comparedOf static method

Map<String, List<ChartLabeledData>> comparedOf(
  1. List<ChartLabeledData> oldList,
  2. List<ChartLabeledData> newList
)

Implementation

static Map<String, List<ChartLabeledData>> comparedOf(List<ChartLabeledData> oldList, List<ChartLabeledData> newList) {
  final oldMap = {for (var item in oldList) item.label: item};
  final newMap = {for (var item in newList) item.label: item};

  final removed = oldMap.keys.where((label) => !newMap.containsKey(label)).map((label) => oldMap[label]!).toList();
  final created = newMap.keys.where((label) => !oldMap.containsKey(label)).map((label) => newMap[label]!).toList();
  final changed = newMap.keys
    .where((label) => oldMap.containsKey(label) && !((oldMap[label]!) == (newMap[label]!)))
    .map((label) => newMap[label]!)
    .toList();

  return {"removed": removed, "created": created, "changed": changed};
}