App: modernize C++: return braced init list

src/App/Application.cpp

@@ -593,7 +593,7 @@ std::vector<App::Document*> Application::getDocuments() const
 std::string Application::getUniqueDocumentName(const char *Name, bool tempDoc) const
 {
     if (!Name || *Name == '\0')
-        return std::string();
+        return {};
     std::string CleanName = Base::Tools::getIdentifier(Name);
 
     // name in use?
@@ -3160,7 +3160,7 @@ std::tuple<QString, QString, QString> getCustomPaths()
         userTemp = fi.absoluteFilePath();
     }
 
-    return std::tuple<QString, QString, QString>(userHome, userData, userTemp);
+    return {userHome, userData, userTemp};
 }
 
 /*!

src/App/ComplexGeoDataPyImp.cpp

@@ -43,7 +43,7 @@ using namespace Base;
 // returns a string which represent the object e.g. when printed in python
 std::string ComplexGeoDataPy::representation() const
 {
-    return std::string("<ComplexGeoData object>");
+    return {"<ComplexGeoData object>"};
 }
 
 PyObject* ComplexGeoDataPy::getElementTypes(PyObject *args)

src/App/Document.cpp

@@ -3799,7 +3799,7 @@ const char * Document::getObjectName(DocumentObject *pFeat) const
 std::string Document::getUniqueObjectName(const char *Name) const
 {
     if (!Name || *Name == '\0')
-        return std::string();
+        return {};
     std::string CleanName = Base::Tools::getIdentifier(Name);
 
     // name in use?

src/App/DocumentObject.cpp

@@ -312,7 +312,7 @@ int DocumentObject::isExporting() const {
 
 std::string DocumentObject::getExportName(bool forced) const {
     if(!pcNameInDocument)
-        return std::string();
+        return {};
 
     if(!forced && !isExporting())
         return *pcNameInDocument;

src/App/DocumentObjectExtensionPyImp.cpp

@@ -32,7 +32,7 @@ using namespace App;
 // returns a string which represent the object e.g. when printed in python
 std::string DocumentObjectExtensionPy::representation() const
 {
-    return std::string("<document object extension>");
+    return {"<document object extension>"};
 }
 
 PyObject *DocumentObjectExtensionPy::getCustomAttributes(const char* /*attr*/) const

src/App/DocumentObjectGroupPyImp.cpp

@@ -34,7 +34,7 @@ using namespace App;
 // returns a string which represent the object e.g. when printed in python
 std::string DocumentObjectGroupPy::representation() const
 {
-    return std::string("<group object>");
+    return {"<group object>"};
 }
 
 PyObject *DocumentObjectGroupPy::getCustomAttributes(const char* /*attr*/) const

src/App/DocumentObjectPyImp.cpp

@@ -55,12 +55,12 @@ Py::String DocumentObjectPy::getName() const
     if (!internal) {
         throw Py::RuntimeError(std::string("This object is currently not part of a document"));
     }
-    return Py::String(std::string(internal));
+    return {std::string(internal)};
 }
 
 Py::String DocumentObjectPy::getFullName() const
 {
-    return Py::String(getDocumentObjectPtr()->getFullName());
+    return {getDocumentObjectPtr()->getFullName()};
 }
 
 Py::Object DocumentObjectPy::getDocument() const
@@ -694,7 +694,7 @@ PyObject*  DocumentObjectPy::getParent(PyObject *args)
 Py::Boolean DocumentObjectPy::getMustExecute() const
 {
     try {
-        return Py::Boolean(getDocumentObjectPtr()->mustExecute()?true:false);
+        return {getDocumentObjectPtr()->mustExecute() ? true : false};
     }
     catch (const Base::Exception& e) {
         throw Py::RuntimeError(e.what());
@@ -741,7 +741,7 @@ Py::Int DocumentObjectPy::getID() const {
 }
 
 Py::Boolean DocumentObjectPy::getRemoving() const {
-    return Py::Boolean(getDocumentObjectPtr()->testStatus(ObjectStatus::Remove));
+    return {getDocumentObjectPtr()->testStatus(ObjectStatus::Remove)};
 }
 
 PyObject *DocumentObjectPy::resolve(PyObject *args)
@@ -813,11 +813,11 @@ PyObject *DocumentObjectPy::adjustRelativeLinks(PyObject *args) {
 }
 
 Py::String DocumentObjectPy::getOldLabel() const {
-    return Py::String(getDocumentObjectPtr()->getOldLabel());
+    return {getDocumentObjectPtr()->getOldLabel()};
 }
 
 Py::Boolean DocumentObjectPy::getNoTouch() const {
-    return Py::Boolean(getDocumentObjectPtr()->testStatus(ObjectStatus::NoTouch));
+    return {getDocumentObjectPtr()->testStatus(ObjectStatus::NoTouch)};
 }
 
 void DocumentObjectPy::setNoTouch(Py::Boolean value) {

src/App/DocumentObserver.cpp

@@ -364,7 +364,7 @@ std::string SubObjectT::getNewElementName() const {
     std::pair<std::string, std::string> element;
     auto obj = getObject();
     if(!obj)
-        return std::string();
+        return {};
     GeoFeature::resolveElement(obj,subname.c_str(),element);
     return std::move(element.first);
 }
@@ -373,7 +373,7 @@ std::string SubObjectT::getOldElementName(int *index) const {
     std::pair<std::string, std::string> element;
     auto obj = getObject();
     if(!obj)
-        return std::string();
+        return {};
     GeoFeature::resolveElement(obj,subname.c_str(),element);
     if(!index)
         return std::move(element.second);

src/App/DocumentPyImp.cpp

@@ -472,7 +472,7 @@ PyObject*  DocumentPy::commitTransaction(PyObject * args)
 }
 
 Py::Boolean DocumentPy::getHasPendingTransaction() const {
-    return Py::Boolean(getDocumentPtr()->hasPendingTransaction());
+    return {getDocumentPtr()->hasPendingTransaction()};
 }
 
 PyObject*  DocumentPy::undo(PyObject * args)
@@ -780,17 +780,17 @@ Py::String  DocumentPy::getDependencyGraph() const
 {
     std::stringstream out;
     getDocumentPtr()->exportGraphviz(out);
-    return Py::String(out.str());
+    return {out.str()};
 }
 
 Py::String DocumentPy::getName() const
 {
-    return Py::String(getDocumentPtr()->getName());
+    return {getDocumentPtr()->getName()};
 }
 
 Py::Boolean DocumentPy::getRecomputesFrozen() const
 {
-    return Py::Boolean(getDocumentPtr()->testStatus(Document::Status::SkipRecompute));
+    return {getDocumentPtr()->testStatus(Document::Status::SkipRecompute)};
 }
 
 void DocumentPy::setRecomputesFrozen(Py::Boolean arg)
@@ -942,35 +942,35 @@ PyObject *DocumentPy::getDependentDocuments(PyObject *args) {
 
 Py::Boolean DocumentPy::getRestoring() const
 {
-    return Py::Boolean(getDocumentPtr()->testStatus(Document::Status::Restoring));
+    return {getDocumentPtr()->testStatus(Document::Status::Restoring)};
 }
 
 Py::Boolean DocumentPy::getPartial() const
 {
-    return Py::Boolean(getDocumentPtr()->testStatus(Document::Status::PartialDoc));
+    return {getDocumentPtr()->testStatus(Document::Status::PartialDoc)};
 }
 
 Py::Boolean DocumentPy::getImporting() const
 {
-    return Py::Boolean(getDocumentPtr()->testStatus(Document::Status::Importing));
+    return {getDocumentPtr()->testStatus(Document::Status::Importing)};
 }
 
 Py::Boolean DocumentPy::getRecomputing() const
 {
-    return Py::Boolean(getDocumentPtr()->testStatus(Document::Status::Recomputing));
+    return {getDocumentPtr()->testStatus(Document::Status::Recomputing)};
 }
 
 Py::Boolean DocumentPy::getTransacting() const
 {
-    return Py::Boolean(getDocumentPtr()->isPerformingTransaction());
+    return {getDocumentPtr()->isPerformingTransaction()};
 }
 
 Py::String DocumentPy::getOldLabel() const
 {
-    return Py::String(getDocumentPtr()->getOldLabel());
+    return {getDocumentPtr()->getOldLabel()};
 }
 
 Py::Boolean DocumentPy::getTemporary() const
 {
-    return Py::Boolean(getDocumentPtr()->testStatus(Document::TempDoc));
+    return {getDocumentPtr()->testStatus(Document::TempDoc)};
 }

src/App/DynamicProperty.cpp

@@ -328,7 +328,7 @@ DynamicProperty::PropData DynamicProperty::getDynamicPropertyData(const Property
     auto it = index.find(const_cast<Property*>(prop));
     if(it != index.end())
         return *it;
-    return PropData();
+    return {};
 }
 
 bool DynamicProperty::changeDynamicProperty(const Property *prop, const char *group, const char *doc) {

src/App/ElementMap.cpp

@@ -848,12 +848,12 @@ IndexedName ElementMap::find(const MappedName& name, ElementIDRefs* sids) const
 MappedName ElementMap::find(const IndexedName& idx, ElementIDRefs* sids) const
 {
     if (!idx) {
-        return MappedName();
+        return {};
     }
 
     auto iter = this->indexedNames.find(idx.getType());
     if (iter == this->indexedNames.end()) {
-        return MappedName();
+        return {};
     }
 
     auto& indices = iter->second;

src/App/ElementNamingUtils.cpp

@@ -12,7 +12,7 @@ const char *Data::isMappedElement(const char *name) {
 
 std::string Data::newElementName(const char *name) {
     if(!name)
-        return std::string();
+        return {};
     const char *dot = strrchr(name,'.');
     if(!dot || dot==name)
         return name;
@@ -30,7 +30,7 @@ std::string Data::newElementName(const char *name) {
 
 std::string Data::oldElementName(const char *name) {
     if(!name)
-        return std::string();
+        return {};
     const char *dot = strrchr(name,'.');
     if(!dot || dot==name)
         return name;
@@ -48,7 +48,7 @@ std::string Data::oldElementName(const char *name) {
 
 std::string Data::noElementName(const char *name) {
     if(!name)
-        return std::string();
+        return {};
     auto element = findElementName(name);
     if(element)
         return std::string(name,element-name);

src/App/Expression.cpp

@@ -449,12 +449,12 @@ Py::Object pyObjectFromAny(const App::any &value) {
 App::any pyObjectToAny(Py::Object value, bool check) {
 
     if(value.isNone())
-        return App::any();
+        return {};
 
     PyObject *pyvalue = value.ptr();
 
     if(!check)
-        return App::any(pyObjectWrap(pyvalue));
+        return {pyObjectWrap(pyvalue)};
 
     if (PyObject_TypeCheck(pyvalue, &Base::QuantityPy::Type)) {
         Base::QuantityPy * qp = static_cast<Base::QuantityPy*>(pyvalue);
@@ -1048,7 +1048,7 @@ ExpressionPtr Expression::updateLabelReference(
         App::DocumentObject *obj, const std::string &ref, const char *newLabel) const
 {
     if(ref.size()<=2)
-        return ExpressionPtr();
+        return {};
     std::vector<std::string> labels;
     for(auto &v : getIdentifiers())
         v.first.getDepLabels(labels);
@@ -1061,7 +1061,7 @@ ExpressionPtr Expression::updateLabelReference(
             return ExpressionPtr(expr);
         }
     }
-    return ExpressionPtr();
+    return {};
 }
 
 class ReplaceObjectExpressionVisitor : public ExpressionVisitor {
@@ -1097,7 +1097,7 @@ ExpressionPtr Expression::replaceObject(const DocumentObject *parent,
     const_cast<Expression*>(this)->visit(v);
 
     if(v.paths.empty())
-        return ExpressionPtr();
+        return {};
 
     // Now make a copy and do the actual replacement
     auto expr = copy();

src/App/ExpressionTokenizer.cpp

@@ -67,7 +67,7 @@ QString ExpressionTokenizer::perform(const QString& prefix, int pos)
 
     // No tokens
     if (tokens.empty()) {
-        return QString();
+        return {};
     }
 
     prefixEnd = prefix.size();
@@ -114,7 +114,7 @@ QString ExpressionTokenizer::perform(const QString& prefix, int pos)
     if (!stringing && !prefix.isEmpty() &&
             prefixEnd > 0 && prefixEnd <= prefix.size() &&
             prefix[prefixEnd-1] == QChar(32)) {
-        return QString();
+        return {};
     }
 
     if (!stringing) {

src/App/Extension.cpp

@@ -115,12 +115,9 @@ std::string Extension::name() const {
 
     if (pos != std::string::npos)
         return temp.substr(pos+1);
-    else
-        return std::string();
+    return {};
 }
 
-
-
 Property* Extension::extensionGetPropertyByName(const char* name) const {
 
     return extensionGetPropertyData().getPropertyByName(this, name);

src/App/ExtensionContainerPyImp.cpp

@@ -38,7 +38,7 @@ using namespace App;
 // returns a string which represent the object e.g. when printed in python
 std::string ExtensionContainerPy::representation() const
 {
-    return std::string("<extension>");
+    return {"<extension>"};
 }
 
 int  ExtensionContainerPy::initialization() {

src/App/ExtensionPyImp.cpp

@@ -34,7 +34,7 @@ using namespace App;
 // returns a string which represent the object e.g. when printed in python
 std::string ExtensionPy::representation() const
 {
-    return std::string("<extension>");
+    return {"<extension>"};
 }
 
 PyObject *ExtensionPy::getCustomAttributes(const char* /*attr*/) const

src/App/FeaturePython.cpp

@@ -480,7 +480,7 @@ std::string FeaturePythonImp::getViewProviderName()
         e.ReportException();
     }
 
-    return std::string();
+    return {};
 }
 
 FeaturePythonImp::ValueT

src/App/GeoFeatureGroupExtension.cpp

@@ -235,7 +235,7 @@ void GeoFeatureGroupExtension::extensionOnChanged(const Property* p) {
 std::vector< DocumentObject* > GeoFeatureGroupExtension::getScopedObjectsFromLinks(const DocumentObject* obj, LinkScope scope) {
 
     if(!obj)
-        return std::vector< DocumentObject* >();
+        return {};
 
     //we get all linked objects. We can't use outList() as this includes the links from expressions
     std::vector< App::DocumentObject* > result;
@@ -256,7 +256,7 @@ std::vector< DocumentObject* > GeoFeatureGroupExtension::getScopedObjectsFromLin
 std::vector< DocumentObject* > GeoFeatureGroupExtension::getScopedObjectsFromLink(App::Property* prop, LinkScope scope) {
 
     if(!prop)
-        return std::vector< DocumentObject* >();
+        return {};
 
     std::vector< App::DocumentObject* > result;
     auto link = Base::freecad_dynamic_cast<PropertyLinkBase>(prop);
@@ -321,7 +321,7 @@ void GeoFeatureGroupExtension::getCSInList(const DocumentObject* obj,
 std::vector< DocumentObject* > GeoFeatureGroupExtension::getCSRelevantLinks(const DocumentObject* obj) {
 
     if(!obj)
-        return std::vector< DocumentObject* >();
+        return {};
 
     //get all out links
     std::vector<DocumentObject*> vec;

src/App/GeoFeatureGroupExtensionPyImp.cpp

@@ -33,10 +33,9 @@ using namespace App;
 // returns a string which represents the object e.g. when printed in python
 std::string GeoFeatureGroupExtensionPy::representation() const
 {
-    return std::string("<GeoFeatureGroup object>");
+    return {"<GeoFeatureGroup object>"};
 }
 
-
 PyObject *GeoFeatureGroupExtensionPy::getCustomAttributes(const char* /*attr*/) const
 {
     return nullptr;

src/App/GeoFeaturePyImp.cpp

@@ -34,7 +34,7 @@ using namespace App;
 // returns a string which represents the object e.g. when printed in python
 std::string GeoFeaturePy::representation() const
 {
-    return std::string("<GeoFeature object>");
+    return {"<GeoFeature object>"};
 }
 
 PyObject* GeoFeaturePy::getPaths(PyObject * /*args*/)

src/App/Graphviz.cpp

@@ -132,7 +132,7 @@ void Document::exportGraphviz(std::ostream& out) const
         std::string getId(const ObjectIdentifier & path) {
             DocumentObject * docObj = path.getDocumentObject();
             if (!docObj)
-                return std::string();
+                return {};
 
             return std::string((docObj)->getDocument()->getName()) + "#" + docObj->getNameInDocument() + "." + path.getPropertyName() + path.getSubPathStr();
         }

src/App/GroupExtensionPyImp.cpp

@@ -36,7 +36,7 @@ using namespace App;
 // returns a string which represent the object e.g. when printed in python
 std::string GroupExtensionPy::representation() const
 {
-    return std::string("<group extension object>");
+    return {"<group extension object>"};
 }
 
 PyObject*  GroupExtensionPy::newObject(PyObject *args)

src/App/MaterialPyImp.cpp

@@ -80,7 +80,7 @@ int MaterialPy::PyInit(PyObject* args, PyObject* kwds)
 // returns a string which represents the object e.g. when printed in python
 std::string MaterialPy::representation() const
 {
-    return std::string("<Material object>");
+    return {"<Material object>"};
 }
 
 PyObject* MaterialPy::set(PyObject * args)

src/App/ObjectIdentifier.cpp

@@ -374,13 +374,13 @@ const std::string &ObjectIdentifier::toString() const
 std::string ObjectIdentifier::toPersistentString() const {
 
     if(!owner)
-        return std::string();
+        return {};
 
     std::ostringstream s;
     ResolveResults result(*this);
 
     if(result.propertyIndex >= (int)components.size())
-        return std::string();
+        return {};
 
     if(localProperty ||
        (result.resolvedProperty &&
@@ -1776,7 +1776,7 @@ App::any ObjectIdentifier::getValue(bool pathValue, bool *isPseudoProperty) cons
     }catch(Py::Exception &) {
         Base::PyException::ThrowException();
     }
-    return App::any();
+    return {};
 }
 
 Py::Object ObjectIdentifier::getPyValue(bool pathValue, bool *isPseudoProperty) const

src/App/OriginGroupExtensionPyImp.cpp

@@ -32,7 +32,7 @@ using namespace App;
 // returns a string which represents the object e.g. when printed in python
 std::string OriginGroupExtensionPy::representation() const
 {
-    return std::string("<OriginGroup object>");
+    return {"<OriginGroup object>"};
 }
 
 PyObject *OriginGroupExtensionPy::getCustomAttributes(const char* /*attr*/) const

src/App/PartPyImp.cpp

@@ -32,7 +32,7 @@ using namespace App;
 // returns a string which represents the object e.g. when printed in python
 std::string PartPy::representation() const
 {
-    return std::string("<Part object>");
+    return {"<Part object>"};
 }
 
 PyObject *PartPy::getCustomAttributes(const char* /*attr*/) const

src/App/PropertyContainer.h

@@ -158,7 +158,7 @@ public:
 
   unsigned int getMemSize () const override;
 
-  virtual std::string getFullName() const {return std::string();}
+  virtual std::string getFullName() const {return {};}
 
   /// find a property by its name
   virtual Property *getPropertyByName(const char* name) const;

src/App/PropertyContainerPyImp.cpp

@@ -45,7 +45,7 @@ using namespace App;
 // returns a string which represent the object e.g. when printed in python
 std::string PropertyContainerPy::representation() const
 {
-    return std::string("<property container>");
+    return {"<property container>"};
 }
 
 PyObject*  PropertyContainerPy::getPropertyByName(PyObject *args)

src/App/PropertyExpressionEngine.cpp

@@ -811,7 +811,7 @@ std::string PropertyExpressionEngine::validateExpression(const ObjectIdentifier
         return e.what();
     }
 
-    return std::string();
+    return {};
 }
 
 /**

src/App/PropertyGeo.h

@@ -102,7 +102,7 @@ public:
     bool getPyPathValue(const ObjectIdentifier &path, Py::Object &res) const override;
 
     virtual Base::Unit getUnit() const {
-        return Base::Unit();
+        return {};
     }
 
     bool isSame(const Property &other) const override {

src/App/PropertyLinks.cpp

@@ -147,7 +147,7 @@ std::string PropertyLinkBase::updateLabelReference(const App::DocumentObject *pa
         const char *subname, App::DocumentObject *obj, const std::string &ref, const char *newLabel)
 {
     if(!obj || !obj->getNameInDocument() || !parent || !parent->getNameInDocument())
-        return std::string();
+        return {};
 
     // Because the label is allowed to be the same across different
     // hierarchies, we have to search for all occurrences, and make sure the
@@ -162,7 +162,7 @@ std::string PropertyLinkBase::updateLabelReference(const App::DocumentObject *pa
             return sub;
         }
     }
-    return std::string();
+    return {};
 }
 
 std::vector<std::pair<Property*, std::unique_ptr<Property> > >
@@ -192,7 +192,7 @@ PropertyLinkBase::updateLabelReferences(App::DocumentObject *obj, const char *ne
 
 static std::string propertyName(const Property *prop) {
     if(!prop)
-        return std::string();
+        return {};
     if(!prop->getContainer() || !prop->hasName()) {
         auto xlink = Base::freecad_dynamic_cast<const PropertyXLink>(prop);
         if(xlink)
@@ -1238,7 +1238,7 @@ std::string PropertyLinkBase::tryImportSubName(const App::DocumentObject *obj, c
         const App::Document *doc, const std::map<std::string,std::string> &nameMap)
 {
     if(!doc || !obj || !obj->getNameInDocument())
-        return std::string();
+        return {};
 
     std::ostringstream ss;
     std::string subname(_subname);
@@ -1249,7 +1249,7 @@ std::string PropertyLinkBase::tryImportSubName(const App::DocumentObject *obj, c
         auto sobj = obj->getSubObject(subname.c_str());
         if(!sobj) {
             FC_ERR("Failed to restore label reference " << obj->getFullName() << '.' << subname);
-            return std::string();
+            return {};
         }
         dot[0] = 0;
         if(next[0] == '$') {
@@ -1273,7 +1273,7 @@ std::string PropertyLinkBase::tryImportSubName(const App::DocumentObject *obj, c
     }
     if(sub!=subname.c_str())
         return ss.str();
-    return std::string();
+    return {};
 }
 
 #define ATTR_SHADOWED "shadowed"

src/App/StringHasherPyImp.cpp

@@ -127,7 +127,7 @@ Py::Long StringHasherPy::getSize() const
 
 Py::Boolean StringHasherPy::getSaveAll() const
 {
-    return Py::Boolean(getStringHasherPtr()->getSaveAll());
+    return {getStringHasherPtr()->getSaveAll()};
 }
 
 void StringHasherPy::setSaveAll(Py::Boolean value)

src/App/StringIDPyImp.cpp

@@ -66,17 +66,17 @@ Py::List StringIDPy::getRelated() const
 
 Py::String StringIDPy::getData() const
 {
-    return Py::String(getStringIDPtr()->dataToText(this->_index));
+    return {getStringIDPtr()->dataToText(this->_index)};
 }
 
 Py::Boolean StringIDPy::getIsBinary() const
 {
-    return Py::Boolean(getStringIDPtr()->isBinary());
+    return {getStringIDPtr()->isBinary()};
 }
 
 Py::Boolean StringIDPy::getIsHashed() const
 {
-    return Py::Boolean(getStringIDPtr()->isHashed());
+    return {getStringIDPtr()->isHashed()};
 }
 
 Py::Long StringIDPy::getIndex() const