withKeyOf<T extends DataModelMixin<T>> static method

T withKeyOf<T extends DataModelMixin<T>>({ required T source, required T destination, })

Apply source's key to destination.

Implementation

static T withKeyOf<T extends DataModelMixin<T>>(
    {required T source, required T destination}) {
  if (source._key == null) {
    throw Exception("Model must be initialized:\n\n$source");
  }

  final graph = source._remoteAdapter.graph;
  final type = source._internalType;

  // ONLY data we keep from source is its key
  // ONLY data we remove from destination is its key
  if (source._key != destination._key) {
    final destKey = destination._key;

    // assign correct key to destination
    destination._key = source._key;

    // migrate relationships to new key
    destination._remoteAdapter.localAdapter._initializeRelationships(
      destination,
      from: source,
    );

    if (destKey != null) {
      // remove node
      graph._removeNode(destKey);
    }

    if (destination.id != null) {
      // if present, remove existent ID association
      graph.removeId(type, destination.id!, notify: false);
      // and associate ID with source key
      graph.getKeyForId(type, destination.id, keyIfAbsent: source._key);
    }
  }
  return destination;
}