Shiboken: Simplify Python Error Messages

The function PyErr_SetString is used quite often, which has
no return value. The bracketed sequence

    PyErr_SetString(...);
    return nullptr;

can in most cases be replaced by a single call to

    return PyErr_Format(...);

To simplify matters, PyErr_Format is now used everywhere.

Task-number: PYSIDE-2404
Change-Id: I5988fcd2430be700415d14d7a5cc740211e61d08
Pick-to: 6.7
Reviewed-by: Adrian Herrmann <adrian.herrmann@qt.io>

11 files changed, 59 insertions, 112 deletions

diff --git a/sources/pyside6/PySide6/QtCore/glue/core_snippets.cpp b/sources/pyside6/PySide6/QtCore/glue/core_snippets.cpp
index 4266e868c..f6acf9d60 100644
--- a/sources/pyside6/PySide6/QtCore/glue/core_snippets.cpp
+++ b/sources/pyside6/PySide6/QtCore/glue/core_snippets.cpp
@@ -340,9 +340,7 @@ PyObject *invokeMetaMethodWithReturn(const InvokeMetaMethodFuncWithReturn &f,
                               a6.toGenericArgument(), a7.toGenericArgument(), a8.toGenericArgument(),
                               a9.toGenericArgument());
     PyEval_RestoreThread(_save); // Py_END_ALLOW_THREADS
-    if (!callResult) {
-        PyErr_SetString(PyExc_RuntimeError, "QMetaMethod invocation failed.");
-        return nullptr;
-    }
+    if (!callResult)
+        return PyErr_Format(PyExc_RuntimeError, "QMetaMethod invocation failed.");
     return convertGenericReturnArgument(r.data(), r.metaType());
 }
diff --git a/sources/pyside6/PySide6/QtQml/pysideqmlvolatilebool.cpp b/sources/pyside6/PySide6/QtQml/pysideqmlvolatilebool.cpp
index 6e403ab72..52a45e026 100644
--- a/sources/pyside6/PySide6/QtQml/pysideqmlvolatilebool.cpp
+++ b/sources/pyside6/PySide6/QtQml/pysideqmlvolatilebool.cpp
@@ -63,10 +63,8 @@ QtQml_VolatileBoolObject_set(QtQml_VolatileBoolObject *self, PyObject *args)
     }
 
     ok = PyObject_IsTrue(value);
-    if (ok < 0) {
-        PyErr_SetString(PyExc_TypeError, "Not a boolean value.");
-        return nullptr;
-    }
+    if (ok < 0)
+        return PyErr_Format(PyExc_TypeError, "Not a boolean value.");
 
     *self->flag = ok > 0;
 
diff --git a/sources/pyside6/PySide6/glue/qtcore.cpp b/sources/pyside6/PySide6/glue/qtcore.cpp
index bc51d26d7..a8afc9b6a 100644
--- a/sources/pyside6/PySide6/glue/qtcore.cpp
+++ b/sources/pyside6/PySide6/glue/qtcore.cpp
@@ -632,20 +632,16 @@ if (ret == nullptr) {
 // @snippet qbytearray-mgetitem
 if (PyIndex_Check(_key)) {
     const Py_ssize_t _i = PyNumber_AsSsize_t(_key, PyExc_IndexError);
-    if (_i < 0 || _i >= %CPPSELF.size()) {
-        PyErr_SetString(PyExc_IndexError, "index out of bounds");
-        return nullptr;
-    }
+    if (_i < 0 || _i >= %CPPSELF.size())
+        return PyErr_Format(PyExc_IndexError, "index out of bounds");
     char res[2] = {%CPPSELF.at(_i), '\0'};
     return PyBytes_FromStringAndSize(res, 1);
 }
 
-if (PySlice_Check(_key) == 0) {
-    PyErr_Format(PyExc_TypeError,
+if (PySlice_Check(_key) == 0)
+    return PyErr_Format(PyExc_TypeError,
                  "list indices must be integers or slices, not %.200s",
                  Py_TYPE(_key)->tp_name);
-    return nullptr;
-}
 
 Py_ssize_t start, stop, step, slicelength;
 if (PySlice_GetIndicesEx(_key, %CPPSELF.size(), &start, &stop, &step, &slicelength) < 0)
diff --git a/sources/pyside6/PySide6/glue/qtgui.cpp b/sources/pyside6/PySide6/glue/qtgui.cpp
index 130de11bb..5c860a2bf 100644
--- a/sources/pyside6/PySide6/glue/qtgui.cpp
+++ b/sources/pyside6/PySide6/glue/qtgui.cpp
@@ -912,10 +912,8 @@ return %CPPSELF.rectCount();
 // @snippet qregion-len
 
 // @snippet qregion-getitem
-if (_i < 0 || _i >= %CPPSELF.rectCount()) {
-    PyErr_SetString(PyExc_IndexError, "index out of bounds");
-    return nullptr;
-}
+if (_i < 0 || _i >= %CPPSELF.rectCount())
+    return PyErr_Format(PyExc_IndexError, "index out of bounds");
 
 const QRect cppResult = *(%CPPSELF.cbegin() + _i);
 return %CONVERTTOPYTHON[QRect](cppResult);
diff --git a/sources/pyside6/PySide6/glue/qtuitools.cpp b/sources/pyside6/PySide6/glue/qtuitools.cpp
index 0f4405944..1835ed096 100644
--- a/sources/pyside6/PySide6/glue/qtuitools.cpp
+++ b/sources/pyside6/PySide6/glue/qtuitools.cpp
@@ -45,7 +45,7 @@ static PyObject *QUiLoadedLoadUiFromDevice(QUiLoader *self, QIODevice *dev, QWid
     }
 
     if (!PyErr_Occurred())
-        PyErr_SetString(PyExc_RuntimeError, "Unable to open/read ui device");
+        PyErr_Format(PyExc_RuntimeError, "Unable to open/read ui device");
     return nullptr;
 }
 
diff --git a/sources/pyside6/PySide6/glue/qtwidgets.cpp b/sources/pyside6/PySide6/glue/qtwidgets.cpp
index 1b3e94016..f886106cf 100644
--- a/sources/pyside6/PySide6/glue/qtwidgets.cpp
+++ b/sources/pyside6/PySide6/glue/qtwidgets.cpp
@@ -792,10 +792,8 @@ const char *styleOptionType(const QStyleOption *o)
 // @snippet qwizardpage-registerfield
 auto *signalInst = reinterpret_cast<PySideSignalInstance *>(%PYARG_4);
 const auto data = PySide::Signal::getEmitterData(signalInst);
-if (data.methodIndex == -1) {
-    PyErr_SetString(PyExc_RuntimeError, "QWizardPage::registerField(): Unable to retrieve signal emitter.");
-    return nullptr;
-}
+if (data.methodIndex == -1)
+    return PyErr_Format(PyExc_RuntimeError, "QWizardPage::registerField(): Unable to retrieve signal emitter.");
 const auto method = data.emitter->metaObject()->method(data.methodIndex);
 const QByteArray signature = QByteArrayLiteral("2") + method.methodSignature();
 %BEGIN_ALLOW_THREADS
diff --git a/sources/pyside6/libpyside/pysideclassinfo.cpp b/sources/pyside6/libpyside/pysideclassinfo.cpp
index 9ab5a7ad0..698cb1c76 100644
--- a/sources/pyside6/libpyside/pysideclassinfo.cpp
+++ b/sources/pyside6/libpyside/pysideclassinfo.cpp
@@ -51,16 +51,12 @@ PyObject *ClassInfoPrivate::tp_call(PyObject *self, PyObject *args, PyObject * /
 
     auto *pData = DecoratorPrivate::get<ClassInfoPrivate>(self);
 
-    if (pData->m_alreadyWrapped) {
-        PyErr_SetString(PyExc_TypeError, "This instance of ClassInfo() was already used to wrap an object");
-        return nullptr;
-    }
+    if (pData->m_alreadyWrapped)
+        return PyErr_Format(PyExc_TypeError, "This instance of ClassInfo() was already used to wrap an object");
 
     PyTypeObject *klassType = reinterpret_cast<PyTypeObject *>(klass);
-    if (!PySide::ClassInfo::setClassInfo(klassType, pData->m_data)) {
-        PyErr_SetString(PyExc_TypeError, "This decorator can only be used on classes that are subclasses of QObject");
-        return nullptr;
-    }
+    if (!PySide::ClassInfo::setClassInfo(klassType, pData->m_data))
+        return PyErr_Format(PyExc_TypeError, "This decorator can only be used on classes that are subclasses of QObject");
 
     pData->m_alreadyWrapped = true;
 
diff --git a/sources/pyside6/libpyside/pysidesignal.cpp b/sources/pyside6/libpyside/pysidesignal.cpp
index 774837e5b..d9dd14ad5 100644
--- a/sources/pyside6/libpyside/pysidesignal.cpp
+++ b/sources/pyside6/libpyside/pysidesignal.cpp
@@ -484,14 +484,10 @@ static PyObject *signalInstanceConnect(PyObject *self, PyObject *args, PyObject
         return nullptr;
 
     PySideSignalInstance *source = reinterpret_cast<PySideSignalInstance *>(self);
-    if (!source->d) {
-        PyErr_Format(PyExc_RuntimeError, "cannot connect uninitialized SignalInstance");
-        return nullptr;
-    }
-    if (source->deleted) {
-        PyErr_Format(PyExc_RuntimeError, "Signal source has been deleted");
-        return nullptr;
-    }
+    if (!source->d)
+        return PyErr_Format(PyExc_RuntimeError, "cannot connect uninitialized SignalInstance");
+    if (source->deleted)
+        return PyErr_Format(PyExc_RuntimeError, "Signal source has been deleted");
 
     Shiboken::AutoDecRef pyArgs(PyList_New(0));
 
@@ -564,10 +560,8 @@ static PyObject *signalInstanceConnect(PyObject *self, PyObject *args, PyObject
         Shiboken::AutoDecRef tupleArgs(PyList_AsTuple(pyArgs));
         Shiboken::AutoDecRef pyMethod(PyObject_GetAttr(source->d->source,
                                                        PySide::PySideName::qtConnect()));
-        if (pyMethod.isNull()) { // PYSIDE-79: check if pyMethod exists.
-            PyErr_SetString(PyExc_RuntimeError, "method 'connect' vanished!");
-            return nullptr;
-        }
+        if (pyMethod.isNull())  // PYSIDE-79: check if pyMethod exists.
+            return PyErr_Format(PyExc_RuntimeError, "method 'connect' vanished!");
         PyObject *result = PyObject_CallObject(pyMethod, tupleArgs);
         if (connection_Check(result))
             return result;
@@ -587,17 +581,13 @@ static int argCountInSignature(const char *signature)
 static PyObject *signalInstanceEmit(PyObject *self, PyObject *args)
 {
     PySideSignalInstance *source = reinterpret_cast<PySideSignalInstance *>(self);
-    if (!source->d) {
-        PyErr_Format(PyExc_RuntimeError, "cannot emit uninitialized SignalInstance");
-        return nullptr;
-    }
+    if (!source->d)
+        return PyErr_Format(PyExc_RuntimeError, "cannot emit uninitialized SignalInstance");
 
     // PYSIDE-2201: Check if the object has vanished meanwhile.
     //              Tried to revive it without exception, but this gives problems.
-    if (source->deleted) {
-        PyErr_Format(PyExc_RuntimeError, "The SignalInstance object was already deleted");
-        return nullptr;
-    }
+    if (source->deleted)
+        return PyErr_Format(PyExc_RuntimeError, "The SignalInstance object was already deleted");
 
     Shiboken::AutoDecRef pyArgs(PyList_New(0));
     int numArgsGiven = PySequence_Fast_GET_SIZE(args);
@@ -657,8 +647,7 @@ static PyObject *signalInstanceGetItem(PyObject *self, PyObject *key)
         message += '"' + data->d->signature + '"';
     }
 
-    PyErr_SetString(PyExc_IndexError, message.constData());
-    return nullptr;
+    return PyErr_Format(PyExc_IndexError, message.constData());
 }
 
 static inline void warnDisconnectFailed(PyObject *aSlot, const QByteArray &signature)
@@ -675,10 +664,9 @@ static inline void warnDisconnectFailed(PyObject *aSlot, const QByteArray &signa
 static PyObject *signalInstanceDisconnect(PyObject *self, PyObject *args)
 {
     auto source = reinterpret_cast<PySideSignalInstance *>(self);
-    if (!source->d) {
-        PyErr_Format(PyExc_RuntimeError, "cannot disconnect uninitialized SignalInstance");
-        return nullptr;
-    }
+    if (!source->d)
+        return PyErr_Format(PyExc_RuntimeError, "cannot disconnect uninitialized SignalInstance");
+
     Shiboken::AutoDecRef pyArgs(PyList_New(0));
 
     PyObject *slot = Py_None;
@@ -761,10 +749,8 @@ static PyObject *signalCall(PyObject *self, PyObject *args, PyObject *kw)
     // The only way calling a signal can succeed (the Python equivalent of C++'s operator() )
     // is when a method with the same name as the signal is attached to an object.
     // An example is QProcess::error() (don't check the docs, but the source code of qprocess.h).
-    if (!signal->homonymousMethod) {
-        PyErr_SetString(PyExc_TypeError, "native Qt signal is not callable");
-        return nullptr;
-    }
+    if (!signal->homonymousMethod)
+        return PyErr_Format(PyExc_TypeError, "native Qt signal is not callable");
 
     // Check if there exists a method with the same name as the signal, which is also a static
     // method in C++ land.
diff --git a/sources/pyside6/libpysideqml/pysideqmlregistertype.cpp b/sources/pyside6/libpysideqml/pysideqmlregistertype.cpp
index 223c6eaa3..4ccd459d5 100644
--- a/sources/pyside6/libpysideqml/pysideqmlregistertype.cpp
+++ b/sources/pyside6/libpysideqml/pysideqmlregistertype.cpp
@@ -392,7 +392,7 @@ QObject *SingletonQObjectCreationBase::handleReturnValue(PyObject *retVal)
     using Shiboken::Conversions::isPythonToCppPointerConvertible;
     // Make sure the callback returns something we can convert, else the entire application will crash.
     if (retVal == nullptr) {
-        PyErr_SetString(PyExc_TypeError, "Callback returns 0 value.");
+        PyErr_Format(PyExc_TypeError, "Callback returns 0 value.");
         return nullptr;
     }
     if (isPythonToCppPointerConvertible(qObjectType(), retVal) == nullptr) {
diff --git a/sources/shiboken6/libshiboken/sbkcontainer.h b/sources/shiboken6/libshiboken/sbkcontainer.h
index 240c772a9..8ad5aadc6 100644
--- a/sources/shiboken6/libshiboken/sbkcontainer.h
+++ b/sources/shiboken6/libshiboken/sbkcontainer.h
@@ -74,10 +74,9 @@ public:
 
     static PyObject *tpNewInvalid(PyTypeObject * /* subtype */, PyObject * /* args */, PyObject * /* kwds */)
     {
-        PyErr_Format(PyExc_NotImplementedError,
+        return PyErr_Format(PyExc_NotImplementedError,
                      "Opaque containers of type '%s' cannot be instantiated.",
                      typeid(SequenceContainer).name());
-        return nullptr;
     }
 
     static int tpInit(PyObject * /* self */, PyObject * /* args */, PyObject * /* kwds */)
@@ -105,10 +104,8 @@ public:
     static PyObject *sqGetItem(PyObject *self, Py_ssize_t i)
     {
         auto *d = get(self);
-        if (i < 0 || i >= Py_ssize_t(d->m_list->size())) {
-            PyErr_SetString(PyExc_IndexError, "index out of bounds");
-            return nullptr;
-        }
+        if (i < 0 || i >= Py_ssize_t(d->m_list->size()))
+            return PyErr_Format(PyExc_IndexError, "index out of bounds");
         auto it = std::cbegin(*d->m_list);
         std::advance(it, i);
         return ShibokenContainerValueConverter<value_type>::convertValueToPython(*it);
@@ -133,14 +130,10 @@ public:
     static PyObject *push_back(PyObject *self, PyObject *pyArg)
     {
         auto *d = get(self);
-        if (!ShibokenContainerValueConverter<value_type>::checkValue(pyArg)) {
-            PyErr_SetString(PyExc_TypeError, "wrong type passed to append.");
-            return nullptr;
-        }
-        if (d->m_const) {
-            PyErr_SetString(PyExc_TypeError, msgModifyConstContainer);
-            return nullptr;
-        }
+        if (!ShibokenContainerValueConverter<value_type>::checkValue(pyArg))
+            return PyErr_Format(PyExc_TypeError, "wrong type passed to append.");
+        if (d->m_const)
+            return PyErr_Format(PyExc_TypeError, msgModifyConstContainer);
 
         OptionalValue value = ShibokenContainerValueConverter<value_type>::convertValueToCpp(pyArg);
         if (!value.has_value())
@@ -152,14 +145,10 @@ public:
     static PyObject *push_front(PyObject *self, PyObject *pyArg)
     {
         auto *d = get(self);
-        if (!ShibokenContainerValueConverter<value_type>::checkValue(pyArg)) {
-            PyErr_SetString(PyExc_TypeError, "wrong type passed to append.");
-            return nullptr;
-        }
-        if (d->m_const) {
-            PyErr_SetString(PyExc_TypeError, msgModifyConstContainer);
-            return nullptr;
-        }
+        if (!ShibokenContainerValueConverter<value_type>::checkValue(pyArg))
+            return PyErr_Format(PyExc_TypeError, "wrong type passed to append.");
+        if (d->m_const)
+            return PyErr_Format(PyExc_TypeError, msgModifyConstContainer);
 
         OptionalValue value = ShibokenContainerValueConverter<value_type>::convertValueToCpp(pyArg);
         if (!value.has_value())
@@ -171,10 +160,8 @@ public:
     static PyObject *clear(PyObject *self)
     {
         auto *d = get(self);
-        if (d->m_const) {
-            PyErr_SetString(PyExc_TypeError, msgModifyConstContainer);
-            return nullptr;
-        }
+        if (d->m_const)
+            return PyErr_Format(PyExc_TypeError, msgModifyConstContainer);
 
         d->m_list->clear();
         Py_RETURN_NONE;
@@ -183,10 +170,8 @@ public:
     static PyObject *pop_back(PyObject *self)
     {
         auto *d = get(self);
-        if (d->m_const) {
-            PyErr_SetString(PyExc_TypeError, msgModifyConstContainer);
-            return nullptr;
-        }
+        if (d->m_const)
+            return PyErr_Format(PyExc_TypeError, msgModifyConstContainer);
 
         d->m_list->pop_back();
         Py_RETURN_NONE;
@@ -195,10 +180,8 @@ public:
     static PyObject *pop_front(PyObject *self)
     {
         auto *d = get(self);
-        if (d->m_const) {
-            PyErr_SetString(PyExc_TypeError, msgModifyConstContainer);
-            return nullptr;
-        }
+        if (d->m_const)
+            return PyErr_Format(PyExc_TypeError, msgModifyConstContainer);
 
         d->m_list->pop_front();
         Py_RETURN_NONE;
@@ -208,21 +191,16 @@ public:
     static PyObject *reserve(PyObject *self, PyObject *pyArg)
     {
         auto *d = get(self);
-        if (PyLong_Check(pyArg) == 0) {
-            PyErr_SetString(PyExc_TypeError, "wrong type passed to reserve().");
-            return nullptr;
-        }
-        if (d->m_const) {
-            PyErr_SetString(PyExc_TypeError, msgModifyConstContainer);
-            return nullptr;
-        }
+        if (PyLong_Check(pyArg) == 0)
+            return PyErr_Format(PyExc_TypeError, "wrong type passed to reserve().");
+        if (d->m_const)
+            return PyErr_Format(PyExc_TypeError, msgModifyConstContainer);
 
         if constexpr (ShibokenContainerHasReserve<SequenceContainer>::value) {
             const Py_ssize_t size = PyLong_AsSsize_t(pyArg);
             d->m_list->reserve(size);
         } else {
-            PyErr_SetString(PyExc_TypeError, "Container does not support reserve().");
-            return nullptr;
+            return PyErr_Format(PyExc_TypeError, "Container does not support reserve().");
         }
 
         Py_RETURN_NONE;
diff --git a/sources/shiboken6/libshiboken/voidptr.cpp b/sources/shiboken6/libshiboken/voidptr.cpp
index 7045b08b1..8bb3f6ac8 100644
--- a/sources/shiboken6/libshiboken/voidptr.cpp
+++ b/sources/shiboken6/libshiboken/voidptr.cpp
@@ -156,10 +156,9 @@ PyObject *SbkVoidPtrObject_int(PyObject *v)
 PyObject *toBytes(PyObject *self, PyObject * /* args */)
 {
     auto *sbkObject = reinterpret_cast<SbkVoidPtrObject *>(self);
-    if (sbkObject->size < 0) {
-        PyErr_SetString(PyExc_IndexError, "VoidPtr does not have a size set.");
-        return nullptr;
-    }
+    if (sbkObject->size < 0)
+        return PyErr_Format(PyExc_IndexError, "VoidPtr does not have a size set.");
+
     PyObject *bytes = PyBytes_FromStringAndSize(reinterpret_cast<const char *>(sbkObject->cptr),
                                                 sbkObject->size);
     Py_XINCREF(bytes);