1 files changed, 155 insertions, 0 deletions
diff --git a/src/corelib/kernel/qsequentialiterable.h b/src/corelib/kernel/qsequentialiterable.h
new file mode 100644
index 0000000000..dac146d2ad
--- /dev/null
+++ b/src/corelib/kernel/qsequentialiterable.h
@@ -0,0 +1,155 @@
+// Copyright (C) 2020 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QSEQUENTIALITERABLE_H
+#define QSEQUENTIALITERABLE_H
+
+#include <QtCore/qiterable.h>
+#include <QtCore/qvariant.h>
+
+QT_BEGIN_NAMESPACE
+
+class Q_CORE_EXPORT QSequentialIterator : public QIterator<QMetaSequence>
+{
+public:
+    using value_type = QVariant;
+    using reference = QVariantRef<QSequentialIterator>;
+    using pointer = QVariantPointer<QSequentialIterator>;
+
+    QSequentialIterator(QIterator &&it)
+        : QIterator(std::move(it))
+    {}
+
+    QVariantRef<QSequentialIterator> operator*() const;
+    QVariantPointer<QSequentialIterator> operator->() const;
+};
+
+class Q_CORE_EXPORT QSequentialConstIterator : public QConstIterator<QMetaSequence>
+{
+public:
+    using value_type = QVariant;
+    using reference = const QVariant &;
+    using pointer = QVariantConstPointer;
+
+    QSequentialConstIterator(QConstIterator &&it)
+        : QConstIterator(std::move(it))
+    {}
+
+    QVariant operator*() const;
+    QVariantConstPointer operator->() const;
+};
+
+class Q_CORE_EXPORT QSequentialIterable : public QIterable<QMetaSequence>
+{
+public:
+    using iterator = QTaggedIterator<QSequentialIterator, void>;
+    using const_iterator = QTaggedIterator<QSequentialConstIterator, void>;
+
+    using RandomAccessIterator = QTaggedIterator<iterator, std::random_access_iterator_tag>;
+    using BidirectionalIterator = QTaggedIterator<iterator, std::bidirectional_iterator_tag>;
+    using ForwardIterator = QTaggedIterator<iterator, std::forward_iterator_tag>;
+    using InputIterator = QTaggedIterator<iterator, std::input_iterator_tag>;
+
+    using RandomAccessConstIterator = QTaggedIterator<const_iterator, std::random_access_iterator_tag>;
+    using BidirectionalConstIterator = QTaggedIterator<const_iterator, std::bidirectional_iterator_tag>;
+    using ForwardConstIterator = QTaggedIterator<const_iterator, std::forward_iterator_tag>;
+    using InputConstIterator = QTaggedIterator<const_iterator, std::input_iterator_tag>;
+
+    template<class T>
+    QSequentialIterable(const T *p)
+        : QIterable(QMetaSequence::fromContainer<T>(), p)
+    {
+        Q_UNUSED(m_revision);
+    }
+
+    template<class T>
+    QSequentialIterable(T *p)
+        : QIterable(QMetaSequence::fromContainer<T>(), p)
+    {
+    }
+
+    QSequentialIterable()
+        : QIterable(QMetaSequence(), nullptr)
+    {
+    }
+
+    template<typename Pointer>
+    QSequentialIterable(const QMetaSequence &metaSequence, Pointer iterable)
+        : QIterable(metaSequence, iterable)
+    {
+    }
+
+    // ### Qt7: Pass QMetaType as value rather than const ref.
+    QSequentialIterable(const QMetaSequence &metaSequence, const QMetaType &metaType,
+                        void *iterable)
+        : QIterable(metaSequence, metaType.alignOf(), iterable)
+    {
+    }
+
+    // ### Qt7: Pass QMetaType as value rather than const ref.
+    QSequentialIterable(const QMetaSequence &metaSequence, const QMetaType &metaType,
+                        const void *iterable)
+        : QIterable(metaSequence, metaType.alignOf(), iterable)
+    {
+    }
+
+    QSequentialIterable(QIterable<QMetaSequence> &&other) : QIterable(std::move(other)) {}
+
+    QSequentialIterable &operator=(QIterable<QMetaSequence> &&other)
+    {
+        QIterable::operator=(std::move(other));
+        return *this;
+    }
+
+    const_iterator begin() const { return constBegin(); }
+    const_iterator end() const { return constEnd(); }
+
+    const_iterator constBegin() const { return const_iterator(QIterable::constBegin()); }
+    const_iterator constEnd() const { return const_iterator(QIterable::constEnd()); }
+
+    iterator mutableBegin() { return iterator(QIterable::mutableBegin()); }
+    iterator mutableEnd() { return iterator(QIterable::mutableEnd()); }
+
+    QVariant at(qsizetype idx) const;
+    void set(qsizetype idx, const QVariant &value);
+
+    enum Position { Unspecified, AtBegin, AtEnd };
+    void addValue(const QVariant &value, Position position = Unspecified);
+    void removeValue(Position position = Unspecified);
+
+    QMetaType valueMetaType() const;
+};
+
+template<>
+inline QVariantRef<QSequentialIterator>::operator QVariant() const
+{
+    if (m_pointer == nullptr)
+        return QVariant();
+    const QMetaType metaType(m_pointer->metaContainer().valueMetaType());
+    QVariant v(metaType);
+    void *dataPtr = metaType == QMetaType::fromType<QVariant>() ? &v : v.data();
+    m_pointer->metaContainer().valueAtIterator(m_pointer->constIterator(), dataPtr);
+    return v;
+}
+
+template<>
+inline QVariantRef<QSequentialIterator> &QVariantRef<QSequentialIterator>::operator=(
+        const QVariant &value)
+{
+    if (m_pointer == nullptr)
+        return *this;
+
+    QtPrivate::QVariantTypeCoercer coercer;
+    m_pointer->metaContainer().setValueAtIterator(
+                m_pointer->constIterator(),
+                coercer.coerce(value, m_pointer->metaContainer().valueMetaType()));
+    return *this;
+}
+
+Q_DECLARE_TYPEINFO(QSequentialIterable, Q_RELOCATABLE_TYPE);
+Q_DECLARE_TYPEINFO(QSequentialIterable::iterator, Q_RELOCATABLE_TYPE);
+Q_DECLARE_TYPEINFO(QSequentialIterable::const_iterator, Q_RELOCATABLE_TYPE);
+
+QT_END_NAMESPACE
+
+#endif // QSEQUENTIALITERABLE_H