swift - API 违规 - 多次调用 -[XCTestExpectation fulfill]

Question

我正在用 Swift 编写我的第一个集成测试。

我正在尝试检查特定 url 中是否存在图像。

我想执行一个头部请求并检查响应的状态码。

我不断收到错误:

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'API violation - multiple calls made to -[XCTestExpectation fulfill].

我试过让期望成为一个弱变量。

我有以下代码/测试:

func testAndroidImagesExist() {
 weak var expectation: XCTestExpectation?
 expectation =  expectationForNotification(kBaoNotification_ManifestImportCompleted, object: nil) { (notification: NSNotification!) -> Bool in

 let userInfo: NSDictionary = notification.userInfo!
 var titles = userInfo.valueForKey("titles") as? NSArray
 titles?.enumerateObjectsUsingBlock({ (t: AnyObject!, idx: Int, stop: UnsafeMutablePointer<ObjCBool>) -> Void in
  let title = t as NSDictionary

  let titleLabel = title.valueForKey("title") as String
  let parameters = title.valueForKey("parameters") as NSDictionary
  let androidImageUrl = parameters.valueForKey("android_logo_url") as String
  var androidRequest = NSMutableURLRequest(URL: NSURL(string: androidImageUrl)!)
  androidRequest.HTTPMethod = "HEAD"
  var androidResponse: NSURLResponse?
  var androidData = NSURLConnection.sendSynchronousRequest(androidRequest, returningResponse: &androidResponse, error: nil)
  var androidHttpResponse = androidResponse as? NSHTTPURLResponse

  if androidHttpResponse != nil {
   if androidHttpResponse!.statusCode == 404 {
    XCTFail("Android image not found for title \(titleLabel)")
   }
  } else {
   XCTFail("No response from android image for title \(titleLabel)")
  }
 })
 expectation?.fulfill()
 return true
}
 waitForExpectationsWithTimeout(10, handler: { (error: NSError!) -> Void in
  if (error != nil) {
   XCTFail("Timeout error: \(error)")
  }
 }) 
}

有什么想法吗？

Answer 1

我建议处理多次发生的期望的最佳方式是在 fulfill 之后将期望变量设置为 nil。然后，后续调用将被忽略。

目标-C:

// Fulfill and remove. Subsequent messages to nil are ignored.
[multiEx fulfill];
multiEx = nil;`

swift :

// Fulfill and remove. Optional chaining ends execution on nil.
var multiEx:XCTestExpectation? = expectationWithDescription("multiEx")
...
multiEx?.fulfill() 
multiEx = nil