使用示例核心数据进行单元测试

Question

这是我的 XCTestCase 的开始 class:

var moc: NSManagedObjectContext!

    override func setUp() {
        super.setUp()

        moc = self.setUpInMemoryManagedObjectContext()
        self.fillManagedObjectContextWithExampleData(moc)
    }

    func setUpInMemoryManagedObjectContext() -> NSManagedObjectContext {

        let modelName = "ProjectApp"
        let modelURL = NSBundle.mainBundle().URLForResource(modelName, withExtension:"momd")!
        let managedObjectModel = NSManagedObjectModel(contentsOfURL: modelURL)!

        let persistentStoreCoordinator = NSPersistentStoreCoordinator(managedObjectModel: managedObjectModel)
        persistentStoreCoordinator.addPersistentStoreWithType(NSInMemoryStoreType, configuration: nil, URL: nil, options: nil, error: nil)

        let managedObjectContext = NSManagedObjectContext()
        managedObjectContext.persistentStoreCoordinator = persistentStoreCoordinator

        return managedObjectContext
    }

    func fillManagedObjectContextWithExampleData(context: NSManagedObjectContext) {
        // var firstSC = NSEntityDescription..insertNewObjectForEntityForName("StaticContent", inManagedObjectContext: context) as! StaticContent
        var staticContentEntity = NSEntityDescription.entityForName("StaticContent", inManagedObjectContext: context)!

        var firstSC = StaticContent(entity: staticContentEntity, insertIntoManagedObjectContext: context)
        firstSC.name = "First Name"

        var secondSC = StaticContent(entity: staticContentEntity, insertIntoManagedObjectContext: context)
        secondSC.name = "Second Name"

        var error: NSError? = nil

        if context.save(&error) {
            return
        }
    }

我只想创建 managedObjectContext（在内存中，仅用于测试）并用示例数据填充它。所以我可以使用：

managedObjectContext.executeFetchRequest(fetchRequest, error: nil) as! [StaticContent]

在我的单元测试中。它执行但是当我调用需要 [StaticContent] 的函数时我得到一个错误：

fatal error: NSArray element failed to match the Swift Array Element type

那么这有什么问题呢？我调用的函数工作正常。当我在我的应用程序中而不是在单元测试中使用它时，我没有问题。那我做错了什么？

Answer 1

我真的不想回答我的问题，但我找到了答案，我想帮助其他人。我找到了一部分代码，它根据实体运行的目标更改实体 class 的名称。所以我在创建 NSManagedObjectModel 的地方添加了这些代码行，它有助于：

    // Create the module name
    let moduleName = "ProjectAppTests"

    // Create a new managed object model with updated entity class names
    var newEntities = [] as [NSEntityDescription]
    for (_, entity) in enumerate(managedObjectModel.entities) {
        let newEntity = entity.copy() as! NSEntityDescription
        newEntity.managedObjectClassName = "\(moduleName).\(entity.name)"
        newEntities.append(newEntity)
    }
    let newManagedObjectModel = NSManagedObjectModel()
    newManagedObjectModel.entities = newEntities

    let persistentStoreCoordinator = NSPersistentStoreCoordinator(managedObjectModel: newManagedObjectModel)

不知道为什么使用 Swift 的 Core Data 中的 Class 名称如此复杂。但它有帮助，现在可以正常工作了。

Answer 2

在 swift 3.0 中： </p> <pre><code>func setUpInMemoryManagedObjectContext() -> NSManagedObjectContext { let moduleName = "Model" do { let managedObjectContext = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType) let modelURL = Bundle.main.url(forResource: moduleName, withExtension:"momd") let newObjectModel = NSManagedObjectModel.init(contentsOf: modelURL!) let persistentStoreCoordinator = NSPersistentStoreCoordinator(managedObjectModel : newObjectModel!) try persistentStoreCoordinator.addPersistentStore(ofType: NSInMemoryStoreType, configurationName: nil, at: nil, options: nil) managedObjectContext.persistentStoreCoordinator = persistentStoreCoordinator return managedObjectContext } catch let error as NSError { logErr(error.localizedDescription) XCTFail() } XCTFail("failed to created mocked coreData (inMemroy)") return NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType) } func fillManagedObjectContextWithExampleData(context: NSManagedObjectContext) { //lets assume you got some Food POJO class do { let foodJson: NSDictionary = ["id" : "1" , "foodId" : "1" , "displayName": "Pizza"] let firstFood = try Food.createOrUpdate(dict: foodJson, inManagedObjectContext: context) try context.save() return } catch let error as NSError { logErr(error.localizedDescription) } }

使用示例核心数据进行单元测试

Unit test with example Core Data

ios

swift

unit-testing

core-data

nsmanagedobjectcontext