如何在 Swift 中对这个自定义 UITextField 进行单元测试？

我创建了一个像这样的自定义 UITextField

import Foundation
import UIKit

class NoZeroTextField: UITextField, UITextFieldDelegate {
    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        self.delegate = self
    }

    func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
    if (string == "0" ) {
        //ignore input
        return false
    }
        return true
    }
}

我正在尝试为该类编写单元测试，但问题是将 NSCoder 实例传递给构造函数。我无法实例化它或将其设置为零。我如何对这个课程进行单元测试？

我想通了。被测类：

import Foundation
import UIKit

public class CustomTextField: UITextField, UITextFieldDelegate{

required public init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    self.delegate = self
}

 public func textField(textField: UITextField, shouldChangeCharactersInRange   range: NSRange, replacementString string: String) -> Bool {
    if (string == "X" ){
        //ignore input
        return false
    }
    return true
}

}

测试本身：

import UIKit
import XCTest
import TryCustom
import Foundation

class CustomTextFieldTests: XCTestCase {

  func testCustomTextField() {
    //pass in dummy non abstract NSCoder (NSKeyedUnarchiver)
    let cd = NSKeyedUnarchiver(forReadingWithData: NSMutableData())
    let c = CustomTextField(coder:cd)
    let result = c!.textField(c!, shouldChangeCharactersInRange: NSRange(), replacementString: "X")
    XCTAssertFalse(result)
  }
}