Introduce method to query KConfigSkeletonItem default value

5.64 added an isDefault method however this doesn't suffice for usage in
KConfigDialogManager which compares a current value to the default.
KConfigDialogManager currently uses a hack with side effects.

Exposing the value directly solves that.

3 files changed, 27 insertions, 0 deletions

diff --git a/src/core/kcoreconfigskeleton.cpp b/src/core/kcoreconfigskeleton.cpp
index d02705d9..bfa3a60f 100644
--- a/src/core/kcoreconfigskeleton.cpp
+++ b/src/core/kcoreconfigskeleton.cpp
@@ -167,6 +167,12 @@ bool KConfigSkeletonItem::isSaveNeeded() const
     return d->mIsSaveNeededImpl();
 }
 
+QVariant KConfigSkeletonItem::getDefault() const
+{
+    Q_D(const KConfigSkeletonItem);
+    return d->mGetDefaultImpl();
+}
+
 void KConfigSkeletonItem::readImmutability(const KConfigGroup &group)
 {
     Q_D(KConfigSkeletonItem);
@@ -185,6 +191,12 @@ void KConfigSkeletonItem::setIsSaveNeededImpl(const std::function<bool ()> &impl
     d->mIsSaveNeededImpl = impl;
 }
 
+void KConfigSkeletonItem::setGetDefaultImpl(const std::function<QVariant ()> &impl)
+{
+    Q_D(KConfigSkeletonItem);
+    d->mGetDefaultImpl = impl;
+}
+
 KPropertySkeletonItem::KPropertySkeletonItem(QObject *object, const QByteArray &propertyName, const QVariant &defaultValue)
     : KConfigSkeletonItem(*new KPropertySkeletonItemPrivate(object, propertyName, defaultValue), {}, {})
 {
@@ -196,6 +208,10 @@ KPropertySkeletonItem::KPropertySkeletonItem(QObject *object, const QByteArray &
         Q_D(const KPropertySkeletonItem);
         return d->mReference != d->mLoadedValue;
     });
+    setGetDefaultImpl([this] {
+        Q_D(const KPropertySkeletonItem);
+        return d->mDefaultValue;
+    });
 }
 
 QVariant KPropertySkeletonItem::property() const
@@ -1555,6 +1571,7 @@ KConfigCompilerSignallingItem::KConfigCompilerSignallingItem(KConfigSkeletonItem
 
     setIsDefaultImpl([this] { return mItem->isDefault(); });
     setIsSaveNeededImpl([this] { return mItem->isSaveNeeded(); });
+    setGetDefaultImpl([this] {return mItem->getDefault(); });
 }
 
 KConfigCompilerSignallingItem::~KConfigCompilerSignallingItem()
diff --git a/src/core/kcoreconfigskeleton.h b/src/core/kcoreconfigskeleton.h
index 9cf131b2..69f52060 100644
--- a/src/core/kcoreconfigskeleton.h
+++ b/src/core/kcoreconfigskeleton.h
@@ -230,6 +230,12 @@ public:
      */
     bool isSaveNeeded() const;
 
+    /**
+     * Returns the default value
+     * @since 5.74
+     */
+    QVariant getDefault() const;
+
 protected:
     explicit KConfigSkeletonItem(KConfigSkeletonItemPrivate &dd, const QString &_group, const QString &_key);
 
@@ -247,6 +253,7 @@ protected:
     // KF6: Use proper pure virtuals in KConfigSkeletonItem
     void setIsDefaultImpl(const std::function<bool()> &impl);
     void setIsSaveNeededImpl(const std::function<bool()> &impl);
+    void setGetDefaultImpl(const std::function<QVariant()> &impl);
 
     KConfigSkeletonItemPrivate *const d_ptr;
 };
@@ -324,6 +331,8 @@ public:
     {
         setIsDefaultImpl([this] { return mReference == mDefault; });
         setIsSaveNeededImpl([this] { return mReference != mLoadedValue; });
+        setGetDefaultImpl([this] { return QVariant::fromValue(mDefault); });
+
     }
 
     /**
diff --git a/src/core/kcoreconfigskeleton_p.h b/src/core/kcoreconfigskeleton_p.h
index 389bc4f7..006bd45f 100644
--- a/src/core/kcoreconfigskeleton_p.h
+++ b/src/core/kcoreconfigskeleton_p.h
@@ -54,6 +54,7 @@ public:
     // HACK: Necessary to avoid introducing new virtuals in KConfigSkeletonItem
     std::function<bool()> mIsDefaultImpl;
     std::function<bool()> mIsSaveNeededImpl;
+    std::function<QVariant()> mGetDefaultImpl;
 };
 
 class KPropertySkeletonItemPrivate : public KConfigSkeletonItemPrivate