QVector: Add assignment from std::initializer_list

Change-Id: I88a66e4b78ca6f40c328070f275e7163fb0d691c
Reviewed-by: Ville Voutilainen <ville.voutilainen@qt.io>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@qt.io>

3 files changed, 64 insertions, 1 deletions

diff --git a/src/corelib/tools/qvector.h b/src/corelib/tools/qvector.h
index 988d5a9e1b..9762ec1b5b 100644
--- a/src/corelib/tools/qvector.h
+++ b/src/corelib/tools/qvector.h
@@ -79,6 +79,7 @@ public:
     void swap(QVector<T> &other) Q_DECL_NOTHROW { qSwap(d, other.d); }
 #ifdef Q_COMPILER_INITIALIZER_LISTS
     inline QVector(std::initializer_list<T> args);
+    QVector<T> &operator=(std::initializer_list<T> args);
 #endif
     bool operator==(const QVector<T> &v) const;
     inline bool operator!=(const QVector<T> &v) const { return !(*this == v); }
@@ -542,10 +543,19 @@ QVector<T>::QVector(std::initializer_list<T> args)
         d = Data::sharedNull();
     }
 }
+
+template <typename T>
+QVector<T> &QVector<T>::operator=(std::initializer_list<T> args)
+{
+    QVector<T> tmp(args);
+    tmp.swap(*this);
+    return *this;
+}
+
 # if defined(Q_CC_MSVC)
 QT_WARNING_POP
 # endif // Q_CC_MSVC
-#endif // Q_COMPILER_INITALIZER_LISTS
+#endif // Q_COMPILER_INITIALIZER_LISTS
 
 template <typename T>
 void QVector<T>::freeData(Data *x)
diff --git a/src/corelib/tools/qvector.qdoc b/src/corelib/tools/qvector.qdoc
index 75b17a4207..69bbb5f9a2 100644
--- a/src/corelib/tools/qvector.qdoc
+++ b/src/corelib/tools/qvector.qdoc
@@ -263,6 +263,17 @@
     \since 5.2
 */
 
+/*!
+    \fn template <typename T> QVector<T> &QVector<T>::operator=(std::initializer_list<T> args)
+
+    Assigns the collection of values in \a args to this QVector instance.
+
+    This operator is only enabled if the compiler supports C++11 initializer
+    lists.
+
+    \since 5.14
+*/
+
 /*! \fn template <typename T> void QVector<T>::swap(QVector<T> &other)
     \since 4.8
 
diff --git a/tests/auto/corelib/tools/qvector/tst_qvector.cpp b/tests/auto/corelib/tools/qvector/tst_qvector.cpp
index a7faeb5ca5..2278e0ba13 100644
--- a/tests/auto/corelib/tools/qvector/tst_qvector.cpp
+++ b/tests/auto/corelib/tools/qvector/tst_qvector.cpp
@@ -206,6 +206,9 @@ private slots:
     void assignmentInt() const;
     void assignmentMovable() const;
     void assignmentCustom() const;
+    void assignFromInitializerListInt() const;
+    void assignFromInitializerListMovable() const;
+    void assignFromInitializerListCustom() const;
     void addInt() const;
     void addMovable() const;
     void addCustom() const;
@@ -330,6 +333,7 @@ private:
     template<typename T> void copyConstructor() const;
     template<typename T> void add() const;
     template<typename T> void append() const;
+    template<typename T> void assignFromInitializerList() const;
     template<typename T> void capacity() const;
     template<typename T> void clear() const;
     template<typename T> void count() const;
@@ -543,6 +547,44 @@ void tst_QVector::assignmentCustom() const
 }
 
 template<typename T>
+void tst_QVector::assignFromInitializerList() const
+{
+#ifdef Q_COMPILER_INITIALIZER_LISTS
+    T val1(SimpleValue<T>::at(1));
+    T val2(SimpleValue<T>::at(2));
+    T val3(SimpleValue<T>::at(3));
+
+    QVector<T> v1 = {val1, val2, val3};
+    QCOMPARE(v1, QVector<T>() << val1 << val2 << val3);
+    QCOMPARE(v1, (QVector<T> {val1, val2, val3}));
+
+    v1 = {};
+    QCOMPARE(v1.size(), 0);
+#else
+    QSKIP("This test requires support for C++11 initializer lists.");
+#endif
+}
+
+void tst_QVector::assignFromInitializerListInt() const
+{
+    assignFromInitializerList<int>();
+}
+
+void tst_QVector::assignFromInitializerListMovable() const
+{
+    const int instancesCount = Movable::counter.loadAcquire();
+    assignFromInitializerList<Movable>();
+    QCOMPARE(instancesCount, Movable::counter.loadAcquire());
+}
+
+void tst_QVector::assignFromInitializerListCustom() const
+{
+    const int instancesCount = Custom::counter.loadAcquire();
+    assignFromInitializerList<Custom>();
+    QCOMPARE(instancesCount, Custom::counter.loadAcquire());
+}
+
+template<typename T>
 void tst_QVector::add() const
 {
     {