ValuePtr ModuleMerger::lastInNextChain(const ValuePtr &v)
{
    ValuePtr n = v;
    while (n->next())
        n = n->next();
    return n;
}
void ModuleMerger::insertProperties(Item::PropertyMap *dst, Item *srcItem, PropertiesType type)
{
    QSet<const Item *> &seenInstances
            = type == ScalarProperties ? m_seenInstancesTopDown : m_seenInstancesBottomUp;
    Item *origSrcItem = srcItem;
    do {
        if (!seenInstances.contains(srcItem)) {
            seenInstances.insert(srcItem);
            for (Item::PropertyMap::const_iterator it = srcItem->properties().constBegin();
                 it != srcItem->properties().constEnd(); ++it) {
                const ValuePtr &srcVal = it.value();
                if (srcVal->type() != Value::JSSourceValueType)
                    continue;
                const PropertyDeclaration srcDecl = srcItem->propertyDeclaration(it.key());
                if (!srcDecl.isValid() || srcDecl.isScalar() != (type == ScalarProperties))
                    continue;
                ValuePtr &v = (*dst)[it.key()];
                if (v && type == ScalarProperties)
                    continue;
                ValuePtr clonedVal = srcVal->clone();
                m_decls[clonedVal] = srcDecl;
                clonedVal->setDefiningItem(origSrcItem);
                if (v) {
                    QBS_CHECK(!clonedVal->next());
                    clonedVal->setNext(v);
                }
                v = clonedVal;
            }
        }
        srcItem = srcItem->prototype();
    } while (srcItem && srcItem->type() == ItemType::ModuleInstance);
}