// We do same-document navigation if going to a different item and if either of the following is true:
// - The other item corresponds to the same document (for history entries created via pushState or fragment changes).
// - The other item corresponds to the same set of documents, including frames (for history entries created via regular navigation)
bool HistoryItem::shouldDoSameDocumentNavigationTo(HistoryItem* otherItem) const
{
if (this == otherItem)
return false;
if (stateObject() || otherItem->stateObject())
return documentSequenceNumber() == otherItem->documentSequenceNumber();
if ((url().hasFragmentIdentifier() || otherItem->url().hasFragmentIdentifier()) && equalIgnoringFragmentIdentifier(url(), otherItem->url()))
return documentSequenceNumber() == otherItem->documentSequenceNumber();
return hasSameDocumentTree(otherItem);
}
// Does a recursive check that this item and its descendants have the same
// document sequence numbers as the other item.
bool HistoryItem::hasSameDocumentTree(HistoryItem* otherItem) const
{
if (documentSequenceNumber() != otherItem->documentSequenceNumber())
return false;
if (children().size() != otherItem->children().size())
return false;
for (size_t i = 0; i < children().size(); i++) {
HistoryItem* child = children()[i].get();
HistoryItem* otherChild = otherItem->childItemWithDocumentSequenceNumber(child->documentSequenceNumber());
if (!otherChild || !child->hasSameDocumentTree(otherChild))
return false;
}
return true;
}
// Does a recursive check that this item and its descendants have the same
// document sequence numbers as the other item.
bool HistoryItem::hasSameDocumentTree(HistoryItem& otherItem) const
{
if (documentSequenceNumber() != otherItem.documentSequenceNumber())
return false;
if (children().size() != otherItem.children().size())
return false;
for (size_t i = 0; i < children().size(); i++) {
auto& child = children()[i].get();
auto* otherChild = otherItem.childItemWithDocumentSequenceNumber(child.documentSequenceNumber());
if (!otherChild || !child.hasSameDocumentTree(*otherChild))
return false;
}
return true;
}
