void IDBTransaction::indexDeleted(IDBIndex* index) {
DCHECK(index);
DCHECK(!index->isDeleted()) << "indexDeleted called twice for the same index";
IDBObjectStore* objectStore = index->objectStore();
DCHECK_EQ(objectStore->transaction(), this);
DCHECK(m_objectStoreMap.contains(objectStore->name()))
<< "An index was deleted without accessing its object store";
const auto& objectStoreIterator = m_oldStoreMetadata.find(objectStore);
if (objectStoreIterator == m_oldStoreMetadata.end()) {
// The index's object store was created in this transaction, so this
// index was also created (and deleted) in this transaction, and will
// not be restored if the transaction aborts.
//
// Subtle proof for the first sentence above: Deleting an index requires
// calling deleteIndex() on the store's IDBObjectStore instance.
// Whenever we create an IDBObjectStore instance for a previously
// created store, we snapshot the store's metadata. So, deleting an
// index of an "old" store can only be done after the store's metadata
// is snapshotted.
return;
}
const IDBObjectStoreMetadata* oldStoreMetadata =
objectStoreIterator->value.get();
DCHECK(oldStoreMetadata);
if (!oldStoreMetadata->indexes.contains(index->id())) {
// The index's object store was created before this transaction, but the
// index was created (and deleted) in this transaction, so it will not
// be restored if the transaction aborts.
return;
}
m_deletedIndexes.append(index);
}
