Deprecate conversion functions between QList and QSet

Users should use range constructors instead to do the conversion.
Keep conversion methods between QList and QVector as these will turn
into a no-op in Qt 6, whereas forcing people to use range constructors
would lead to deep copies of the data.

Change-Id: Id9fc9e4d007044e019826da523e8418857c91283
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

5 files changed, 53 insertions, 14 deletions

diff --git a/tests/auto/corelib/tools/collections/tst_collections.cpp b/tests/auto/corelib/tools/collections/tst_collections.cpp
index 9bd90d21cd..734b018b39 100644
--- a/tests/auto/corelib/tools/collections/tst_collections.cpp
+++ b/tests/auto/corelib/tools/collections/tst_collections.cpp
@@ -2531,14 +2531,18 @@ void tst_Collections::conversions()
         QCOMPARE(list2.size(), 4);
         QVERIFY(list2 == (QList<QString>() << STUFF));
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
         QSet<QString> set1 = list1.toSet();
+#else
+        QSet<QString> set1(list1.begin(), list1.end());
+#endif
         QCOMPARE(set1.size(), 3);
         QVERIFY(set1.contains("A"));
         QVERIFY(set1.contains("B"));
         QVERIFY(set1.contains("C"));
         QVERIFY(!set1.contains("D"));
 
-        QList<QString> list3 = set1.toList();
+        QList<QString> list3 = set1.values();
         QCOMPARE(list3.size(), 3);
         QVERIFY(list3.contains("A"));
         QVERIFY(list3.contains("B"));
@@ -2546,9 +2550,11 @@ void tst_Collections::conversions()
         QVERIFY(!list3.contains("D"));
 
         QVERIFY(QList<int>().toVector().isEmpty());
-        QVERIFY(QList<int>().toSet().isEmpty());
         QVERIFY(QVector<int>().toList().isEmpty());
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
+        QVERIFY(QList<int>().toSet().isEmpty());
         QVERIFY(QSet<int>().toList().isEmpty());
+#endif
     }
 
     {
@@ -2563,14 +2569,22 @@ void tst_Collections::conversions()
         QCOMPARE(list2.size(), 4);
         QVERIFY(list2 == (QList<QString>() << STUFF));
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
         QSet<QString> set1 = QSet<QString>::fromList(list1);
+#else
+        QSet<QString> set1(list1.begin(), list1.end());
+#endif
         QCOMPARE(set1.size(), 3);
         QVERIFY(set1.contains("A"));
         QVERIFY(set1.contains("B"));
         QVERIFY(set1.contains("C"));
         QVERIFY(!set1.contains("D"));
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
         QList<QString> list3 = QList<QString>::fromSet(set1);
+#else
+        QList<QString> list3 = set1.values();
+#endif
         QCOMPARE(list3.size(), 3);
         QVERIFY(list3.contains("A"));
         QVERIFY(list3.contains("B"));
@@ -2578,9 +2592,11 @@ void tst_Collections::conversions()
         QVERIFY(!list3.contains("D"));
 
         QVERIFY(QVector<int>::fromList(QList<int>()).isEmpty());
-        QVERIFY(QSet<int>::fromList(QList<int>()).isEmpty());
         QVERIFY(QList<int>::fromVector(QVector<int>()).isEmpty());
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
+        QVERIFY(QSet<int>::fromList(QList<int>()).isEmpty());
         QVERIFY(QList<int>::fromSet(QSet<int>()).isEmpty());
+#endif
     }
 #undef STUFF
 }
@@ -2776,15 +2792,21 @@ void tst_Collections::vector_stl()
     for (int i = 0; i < elements.count(); ++i)
         vector << elements.at(i);
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     std::vector<QString> stdVector = vector.toStdVector();
-
+#else
+    std::vector<QString> stdVector(vector.begin(), vector.end());
+#endif
     QCOMPARE(int(stdVector.size()), elements.size());
 
     std::vector<QString>::const_iterator it = stdVector.begin();
     for (uint j = 0; j < stdVector.size() && it != stdVector.end(); ++j, ++it)
         QCOMPARE(*it, vector[j]);
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     QCOMPARE(QVector<QString>::fromStdVector(stdVector), vector);
+#endif
+    QCOMPARE(QVector<QString>(stdVector.begin(), stdVector.end()), vector);
 }
 
 void tst_Collections::linkedlist_stl_data()
@@ -2830,7 +2852,11 @@ void tst_Collections::list_stl()
     for (int i = 0; i < elements.count(); ++i)
         list << elements.at(i);
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     std::list<QString> stdList = list.toStdList();
+#else
+    std::list<QString> stdList(list.begin(), list.end());
+#endif
 
     QCOMPARE(int(stdList.size()), elements.size());
 
@@ -2838,7 +2864,10 @@ void tst_Collections::list_stl()
     for (uint j = 0; j < stdList.size() && it != stdList.end(); ++j, ++it)
         QCOMPARE(*it, list[j]);
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     QCOMPARE(QList<QString>::fromStdList(stdList), list);
+#endif
+    QCOMPARE(QList<QString>(stdList.begin(), stdList.end()), list);
 }
 
 template <typename T>
diff --git a/tests/auto/corelib/tools/qlist/tst_qlist.cpp b/tests/auto/corelib/tools/qlist/tst_qlist.cpp
index 7fb3e67462..5a485e88d2 100644
--- a/tests/auto/corelib/tools/qlist/tst_qlist.cpp
+++ b/tests/auto/corelib/tools/qlist/tst_qlist.cpp
@@ -364,10 +364,10 @@ private slots:
     void takeLastOptimal() const;
     void takeLastMovable() const;
     void takeLastComplex() const;
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     void toSetOptimal() const;
     void toSetMovable() const;
     void toSetComplex() const;
-#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     void toStdListOptimal() const;
     void toStdListMovable() const;
     void toStdListComplex() const;
@@ -428,8 +428,8 @@ private:
     template<typename T> void takeAt() const;
     template<typename T> void takeFirst() const;
     template<typename T> void takeLast() const;
-    template<typename T> void toSet() const;
 #if QT_VERSION < QT_VERSION_CHECK(6,0,0)
+    template<typename T> void toSet() const;
     template<typename T> void toStdList() const;
 #endif
     template<typename T> void toVector() const;
@@ -1599,6 +1599,7 @@ void tst_QList::takeLastComplex() const
     QCOMPARE(liveCount, Complex::getLiveCount());
 }
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
 template<typename T>
 void tst_QList::toSet() const
 {
@@ -1637,7 +1638,6 @@ void tst_QList::toSetComplex() const
     QCOMPARE(liveCount, Complex::getLiveCount());
 }
 
-#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
 template<typename T>
 void tst_QList::toStdList() const
 {
diff --git a/tests/auto/gui/qopenglconfig/tst_qopenglconfig.cpp b/tests/auto/gui/qopenglconfig/tst_qopenglconfig.cpp
index f8dfdbd3b0..b82b277781 100644
--- a/tests/auto/gui/qopenglconfig/tst_qopenglconfig.cpp
+++ b/tests/auto/gui/qopenglconfig/tst_qopenglconfig.cpp
@@ -200,7 +200,7 @@ static void dumpGlConfiguration(QOpenGLContext &context, QTextStream &str)
         << "\nShading language : " << reinterpret_cast<const char *>(functions.glGetString(GL_SHADING_LANGUAGE_VERSION))
         << "\nFormat           : " << context.format();
 
-    QList<QByteArray> extensionList = context.extensions().toList();
+    QList<QByteArray> extensionList = context.extensions().values();
     std::sort(extensionList.begin(), extensionList.end());
     const int extensionCount = extensionList.size();
     str << "\n\nFound " << extensionCount << " extensions:\n";
@@ -233,9 +233,9 @@ void tst_QOpenGlConfig::testGlConfiguration()
 static inline QByteArray msgSetMismatch(const QSet<QString> &expected,
                                         const QSet<QString> &actual)
 {
-    const QString result = QStringList(expected.toList()).join(QLatin1Char(','))
+    const QString result = QStringList(expected.values()).join(QLatin1Char(','))
         + QLatin1String(" != ")
-        + QStringList(actual.toList()).join(QLatin1Char(','));
+        + QStringList(actual.values()).join(QLatin1Char(','));
     return result.toLatin1();
 }
 
diff --git a/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp b/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp
index e57ac77c39..af70b653ee 100644
--- a/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp
+++ b/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp
@@ -908,7 +908,9 @@ void tst_QApplication::libraryPaths()
 
         QStringList actual = QApplication::libraryPaths();
         actual.sort();
-        QStringList expected = QSet<QString>::fromList((QStringList() << testDir << appDirPath)).toList();
+        QStringList expected;
+        expected << testDir << appDirPath;
+        expected = QSet<QString>(expected.constBegin(), expected.constEnd()).values();
         expected.sort();
 
         QVERIFY2(isPathListIncluded(actual, expected),
@@ -925,7 +927,9 @@ void tst_QApplication::libraryPaths()
         QStringList actual = QApplication::libraryPaths();
         actual.sort();
 
-        QStringList expected = QSet<QString>::fromList((QStringList() << installPathPlugins << appDirPath)).toList();
+        QStringList expected;
+        expected << installPathPlugins << appDirPath;
+        expected = QSet<QString>(expected.constBegin(), expected.constEnd()).values();
         expected.sort();
 
 #ifdef Q_OS_WINRT
diff --git a/tests/auto/widgets/widgets/qabstractscrollarea/tst_qabstractscrollarea.cpp b/tests/auto/widgets/widgets/qabstractscrollarea/tst_qabstractscrollarea.cpp
index 007825d39c..a17a9f6c33 100644
--- a/tests/auto/widgets/widgets/qabstractscrollarea/tst_qabstractscrollarea.cpp
+++ b/tests/auto/widgets/widgets/qabstractscrollarea/tst_qabstractscrollarea.cpp
@@ -124,13 +124,19 @@ void tst_QAbstractScrollArea::scrollBarWidgets()
     QCOMPARE(area.scrollBarWidgets(Qt::AlignTop), QWidgetList());
     QCOMPARE(area.scrollBarWidgets(Qt::AlignBottom), w2List);
 
+    auto sort = [](const QWidgetList l) {
+        QWidgetList list = l;
+        std::sort(list.begin(), list.end());
+        return list;
+    };
+
     // two widgets at Bottom.
     area.addScrollBarWidget(w3, Qt::AlignBottom);
-    QCOMPARE(area.scrollBarWidgets(all).toSet(), allList.toSet());
+    QCOMPARE(sort(area.scrollBarWidgets(all)), sort(allList));
     QCOMPARE(area.scrollBarWidgets(Qt::AlignLeft), w1List);
     QCOMPARE(area.scrollBarWidgets(Qt::AlignRight), QWidgetList());
     QCOMPARE(area.scrollBarWidgets(Qt::AlignTop), QWidgetList());
-    QCOMPARE(area.scrollBarWidgets(Qt::AlignBottom).toSet(), (w2List + w3List).toSet());
+    QCOMPARE(sort(area.scrollBarWidgets(Qt::AlignBottom)), sort(w2List + w3List));
 
     //delete
     delete w1;