flag = PySys_GetObject("verbose");
+    if (verbose_flag && PyLong_AsLong(verbose_flag) > 0) {
+#endif
       PySys_WriteStderr("# %s has bad magic\n",
-            QStringToPythonConstCharPointer(path));
+                        QStringToPythonConstCharPointer(path));
+    }
     Py_INCREF(Py_None);
     return Py_None;
   }
@@ -616,9 +644,15 @@ PythonQtImport::unmarshalCode(const QString& path, const QByteArray& data, time_
     time_t timeDiff = getLong((unsigned char *)buf + 4) - mtime;
     if (timeDiff<0) { timeDiff = -timeDiff; }
     if (timeDiff > 1) {
-      if (Py_VerboseFlag)
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+      if (Py_VerboseFlag) {
+#else
+      PyObject* verbose_flag = PySys_GetObject("verbose");
+      if (verbose_flag && PyLong_AsLong(verbose_flag) > 0) {
+#endif
         PySys_WriteStderr("# %s has bad mtime\n",
-        QStringToPythonConstCharPointer(path));
+                          QStringToPythonConstCharPointer(path));
+      }
       Py_INCREF(Py_None);
       return Py_None;
     }
@@ -755,9 +789,15 @@ PythonQtImport::getModuleCode(PythonQtImporter *self, const char* fullname, QStr
     PyObject *code = nullptr;
     test = path + zso->suffix;
 
-    if (Py_VerboseFlag > 1)
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+    if (Py_VerboseFlag > 1) {
+#else
+    PyObject* verbose_flag = PySys_GetObject("verbose");
+    if (verbose_flag && PyLong_AsLong(verbose_flag) > 1) {
+#endif
       PySys_WriteStderr("# trying %s\n",
                         QStringToPythonConstCharPointer(test));
+    }
     if (PythonQt::importInterface()->exists(test)) {
       time_t mtime = 0;
       int ispackage = zso->type & IS_PACKAGE;
@@ -864,7 +904,24 @@ void PythonQtImport::init()
   mlab_searchorder[0].suffix[0] = SEP;
   mlab_searchorder[1].suffix[0] = SEP;
   mlab_searchorder[2].suffix[0] = SEP;
-  if (Py_OptimizeFlag) {
+#if PY_VERSION_HEX < 0x030B0000  // Python < 3.11
+    if (Py_OptimizeFlag) {
+#else
+  const bool do_optimize = []() -> bool
+  {
+    PyObject* flags = PySys_GetObject("flags");
+    if (flags) {
+      PyObject* optimize = PyObject_GetAttrString(flags, "optimize");
+      if (optimize && PyLong_AsLong(optimize) > 0)
+      {
+        return true;
+      }
+      Py_XDECREF(optimize);
+    }
+    return false;
+  } ();
+  if (do_optimize) {
+#endif
     /* Reverse *.pyc and *.pyo */
     struct st_mlab_searchorder tmp;
     tmp = mlab_searchorder[0];