Sort is swift doubles the number of entries in array

class InventoryModel: ObservableObject {

    @Published var fileData = [inventoryEntry]()

    var fileData2 = [inventoryEntry]() // for debug viewing fileData

    var fileData3 = [inventoryEntry]() // for debug viewing fileData

.....
}



struct inventoryEntry{

    var id: UUID = UUID()

    var name: String = ""

    var catagory: String = ""

    var subcatagory: String = ""

    var location: String = ""

}



inventoryModel.fileData.sort{$0.name < $1.name}



before sort the array has 64 entries and it is also stored in fileData2 viewable at break point

after sort the array has 127 entries and I store hit in fileData3 viewable at break point



What happened here. I did not expect sorting the array to add copied entries



I consider this a bug. bug?