PyPySide: Encapsulate type generation to be PyPy compatible

Type generation in PyPy is critical. When type creation calls
PyType_Ready, PyPy freezes the current state of the type object.
That has fatal effects, because with the Limited API, we need
to patch some types a little _after_ creation.

The functionality of this patch is still the same, but type
creation is totally encapsulated, and we can do a different
implementation for PyPy.

[ChangeLog][PySide6] PyPySide: Type creation was completely
encapsulated. The implementation can now be rewritten for PyPy.

Task-number: PYSIDE-535
Change-Id: Iae0cadb15b631344ae76cea8c104d4b69941c2b0
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

10 files changed, 212 insertions, 83 deletions

diff --git a/sources/pyside6/libpyside/class_property.cpp b/sources/pyside6/libpyside/class_property.cpp
index 63850be07..74ee79e4d 100644
--- a/sources/pyside6/libpyside/class_property.cpp
+++ b/sources/pyside6/libpyside/class_property.cpp
@@ -92,7 +92,7 @@ static PyType_Slot PyClassProperty_slots[] = {
 };
 
 static PyType_Spec PyClassProperty_spec = {
-    "PySide6.QtCore.PyClassProperty",
+    "2:PySide6.QtCore.PyClassProperty",
     sizeof(propertyobject),
     0,
     Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE,
@@ -105,8 +105,7 @@ PyTypeObject *PyClassPropertyTypeF()
     if (type == nullptr) {
         // Provide the same `tp_getset`, which is not inherited.
         PyClassProperty_slots[0].pfunc = PyProperty_Type.tp_getset;
-        type = reinterpret_cast<PyTypeObject *>(
-            PyType_FromSpec(&PyClassProperty_spec));
+        type = SbkType_FromSpec(&PyClassProperty_spec);
     }
     return type;
 }
diff --git a/sources/pyside6/libpyside/pysideproperty.cpp b/sources/pyside6/libpyside/pysideproperty.cpp
index 70c59a89a..9f9340e19 100644
--- a/sources/pyside6/libpyside/pysideproperty.cpp
+++ b/sources/pyside6/libpyside/pysideproperty.cpp
@@ -106,7 +106,7 @@ static PyType_Slot PySidePropertyType_slots[] = {
     {Py_tp_getset, PySidePropertyType_getset},
     {0, nullptr}
 };
-// Dotted modulename is crucial for SbkType_FromSpec to work. Is this name right?
+
 static PyType_Spec PySidePropertyType_spec = {
     "2:PySide6.QtCore.Property",
     sizeof(PySideProperty),
diff --git a/sources/pyside6/libpyside/pysidesignal.cpp b/sources/pyside6/libpyside/pysidesignal.cpp
index 2ecae7287..842311fae 100644
--- a/sources/pyside6/libpyside/pysidesignal.cpp
+++ b/sources/pyside6/libpyside/pysidesignal.cpp
@@ -165,14 +165,7 @@ static PyType_Spec PySideSignalType_spec = {
 
 PyTypeObject *PySideSignalTypeF(void)
 {
-    static PyTypeObject *type = nullptr;
-    if (!type) {
-        type = reinterpret_cast<PyTypeObject *>(SbkType_FromSpec(&PySideSignalType_spec));
-        PyTypeObject *hold = Py_TYPE(type);
-        Py_TYPE(type) = PySideMetaSignalTypeF();
-        Py_INCREF(Py_TYPE(type));
-        Py_DECREF(hold);
-    }
+    static auto *type = SbkType_FromSpecWithMeta(&PySideSignalType_spec, PySideMetaSignalTypeF());
     return type;
 }
 
diff --git a/sources/shiboken6/libshiboken/CMakeLists.txt b/sources/shiboken6/libshiboken/CMakeLists.txt
index b07f305a1..3e1b14594 100644
--- a/sources/shiboken6/libshiboken/CMakeLists.txt
+++ b/sources/shiboken6/libshiboken/CMakeLists.txt
@@ -54,6 +54,7 @@ sbkfeature_base.cpp
 sbkmodule.cpp
 sbkstring.cpp
 sbkstaticstrings.cpp
+sbktypefactory.cpp
 bindingmanager.cpp
 threadstatesaver.cpp
 shibokenbuffer.cpp
@@ -136,6 +137,7 @@ install(FILES
         sbkmodule.h
         sbkstring.h
         sbkstaticstrings.h
+        sbktypefactory.h
         shiboken.h
         shibokenmacros.h
         threadstatesaver.h
diff --git a/sources/shiboken6/libshiboken/basewrapper.cpp b/sources/shiboken6/libshiboken/basewrapper.cpp
index f72951dd1..0c2ac950e 100644
--- a/sources/shiboken6/libshiboken/basewrapper.cpp
+++ b/sources/shiboken6/libshiboken/basewrapper.cpp
@@ -251,14 +251,12 @@ static const char *SbkObject_SignatureStrings[] = {
 
 PyTypeObject *SbkObject_TypeF(void)
 {
-    static PyTypeObject *type = nullptr;
-    if (!type) {
-        type = reinterpret_cast<PyTypeObject *>(SbkType_FromSpec(&SbkObject_Type_spec));
-        Py_TYPE(type) = SbkObjectType_TypeF();
-        Py_INCREF(Py_TYPE(type));
-        type->tp_weaklistoffset = offsetof(SbkObject, weakreflist);
-        type->tp_dictoffset = offsetof(SbkObject, ob_dict);
-    }
+    static auto *type = SbkType_FromSpec_BMDWB(&SbkObject_Type_spec,
+                                               nullptr,     // bases
+                                               SbkObjectType_TypeF(),
+                                               offsetof(SbkObject, ob_dict),
+                                               offsetof(SbkObject, weakreflist),
+                                               nullptr);    // bufferprocs
     return type;
 }
 
@@ -606,51 +604,6 @@ PyObject *SbkDummyNew(PyTypeObject *type, PyObject *, PyObject *)
     return nullptr;
 }
 
-PyTypeObject *SbkType_FromSpec(PyType_Spec *spec)
-{
-    return SbkType_FromSpecWithBases(spec, nullptr);
-}
-
-PyTypeObject *SbkType_FromSpecWithBases(PyType_Spec *spec, PyObject *bases)
-{
-    // PYSIDE-1286: Generate correct __module__ and __qualname__
-    // The name field can now be extended by an "n:" prefix which is
-    // the number of modules in the name. The default is 1.
-    //
-    // Example:
-    //    "2:mainmod.submod.mainclass.subclass"
-    // results in
-    //    __module__   : "mainmod.submod"
-    //    __qualname__ : "mainclass.subclass"
-    //    __name__     : "subclass"
-
-    PyType_Spec new_spec = *spec;
-    const char *colon = strchr(spec->name, ':');
-    assert(colon);
-    int package_level = atoi(spec->name);
-    const char *mod = new_spec.name = colon + 1;
-
-    PyObject *obType = PyType_FromSpecWithBases(&new_spec, bases);
-    if (obType == nullptr)
-        return nullptr;
-
-    const char *qual = mod;
-    for (int idx = package_level; idx > 0; --idx) {
-        const char *dot = strchr(qual, '.');
-        if (!dot)
-            break;
-        qual = dot + 1;
-    }
-    int mlen = qual - mod - 1;
-    Shiboken::AutoDecRef module(Shiboken::String::fromCString(mod, mlen));
-    Shiboken::AutoDecRef qualname(Shiboken::String::fromCString(qual));
-    if (PyObject_SetAttr(obType, Shiboken::PyMagicName::module(), module) < 0)
-        return nullptr;
-    if (PyObject_SetAttr(obType, Shiboken::PyMagicName::qualname(), qualname) < 0)
-        return nullptr;
-    return reinterpret_cast<PyTypeObject *>(obType);
-}
-
 // PYSIDE-74: Fallback used in all types now.
 PyObject *FallbackRichCompare(PyObject *self, PyObject *other, int op)
 {
@@ -930,10 +883,7 @@ introduceWrapperType(PyObject *enclosingObject,
 {
     typeSpec->slots[0].pfunc = reinterpret_cast<void *>(baseType ? baseType : SbkObject_TypeF());
 
-    auto *heaptype = SbkType_FromSpecWithBases(typeSpec, baseTypes);
-    Py_TYPE(heaptype) = SbkObjectType_TypeF();
-    Py_INCREF(Py_TYPE(heaptype));
-    auto *type = reinterpret_cast<PyTypeObject *>(heaptype);
+    auto *type = SbkType_FromSpecBasesMeta(typeSpec, baseTypes, SbkObjectType_TypeF());
     if (baseType) {
         if (baseTypes) {
             for (int i = 0; i < PySequence_Fast_GET_SIZE(baseTypes); ++i) {
diff --git a/sources/shiboken6/libshiboken/basewrapper.h b/sources/shiboken6/libshiboken/basewrapper.h
index 010870f55..2c8da098f 100644
--- a/sources/shiboken6/libshiboken/basewrapper.h
+++ b/sources/shiboken6/libshiboken/basewrapper.h
@@ -42,6 +42,7 @@
 
 #include "sbkpython.h"
 #include "shibokenmacros.h"
+#include "sbktypefactory.h"
 
 #include <vector>
 #include <string>
@@ -130,17 +131,13 @@ LIBSHIBOKEN_API PyObject *MakeQAppWrapper(PyTypeObject *type);
  *  PYSIDE-832: Use object_dealloc instead of nullptr.
  *
  *  When moving to heaptypes, we were struck by a special default behavior of
- *  PyType_FromSpecWithBases that inserts subtype_dealloc when tp_dealloc is
+ *  PyType_FromSpec that inserts subtype_dealloc when tp_dealloc is
  *  nullptr. But the default before conversion to heaptypes was to assign
  *  object_dealloc. This seems to be a bug in the Limited API.
  */
 /// PYSIDE-939: Replaced by Sbk_object_dealloc.
 LIBSHIBOKEN_API PyObject *SbkDummyNew(PyTypeObject *type, PyObject *, PyObject *);
 
-/// PYSIDE-1286: Generate correct __module__ and __qualname__
-LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpec(PyType_Spec *);
-LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpecWithBases(PyType_Spec *, PyObject *);
-
 /// PYSIDE-74: Fallback used in all types now.
 LIBSHIBOKEN_API PyObject *FallbackRichCompare(PyObject *self, PyObject *other, int op);
 
diff --git a/sources/shiboken6/libshiboken/sbkenum.cpp b/sources/shiboken6/libshiboken/sbkenum.cpp
index bf9c80303..a6f65c7ab 100644
--- a/sources/shiboken6/libshiboken/sbkenum.cpp
+++ b/sources/shiboken6/libshiboken/sbkenum.cpp
@@ -675,7 +675,7 @@ newTypeWithName(const char *name,
     PyType_Slot newslots[99] = {};  // enough but not too big for the stack
     PyType_Spec newspec;
     DeclaredEnumTypes::EnumEntry entry{strdup(name), nullptr};
-    newspec.name = entry.name; // Note that SbkType_FromSpecWithBases might use a substring.
+    newspec.name = entry.name; // Note that SbkType_FromSpec might use a substring.
     newspec.basicsize = SbkNewEnum_spec.basicsize;
     newspec.itemsize = SbkNewEnum_spec.itemsize;
     newspec.flags = SbkNewEnum_spec.flags;
@@ -693,9 +693,8 @@ newTypeWithName(const char *name,
     static auto basetype = reinterpret_cast<PyObject *>(SbkEnum_TypeF());
     Py_INCREF(basetype);
     PyTuple_SetItem(bases, 0, basetype);
-    auto *type = SbkType_FromSpecWithBases(&newspec, bases);
-    entry.type = reinterpret_cast<PyTypeObject *>(type);
-    Py_TYPE(type) = SbkEnumType_TypeF();
+    auto *type = SbkType_FromSpecBasesMeta(&newspec, bases, SbkEnumType_TypeF());
+    entry.type = type;
 
     auto *enumType = reinterpret_cast<SbkEnumType *>(type);
     auto *setp = PepType_SETP(enumType);
diff --git a/sources/shiboken6/libshiboken/sbktypefactory.cpp b/sources/shiboken6/libshiboken/sbktypefactory.cpp
new file mode 100644
index 000000000..bdde7598f
--- /dev/null
+++ b/sources/shiboken6/libshiboken/sbktypefactory.cpp
@@ -0,0 +1,130 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "sbktypefactory.h"
+#include "shiboken.h"
+
+extern "C"
+{
+
+PyTypeObject *SbkType_FromSpec(PyType_Spec *spec)
+{
+    return SbkType_FromSpec_BMDWB(spec, nullptr, nullptr, 0, 0, nullptr);
+}
+
+PyTypeObject *SbkType_FromSpecWithMeta(PyType_Spec *spec, PyTypeObject *meta)
+{
+    return SbkType_FromSpec_BMDWB(spec, nullptr, meta, 0, 0, nullptr);
+}
+
+PyTypeObject *SbkType_FromSpecWithBases(PyType_Spec *spec, PyObject *bases)
+{
+    return SbkType_FromSpec_BMDWB(spec, bases, nullptr, 0, 0, nullptr);
+}
+
+PyTypeObject *SbkType_FromSpecBasesMeta(PyType_Spec *spec, PyObject *bases, PyTypeObject *meta)
+{
+    return SbkType_FromSpec_BMDWB(spec, bases, meta, 0, 0, nullptr);
+}
+
+PyTypeObject *SbkType_FromSpec_BMDWB(PyType_Spec *spec,
+                                     PyObject *bases,
+                                     PyTypeObject *meta,
+                                     int dictoffset,
+                                     int weaklistoffset,
+                                     PyBufferProcs *bufferprocs)
+{
+    // PYSIDE-1286: Generate correct __module__ and __qualname__
+    // The name field can now be extended by an "n:" prefix which is
+    // the number of modules in the name. The default is 1.
+    //
+    // Example:
+    //    "2:mainmod.submod.mainclass.subclass"
+    // results in
+    //    __module__   : "mainmod.submod"
+    //    __qualname__ : "mainclass.subclass"
+    //    __name__     : "subclass"
+
+    PyType_Spec new_spec = *spec;
+    const char *colon = strchr(spec->name, ':');
+    assert(colon);
+    int package_level = atoi(spec->name);
+    const char *mod = new_spec.name = colon + 1;
+
+    PyObject *obType = PyType_FromSpecWithBases(&new_spec, bases);
+    if (obType == nullptr)
+        return nullptr;
+
+    const char *qual = mod;
+    for (int idx = package_level; idx > 0; --idx) {
+        const char *dot = strchr(qual, '.');
+        if (!dot)
+            break;
+        qual = dot + 1;
+    }
+    int mlen = qual - mod - 1;
+    Shiboken::AutoDecRef module(Shiboken::String::fromCString(mod, mlen));
+    Shiboken::AutoDecRef qualname(Shiboken::String::fromCString(qual));
+    if (PyObject_SetAttr(obType, Shiboken::PyMagicName::module(), module) < 0)
+        return nullptr;
+    if (PyObject_SetAttr(obType, Shiboken::PyMagicName::qualname(), qualname) < 0)
+        return nullptr;
+
+    auto *type = reinterpret_cast<PyTypeObject *>(obType);
+
+    if (meta) {
+        PyTypeObject *hold = Py_TYPE(type);
+        Py_TYPE(type) = meta;
+        Py_INCREF(Py_TYPE(type));
+        if (hold->tp_flags & Py_TPFLAGS_HEAPTYPE)
+            Py_DECREF(hold);
+    }
+
+    if (dictoffset)
+        type->tp_dictoffset = dictoffset;
+    if (weaklistoffset)
+        type->tp_weaklistoffset = weaklistoffset;
+    if (bufferprocs)
+        PepType_AS_BUFFER(type) = bufferprocs;
+
+    PyType_Modified(type);
+    return type;
+}
+
+} //extern "C"
diff --git a/sources/shiboken6/libshiboken/sbktypefactory.h b/sources/shiboken6/libshiboken/sbktypefactory.h
new file mode 100644
index 000000000..092c168b6
--- /dev/null
+++ b/sources/shiboken6/libshiboken/sbktypefactory.h
@@ -0,0 +1,61 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef SBKTYPEFACTORY_H
+#define SBKTYPEFACTORY_H
+
+#include "sbkpython.h"
+
+extern "C"
+{
+
+LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpec(PyType_Spec *);
+LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpecWithMeta(PyType_Spec *, PyTypeObject *);
+LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpecWithBases(PyType_Spec *, PyObject *);
+LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpecBasesMeta(PyType_Spec *, PyObject *, PyTypeObject *);
+LIBSHIBOKEN_API PyTypeObject *SbkType_FromSpec_BMDWB(PyType_Spec *spec,
+                                                     PyObject *bases,
+                                                     PyTypeObject *meta,
+                                                     int dictoffset,
+                                                     int weaklistoffset,
+                                                     PyBufferProcs *bufferprocs);
+
+} //extern "C"
+
+#endif // SBKTYPEFACTORY_H
diff --git a/sources/shiboken6/libshiboken/voidptr.cpp b/sources/shiboken6/libshiboken/voidptr.cpp
index ff6f6cfd5..f0161d282 100644
--- a/sources/shiboken6/libshiboken/voidptr.cpp
+++ b/sources/shiboken6/libshiboken/voidptr.cpp
@@ -318,11 +318,9 @@ static PyType_Spec SbkVoidPtrType_spec = {
 
 PyTypeObject *SbkVoidPtrTypeF(void)
 {
-    static PyTypeObject *type = nullptr;
-    if (!type) {
-        type = SbkType_FromSpec(&SbkVoidPtrType_spec);
-        PepType_AS_BUFFER(type) = &SbkVoidPtrObjectBufferProc;
-    }
+    static PyTypeObject *type = SbkType_FromSpec_BMDWB(&SbkVoidPtrType_spec,
+                                                       nullptr, nullptr, 0, 0,
+                                                       &SbkVoidPtrObjectBufferProc);
     return type;
 }