Objective c 编写swift案例时，ordered to many关系的值类型不可接受

我正在从事一个项目，该项目要求我在现有文件结构上添加一个新的测试用例。现在我正在做一个测试用例，它需要进行api调用以获取维护信息

我得到的维护信息结构如下：

@objc(MaintenanceData)
class MaintenanceData: WebServiceEntity, Persistable {

static var contentId: ContentId = "maintenance"

@NSManaged var version: String
@NSManaged var maintenance: Bool
@NSManaged var maintenanceDescription: String?
@NSManaged var features: [FeatureMaintenanceData]?

public static func fieldMapping() -> [FieldName: String] {
    return [
        "version": "version",
        "maintenance": "maintenance",
        "maintenanceDescription": "maintenanceDescription",
        "features": "features"
    ]
}
}

@objc(FeatureMaintenanceData)
class FeatureMaintenanceData: WebServiceEntity, Persistable {

static var contentId: ContentId = "featureMaintenance"

@NSManaged var identifier: String
@NSManaged var maintenance: Bool
@NSManaged var maintenanceDescription: String?

public static func fieldMapping() -> [FieldName: String] {
    return [
        "identifier": "identifier",
        "maintenance": "maintenance",
        "maintenanceDescription": "maintenanceDescription"
    ]
}
}

@discardableResult func createAndInsertMaintenance(
    version: String = "",
    maintenance: Bool = false,
    maintenanceDescription: String? = nil,
    features: [FeatureMaintenanceData]? = nil,
) -> MaintenanceData {
    let maintenance = NSEntityDescription.insertNewObject(
        forEntityName: String(describing: MaintenanceData.self),
        into: managedObjectContext
    ) as! MaintenanceData

    maintenance.version = version
    maintenance.softUpdateMinimalVersion = softUpdateMinimalVersion
    maintenance.maintenance = maintenance
    maintenance.maintenanceDescription = maintenanceDescription
    maintenance.features = features <-----This is where error occurs

    return updateMaintenance
}

**出于安全原因，我更改了一些代码

现在我必须模拟一个假的

MaintenanceData

来测试

features

属性，它是

[FeatureMaintenanceData]

功能MaintenanceData

编写如下：

@objc(MaintenanceData)
class MaintenanceData: WebServiceEntity, Persistable {

static var contentId: ContentId = "maintenance"

@NSManaged var version: String
@NSManaged var maintenance: Bool
@NSManaged var maintenanceDescription: String?
@NSManaged var features: [FeatureMaintenanceData]?

public static func fieldMapping() -> [FieldName: String] {
    return [
        "version": "version",
        "maintenance": "maintenance",
        "maintenanceDescription": "maintenanceDescription",
        "features": "features"
    ]
}
}

@objc(FeatureMaintenanceData)
class FeatureMaintenanceData: WebServiceEntity, Persistable {

static var contentId: ContentId = "featureMaintenance"

@NSManaged var identifier: String
@NSManaged var maintenance: Bool
@NSManaged var maintenanceDescription: String?

public static func fieldMapping() -> [FieldName: String] {
    return [
        "identifier": "identifier",
        "maintenance": "maintenance",
        "maintenanceDescription": "maintenanceDescription"
    ]
}
}

@discardableResult func createAndInsertMaintenance(
    version: String = "",
    maintenance: Bool = false,
    maintenanceDescription: String? = nil,
    features: [FeatureMaintenanceData]? = nil,
) -> MaintenanceData {
    let maintenance = NSEntityDescription.insertNewObject(
        forEntityName: String(describing: MaintenanceData.self),
        into: managedObjectContext
    ) as! MaintenanceData

    maintenance.version = version
    maintenance.softUpdateMinimalVersion = softUpdateMinimalVersion
    maintenance.maintenance = maintenance
    maintenance.maintenanceDescription = maintenanceDescription
    maintenance.features = features <-----This is where error occurs

    return updateMaintenance
}

现在我需要模拟数据，

MockDataFactory

中有一个函数返回一个

MaintenanceData

对象，我需要使用它并将其传递给函数进行测试。函数编写如下：

@objc(MaintenanceData)
class MaintenanceData: WebServiceEntity, Persistable {

static var contentId: ContentId = "maintenance"

@NSManaged var version: String
@NSManaged var maintenance: Bool
@NSManaged var maintenanceDescription: String?
@NSManaged var features: [FeatureMaintenanceData]?

public static func fieldMapping() -> [FieldName: String] {
    return [
        "version": "version",
        "maintenance": "maintenance",
        "maintenanceDescription": "maintenanceDescription",
        "features": "features"
    ]
}
}

@objc(FeatureMaintenanceData)
class FeatureMaintenanceData: WebServiceEntity, Persistable {

static var contentId: ContentId = "featureMaintenance"

@NSManaged var identifier: String
@NSManaged var maintenance: Bool
@NSManaged var maintenanceDescription: String?

public static func fieldMapping() -> [FieldName: String] {
    return [
        "identifier": "identifier",
        "maintenance": "maintenance",
        "maintenanceDescription": "maintenanceDescription"
    ]
}
}

@discardableResult func createAndInsertMaintenance(
    version: String = "",
    maintenance: Bool = false,
    maintenanceDescription: String? = nil,
    features: [FeatureMaintenanceData]? = nil,
) -> MaintenanceData {
    let maintenance = NSEntityDescription.insertNewObject(
        forEntityName: String(describing: MaintenanceData.self),
        into: managedObjectContext
    ) as! MaintenanceData

    maintenance.version = version
    maintenance.softUpdateMinimalVersion = softUpdateMinimalVersion
    maintenance.maintenance = maintenance
    maintenance.maintenanceDescription = maintenanceDescription
    maintenance.features = features <-----This is where error occurs

    return updateMaintenance
}

但是，它返回一个错误

对于ordered-to-many关系不可接受的值类型：property=“features”；所需类型=传感器数据集

既然我不知道Obj-c，有人能给我解释一下问题是什么以及如何解决吗？非常感谢