Have Ratings be gadgets rather than QObjects

Should make the instances much lighter, which is important as there's
tons of them.

BUG: 431364

libdiscover/ReviewsBackend/Rating.cpp

@@ -79,8 +79,7 @@ double dampenedRating(int ratings[6], double power = 0.1)
 }
 
 Rating::Rating(const QString &packageName, quint64 ratingCount, int data[6])
-    : QObject()
-    , m_packageName(packageName)
+    : m_packageName(packageName)
     , m_ratingCount(ratingCount)
     // TODO consider storing data[] and present in UI
     , m_rating(((data[1] + (data[2] * 2) +
@@ -100,8 +99,7 @@ Rating::Rating(const QString &packageName, quint64 ratingCount, int data[6])
 }
 
 Rating::Rating(const QString &packageName, quint64 ratingCount, int rating)
-    : QObject()
-    , m_packageName(packageName)
+    : m_packageName(packageName)
     , m_ratingCount(ratingCount)
     , m_rating(rating)
     , m_ratingPoints(rating)

libdiscover/ReviewsBackend/Rating.h

@@ -12,17 +12,18 @@
 
 #include "discovercommon_export.h"
 
-class DISCOVERCOMMON_EXPORT Rating : public QObject
+class DISCOVERCOMMON_EXPORT Rating
 {
-Q_OBJECT
+Q_GADGET
 Q_PROPERTY(double sortableRating READ sortableRating CONSTANT)
 Q_PROPERTY(float rating READ rating CONSTANT)
 Q_PROPERTY(int ratingPoints READ ratingPoints CONSTANT)
 Q_PROPERTY(quint64 ratingCount READ ratingCount CONSTANT)
 public:
+    Rating() {}
     explicit Rating(const QString &packageName, quint64 ratingCount, int rating);
     explicit Rating(const QString &packageName, quint64 ratingCount, int data[6]);
-    ~Rating() override;
+    ~Rating();
 
     QString packageName() const;
     quint64 ratingCount() const;
@@ -34,10 +35,12 @@ public:
 
 private:
     const QString m_packageName;
-    const quint64 m_ratingCount;
-    const float m_rating;
-    int m_ratingPoints;
-    double m_sortableRating;
+    const quint64 m_ratingCount = 0;
+    const float m_rating = 0;
+    int m_ratingPoints = 0;
+    double m_sortableRating = 0;
 };
 
+Q_DECLARE_METATYPE(Rating)
+
 #endif

libdiscover/appstream/OdrsReviewsBackend.cpp

@@ -64,6 +64,11 @@ OdrsReviewsBackend::OdrsReviewsBackend()
     }
 }
 
+OdrsReviewsBackend::~OdrsReviewsBackend() noexcept
+{
+    qDeleteAll(m_ratings);
+}
+
 void OdrsReviewsBackend::ratingsFetched(KJob *job)
 {
     m_isFetching = false;
@@ -255,7 +260,6 @@ void OdrsReviewsBackend::parseRatings()
                                 appJsonObject.value(QLatin1String("star5")).toInt() };
 
             Rating *rating = new Rating(it.key(), ratingCount, ratingMap);
-            rating->setParent(this);
             m_ratings.insert(it.key(), rating);
         }
         ratingsDocument.close();

libdiscover/appstream/OdrsReviewsBackend.h

@@ -24,6 +24,7 @@ class DISCOVERCOMMON_EXPORT OdrsReviewsBackend : public AbstractReviewsBackend
 Q_OBJECT
 public:
     explicit OdrsReviewsBackend();
+    ~OdrsReviewsBackend() override;
 
     QString userName() const override;
     void login() override {}

libdiscover/backends/DummyBackend/DummyReviewsBackend.cpp

@@ -17,6 +17,11 @@ DummyReviewsBackend::DummyReviewsBackend(DummyBackend* parent)
     : AbstractReviewsBackend(parent)
 {}
 
+DummyReviewsBackend::~DummyReviewsBackend() noexcept
+{
+    qDeleteAll(m_ratings);
+}
+
 void DummyReviewsBackend::fetchReviews(AbstractResource* app, int page)
 {
     if (page>=5)
@@ -46,7 +51,6 @@ void DummyReviewsBackend::initialize()
 
         int ratings[] = {0,0,0,0,0, randomRating};
         Rating* rating = new Rating(app->packageName(), ++i, ratings);
-        rating->setParent(this);
         m_ratings.insert(app, rating);
         Q_EMIT app->ratingFetched();
     }

libdiscover/backends/DummyBackend/DummyReviewsBackend.h

@@ -17,6 +17,7 @@ class DummyReviewsBackend : public AbstractReviewsBackend
 Q_OBJECT
 public:
     explicit DummyReviewsBackend(DummyBackend* parent = nullptr);
+    ~DummyReviewsBackend() override;
 
     QString userName() const override { return QStringLiteral("dummy"); }
     void login() override {}

libdiscover/backends/KNSBackend/KNSResource.cpp

@@ -243,13 +243,13 @@ Rating * KNSResource::ratingInstance()
         const int noc = m_entry.numberOfComments();
         const int rating = m_entry.rating();
         Q_ASSERT(rating <= 100);
-        return new Rating(
+        m_rating.reset(new Rating(
             packageName(),
             noc,
             rating / 10
-        );
+        ));
     }
-    return m_rating;
+    return m_rating.data();
 }
 
 QString KNSResource::author() const

libdiscover/backends/KNSBackend/KNSResource.h

@@ -64,7 +64,7 @@ private:
     const QStringList m_categories;
     KNSCore::EntryInternal m_entry;
     KNS3::Entry::Status m_lastStatus;
-    QPointer<Rating> m_rating;
+    QScopedPointer<Rating> m_rating;
 };
 
 #endif // KNSRESOURCE_H

libdiscover/resources/AbstractResource.cpp

@@ -7,6 +7,7 @@
 #include "AbstractResource.h"
 #include "AbstractResourcesBackend.h"
 #include <ReviewsBackend/AbstractReviewsBackend.h>
+#include <ReviewsBackend/Rating.h>
 #include <Category/CategoryModel.h>
 #include <KLocalizedString>
 #include <KFormat>
@@ -110,6 +111,12 @@ Rating* AbstractResource::rating() const
     return ratings ? ratings->ratingForApplication(const_cast<AbstractResource*>(this)) : nullptr;
 }
 
+QVariant AbstractResource::ratingVariant() const
+{
+    auto instance = rating();
+    return instance ? QVariant::fromValue<Rating>(*instance) : QVariant();
+}
+
 QStringList AbstractResource::extends() const
 {
     return {};

libdiscover/resources/AbstractResource.h

@@ -60,7 +60,7 @@ class DISCOVERCOMMON_EXPORT AbstractResource : public QObject
     Q_PROPERTY(QString section READ section CONSTANT)
     Q_PROPERTY(QStringList mimetypes READ mimetypes CONSTANT)
     Q_PROPERTY(AbstractResourcesBackend* backend READ backend CONSTANT)
-    Q_PROPERTY(Rating* rating READ rating NOTIFY ratingFetched)
+    Q_PROPERTY(QVariant rating READ ratingVariant NOTIFY ratingFetched)
     Q_PROPERTY(QString appstreamId READ appstreamId CONSTANT)
     Q_PROPERTY(QString categoryDisplay READ categoryDisplay CONSTANT)
     Q_PROPERTY(QUrl url READ url CONSTANT)
@@ -181,6 +181,7 @@ class DISCOVERCOMMON_EXPORT AbstractResource : public QObject
          * @returns the rating for the resource or null if not available
          */
         Rating* rating() const;
+        QVariant ratingVariant() const;
 
         /**
          * @returns a string defining the categories the resource belongs to

libdiscover/resources/ResourcesProxyModel.cpp

@@ -458,9 +458,9 @@ QVariant ResourcesProxyModel::roleToValue(AbstractResource* resource, int role)
             const int idx = Rating::staticMetaObject.indexOfProperty(roleNames().value(role).constData());
             Q_ASSERT(idx >= 0);
             auto prop = Rating::staticMetaObject.property(idx);
-            if (rating)
-                return prop.read(rating);
-            else {
+            if (rating) {
+                return prop.readOnGadget(rating);
+            } else {
                 QVariant val(0);
                 val.convert(prop.type());
                 return val;