From 39807035dde25c5db453ee46df7b95e6ac53b575 Mon Sep 17 00:00:00 2001
From: Marco Bubke <marco.bubke@qt.io>
Date: Sun, 27 Apr 2025 09:14:09 +0200
Subject: [PATCH] QmlDesigner: Optimize method by using constinit QString for
 null return value

- Introduced constinit QString null to replace temporary QString object.
- Updated return type to const QString& for better performance and
consistency.
- Ensured method returns null when no valid binding property is found.

Change-Id: Ib74d45237d9396cca72d15bd550b6fb376da84cd
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
---
 .../qmldesigner/libs/designercore/include/bindingproperty.h | 2 +-
 .../qmldesigner/libs/designercore/model/bindingproperty.cpp | 6 ++++--
 .../libs/designercore/model/internalbindingproperty.cpp     | 2 +-
 .../libs/designercore/model/internalbindingproperty.h       | 2 +-
 4 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/plugins/qmldesigner/libs/designercore/include/bindingproperty.h b/src/plugins/qmldesigner/libs/designercore/include/bindingproperty.h
index 97eabc040e8..f33ebb6af8d 100644
--- a/src/plugins/qmldesigner/libs/designercore/include/bindingproperty.h
+++ b/src/plugins/qmldesigner/libs/designercore/include/bindingproperty.h
@@ -16,7 +16,7 @@ class QMLDESIGNERCORE_EXPORT BindingProperty final : public QmlDesigner::Abstrac
 
 public:
     void setExpression(const QString &expression);
-    QString expression() const;
+    const QString &expression() const;
 
     BindingProperty();
     BindingProperty(const BindingProperty &property, AbstractView *view);
diff --git a/src/plugins/qmldesigner/libs/designercore/model/bindingproperty.cpp b/src/plugins/qmldesigner/libs/designercore/model/bindingproperty.cpp
index 57778d30bd1..ec073baab6f 100644
--- a/src/plugins/qmldesigner/libs/designercore/model/bindingproperty.cpp
+++ b/src/plugins/qmldesigner/libs/designercore/model/bindingproperty.cpp
@@ -56,14 +56,16 @@ void BindingProperty::setExpression(const QString &expression)
     privateModel()->setBindingProperty(internalNodeSharedPointer(), name(), expression);
 }
 
-QString BindingProperty::expression() const
+const constinit QString null;
+
+const QString &BindingProperty::expression() const
 {
     if (isValid()) {
         if (auto property = internalNode()->bindingProperty(name()))
             return property->expression();
     }
 
-    return QString();
+    return null;
 }
 
 ModelNode BindingProperty::resolveBinding(const QString &binding, ModelNode currentNode) const
diff --git a/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.cpp b/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.cpp
index 44b2dce30ec..be16a01e3dd 100644
--- a/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.cpp
+++ b/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.cpp
@@ -17,7 +17,7 @@ bool InternalBindingProperty::isValid() const
     return InternalProperty::isValid() && isBindingProperty();
 }
 
-QString InternalBindingProperty::expression() const
+const QString &InternalBindingProperty::expression() const
 {
     return m_expression;
 }
diff --git a/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.h b/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.h
index 6744a814925..d3c7d86cbe9 100644
--- a/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.h
+++ b/src/plugins/qmldesigner/libs/designercore/model/internalbindingproperty.h
@@ -18,7 +18,7 @@ public:
 
     bool isValid() const override;
 
-    QString expression() const;
+    const QString &expression() const;
     void setExpression(const QString &expression);
 
     void setDynamicExpression(const TypeName &type, const QString &expression);