DefaultEmptyArray Property Wrapper

DefaultEmptyArray.swift

import Foundation

@propertyWrapper
public struct DefaultEmptyArray<Element: Codable>: Codable {
    public var wrappedValue: [Element]
    
    public init(wrappedValue: [Element]) {
        self.wrappedValue = wrappedValue
    }
    
    public init(from decoder: Decoder) throws {
        let container = try decoder.singleValueContainer()
        self.wrappedValue = (try? container.decode([Element].self)) ?? []
    }
    
    public func encode(to encoder: Encoder) throws {
        try wrappedValue.encode(to: encoder)
    }
}

struct Employee: Codable {
    @DefaultEmptyArray var types: [EmployeeType]
}

enum EmployeeType: String, Codable {
    case HouseKeeping
    case Manager
    case Cashier
}

let employeeJSON = #"{ "types": ["Manager", "Cashier", "House-Keeping"] }"#.data(using: .utf8)!
let decodedResponse = try JSONDecoder().decode(Employee.self, from: employeeJSON)

print(decodedResponse)