PyEnum: Remove the old duplication of Enums in the enclosing scope

When implementing Python enums, the behavior of old Qt enums
was copied: Every enum was also inserted into the enclosing scope.

This patch removes that for two reasons:

- it is inconsequent to keep an old quirk when we have all
  enums renewed so much

- It is more consistent compared to our competitor

- it is a prerequisite to implement efficient lazy initialization

PROBLEM: Many constants (about 110) are no longer recognized, for
instance   `Qt.AlignLeft`  should be `Qt.AlignmentFlag.AlignLeft`.
The question is if that can be fixed easily in C++, or if
the file mapping.py should get ~100 new fixes?

SOLUTION: We allow the old enums, but tell nobody that they continue
to work. They also are not advertized in the PYI files.

[ChangeLog][PySide6] The duplication of enum values into the
enclosing scope, allowing to write Qt.AlignLeft instead of
Qt.Alignment.AlignLeft, is still implemented but no longer
advertized in PYI files or line completion.

Task-number: PYSIDE-1735
Change-Id: I79a90d08f2a5a3a069fa551e60d609ecad718239
Pick-to: 6.3
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

8 files changed, 70 insertions, 19 deletions

diff --git a/sources/pyside6/tests/QtCore/qinstallmsghandler_test.py b/sources/pyside6/tests/QtCore/qinstallmsghandler_test.py
index 56bec5e65..9c5ae4370 100644
--- a/sources/pyside6/tests/QtCore/qinstallmsghandler_test.py
+++ b/sources/pyside6/tests/QtCore/qinstallmsghandler_test.py
@@ -12,9 +12,9 @@ sys.path.append(os.fspath(Path(__file__).resolve().parents[1]))
 from init_paths import init_test_paths
 init_test_paths(False)
 
-from PySide6.QtCore import (QLibraryInfo, QtCriticalMsg, QtDebugMsg, QtInfoMsg,
+from PySide6.QtCore import (QLibraryInfo, QtMsgType,
                             QMessageLogContext,
-                            QtWarningMsg, qCritical, qFormatLogMessage, qDebug,
+                            qCritical, qFormatLogMessage, qDebug,
                             qInstallMessageHandler, qWarning)
 
 
@@ -56,18 +56,18 @@ class QInstallMsgHandlerTest(unittest.TestCase):
         rethandler = qInstallMessageHandler(handler)
         if QLibraryInfo.isDebugBuild():
             qDebug("Test Debug")
-            self.assertEqual(param[0], QtDebugMsg)
+            self.assertEqual(param[0], QtMsgType.QtDebugMsg)
             self.assertEqual(param[2], "Test Debug")
         qWarning("Test Warning")
-        self.assertEqual(param[0], QtWarningMsg)
+        self.assertEqual(param[0], QtMsgType.QtWarningMsg)
         self.assertEqual(param[2], "Test Warning")
         qCritical("Test Critical")
-        self.assertEqual(param[0], QtCriticalMsg)
+        self.assertEqual(param[0], QtMsgType.QtCriticalMsg)
         self.assertEqual(param[2], "Test Critical")
 
     def testFormat(self):
         ctx = QMessageLogContext()
-        s = qFormatLogMessage(QtInfoMsg, ctx, 'bla')
+        s = qFormatLogMessage(QtMsgType.QtInfoMsg, ctx, 'bla')
         self.assertTrue(s)
 
 
diff --git a/sources/shiboken6/libshiboken/sbkenum.cpp b/sources/shiboken6/libshiboken/sbkenum.cpp
index b9427142d..3f432dcb2 100644
--- a/sources/shiboken6/libshiboken/sbkenum.cpp
+++ b/sources/shiboken6/libshiboken/sbkenum.cpp
@@ -618,7 +618,7 @@ bool createGlobalEnumItem(PyTypeObject *enumType, PyObject *module, const char *
     PyObject *enumItem = createEnumItem(enumType, itemName, itemValue);
     if (!enumItem)
         return false;
-    int ok = PyModule_AddObject(module, itemName, enumItem);
+    int ok = useOldEnum ? PyModule_AddObject(module, itemName, enumItem) : true;
     Py_DECREF(enumItem);
     return ok >= 0;
 }
@@ -629,7 +629,7 @@ bool createScopedEnumItem(PyTypeObject *enumType, PyTypeObject *scope,
     PyObject *enumItem = createEnumItem(enumType, itemName, itemValue);
     if (!enumItem)
         return false;
-    int ok = PyDict_SetItemString(scope->tp_dict, itemName, enumItem);
+    int ok = useOldEnum ? PyDict_SetItemString(scope->tp_dict, itemName, enumItem) : true;
     Py_DECREF(enumItem);
     return ok >= 0;
 }
@@ -995,13 +995,6 @@ PyTypeObject *morphLastEnumToPython()
     PyObject_SetAttr(obNewType, PyMagicName::qualname(), qual_name);
     AutoDecRef module(PyObject_GetAttr(obEnumType, PyMagicName::module()));
     PyObject_SetAttr(obNewType, PyMagicName::module(), module);
-    // As a last step, fix the item entries in the enclosing object.
-    pos = 0;
-    while (PyDict_Next(values, &pos, &key, &value)) {
-        AutoDecRef entry(PyObject_GetAttr(obNewType, key));
-        if (PyObject_SetAttr(lec.scopeOrModule, key, entry) < 0)
-            return nullptr;
-    }
     // Protect against double initialization
     setp->replacementType = newType;
 #if PY_VERSION_HEX < 0x03080000
diff --git a/sources/shiboken6/libshiboken/sbkfeature_base.cpp b/sources/shiboken6/libshiboken/sbkfeature_base.cpp
index 2b3eba19e..e191204e4 100644
--- a/sources/shiboken6/libshiboken/sbkfeature_base.cpp
+++ b/sources/shiboken6/libshiboken/sbkfeature_base.cpp
@@ -4,6 +4,7 @@
 #include "basewrapper.h"
 #include "basewrapper_p.h"
 #include "autodecref.h"
+#include "sbkenum_p.h"
 #include "sbkstring.h"
 #include "sbkstaticstrings.h"
 #include "sbkstaticstrings_p.h"
@@ -23,8 +24,8 @@ extern "C"
 // Maybe the same function from feature_select.cpp will be replaced.
 //
 
-static PyObject *cached_globals = nullptr;
-static PyObject *last_select_id = nullptr;
+static PyObject *cached_globals{};
+static PyObject *last_select_id{};
 
 PyObject *getFeatureSelectId()
 {
@@ -86,9 +87,54 @@ PyObject *mangled_type_getattro(PyTypeObject *type, PyObject *name)
      * What we change here is the meta class of `QObject`.
      */
     static getattrofunc type_getattro = PyType_Type.tp_getattro;
+    static PyObject *ignAttr1 = PyName::qtStaticMetaObject();
+    static PyObject *ignAttr2 = PyMagicName::get();
     if (SelectFeatureSet != nullptr)
         type->tp_dict = SelectFeatureSet(type);
-    return type_getattro(reinterpret_cast<PyObject *>(type), name);
+    auto *ret = type_getattro(reinterpret_cast<PyObject *>(type), name);
+
+    // PYSIDE-1735: Be forgiving with strict enums and fetch the enum, silently.
+    //              The PYI files now look correct, but the old duplication is
+    //              emulated here. This should be removed in Qt 7, see `parser.py`.
+    //
+    // FIXME PYSIDE7 should remove this forgivingness:
+    //
+    //      The duplication of enum values into the enclosing scope, allowing to write
+    //      Qt.AlignLeft instead of Qt.Alignment.AlignLeft, is still implemented but
+    //      no longer advertized in PYI files or line completion.
+
+    if (!ret && name != ignAttr1 && name != ignAttr2) {
+        PyObject *error_type, *error_value, *error_traceback;
+        PyErr_Fetch(&error_type, &error_value, &error_traceback);
+
+        // This is similar to `find_name_in_mro`, but instead of looking directly into
+        // tp_dict, we search for the attribute in local classes of that dict.
+        PyObject *mro = type->tp_mro;
+        assert(PyTuple_Check(mro));
+        size_t idx, n = PyTuple_GET_SIZE(mro);
+        for (idx = 0; idx < n; ++idx) {
+            // FIXME This loop should further be optimized by installing an extra
+            //       <classname>_EnumInfo structure. This comes with the next compatibility patch.
+            auto *base = PyTuple_GET_ITEM(mro, idx);
+            auto *type_base = reinterpret_cast<PyTypeObject *>(base);
+            auto *dict = type_base->tp_dict;
+            PyObject *key, *value;
+            Py_ssize_t pos = 0;
+            while (PyDict_Next(dict, &pos, &key, &value)) {
+                static auto *EnumMeta = getPyEnumMeta();
+                if (Py_TYPE(value) == EnumMeta) {
+                    auto *valtype = reinterpret_cast<PyTypeObject *>(value);
+                    auto *result = PyDict_GetItem(valtype->tp_dict, name);
+                    if (result) {
+                        Py_INCREF(result);
+                        return result;
+                    }
+                }
+            }
+        }
+        PyErr_Restore(error_type, error_value, error_traceback);
+    }
+    return ret;
 }
 
 PyObject *Sbk_TypeGet___dict__(PyTypeObject *type, void *context)
diff --git a/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/parser.py b/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/parser.py
index 5dabc395f..4c8ade025 100644
--- a/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/parser.py
+++ b/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/parser.py
@@ -62,7 +62,6 @@ def _get_flag_enum_option():
             flag = bool(int(opt))
     elif hasattr(sys, sysname):
         flag = bool(getattr(sys, sysname))
-    sysver = sys.version_info[:2]
     # PYSIDE-1797: Emit a warning when we may remove pep384_issue33738.cpp
     if pyminver and pyminver >= (3, 8):
         warnings.warn(f"\n    *** Python is at version {'.'.join(map(str, pyminver))} now. "
@@ -71,6 +70,10 @@ def _get_flag_enum_option():
     if pymaxver and pymaxver > (3, 10):
         warnings.warn(f"\n    *** Python is at version {'.'.join(map(str, pymaxver))} now. "
                       f"Please check if enum_310.py should be updated! ***")
+    # PYSIDE-1735: Emit a warning when we may update enum_310.py
+    if ver[:2] >= (7, 0):
+        warnings.warn(f"\n    *** PySide is at version {'.'.join(map(str, ver[:2]))} now. "
+                      f"Please drop the forgiving Enum behavior in `mangled_type_getattro` ***")
     # modify the sys attribute to bool
     setattr(sys, sysname, flag)
     # modify the env attribute to "0" or "1"
diff --git a/sources/shiboken6/tests/samplebinding/derived_test.py b/sources/shiboken6/tests/samplebinding/derived_test.py
index 897b1654e..2d5eb4293 100644
--- a/sources/shiboken6/tests/samplebinding/derived_test.py
+++ b/sources/shiboken6/tests/samplebinding/derived_test.py
@@ -40,6 +40,7 @@ class DerivedTest(unittest.TestCase):
                                  'id_', 'pureVirtual', 'unpureVirtual'])
         self.assertTrue(inherited_methods.issubset(dir(Derived)))
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testOverloadedMethodCall(self):
         '''Test if the correct overloaded method is being called.'''
         derived = Derived()
@@ -56,6 +57,7 @@ class DerivedTest(unittest.TestCase):
         self.assertEqual(type(result), OverloadedFuncEnum)
         self.assertEqual(result, sample.OverloadedFunc_d)
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testOtherOverloadedMethodCall(self):
         '''Another test to check overloaded method calling, just to double check.'''
         derived = Derived()
@@ -68,6 +70,7 @@ class DerivedTest(unittest.TestCase):
         self.assertEqual(type(result), Derived.OtherOverloadedFuncEnum)
         self.assertEqual(result, Derived.OtherOverloadedFunc_id)
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testOverloadedMethodCallWithDifferentNumericTypes(self):
         '''Test if the correct overloaded method accepts a different numeric type as argument.'''
         derived = Derived()
diff --git a/sources/shiboken6/tests/samplebinding/enumfromremovednamespace_test.py b/sources/shiboken6/tests/samplebinding/enumfromremovednamespace_test.py
index 8cf21d4ff..f70621c59 100644
--- a/sources/shiboken6/tests/samplebinding/enumfromremovednamespace_test.py
+++ b/sources/shiboken6/tests/samplebinding/enumfromremovednamespace_test.py
@@ -21,6 +21,8 @@ from shibokensupport.signature import get_signature
 
 
 class TestEnumFromRemovedNamespace(unittest.TestCase):
+
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testEnumPromotedToGlobal(self):
         sample.RemovedNamespace1_Enum
         self.assertEqual(sample.RemovedNamespace1_Enum_Value0, 0)
diff --git a/sources/shiboken6/tests/samplebinding/modifications_test.py b/sources/shiboken6/tests/samplebinding/modifications_test.py
index 478e0700d..d1e70004f 100644
--- a/sources/shiboken6/tests/samplebinding/modifications_test.py
+++ b/sources/shiboken6/tests/samplebinding/modifications_test.py
@@ -41,6 +41,7 @@ class ModificationsTest(unittest.TestCase):
         # PYSIDE-535: Need to collect garbage in PyPy to trigger deletion
         gc.collect()
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testClassMembersAvailability(self):
         '''Test if Modified class really have the expected members.'''
         expected_members = set(['OverloadedModFunc', 'OverloadedNone',
diff --git a/sources/shiboken6/tests/samplebinding/sample_test.py b/sources/shiboken6/tests/samplebinding/sample_test.py
index 35595649d..52abc968f 100644
--- a/sources/shiboken6/tests/samplebinding/sample_test.py
+++ b/sources/shiboken6/tests/samplebinding/sample_test.py
@@ -18,6 +18,7 @@ import sample
 class ModuleTest(unittest.TestCase):
     '''Test case for module and global functions'''
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testModuleMembers(self):
         '''Test availability of classes, global functions and other members on binding'''
         expected_members = set(['Abstract', 'Derived', 'Point',
@@ -30,12 +31,14 @@ class ModuleTest(unittest.TestCase):
                                 'GlobalEnum', 'NoThing'])
         self.assertTrue(expected_members.issubset(dir(sample)))
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testAbstractPrintFormatEnum(self):
         '''Test availability of PrintFormat enum from Abstract class'''
         enum_members = set(['PrintFormat', 'Short', 'Verbose',
                             'OnlyId', 'ClassNameAndId'])
         self.assertTrue(enum_members.issubset(dir(sample.Abstract)))
 
+    @unittest.skipIf(sys.pyside63_option_python_enum, "Makes no sense with strict Enums")
     def testSampleNamespaceOptionEnum(self):
         '''Test availability of Option enum from SampleNamespace namespace'''
         enum_members = set(['Option', 'None_', 'RandomNumber', 'UnixTime'])