问题
我想为Credentials
类创建一个单元测试,验证在执行Calculate()
方法后给定凭据的密码是否等于实现IPasswordCalculator
接口的对象计算出的密码。
实际上,我创建的模拟对象在调用Calculate(ICredentials)
方法时返回string.Empty
值,而不是期望的Pa$$w0rd
。
那么...
- 我如何在不手动创建存根类的情况下实现此测试?
- 我如何定义模拟对象上的回调方法以始终返回
Pa$$w0rd
?
提前致谢。
代码
IPasswordCalculator接口
/// <summary>
/// The password calculator interface.
/// </summary>
public interface IPasswordCalculator
{
/// <summary>
/// Calculates the user password using
/// <paramref name="credentials"/> instance.
/// </summary>
/// <param name="credentials">
/// <see cref="ICredentials"/> to perform the calculation.
/// </param>
void Calculate(ICredentials credentials);
}
ICredentials interface
/// <summary>
/// The Credentials interface.
/// </summary>
public interface ICredentials
{
/// <summary>
/// Gets or sets the user password.
/// </summary>
string Password { get; set; }
/// <summary>
/// Gets the user name.
/// </summary>
string Username { get; }
/// <summary>
/// Calculates the password.
/// </summary>
void Calculate();
}
凭据实现
/// <summary>
/// User credentials.
/// </summary>
public sealed class Credentials : ICredentials
{
/// <summary>
/// Initializes a new instance of the <see cref="Credentials" /> class.
/// </summary>
/// <param name="passwordCalculator">
/// The credentials calculator.
/// </param>
/// <param name="username">
/// The user name.
/// </param>
public Credentials(IPasswordCalculator passwordCalculator, string username)
{
this.Calculator = passwordCalculator;
this.Username = username;
this.Password = string.Empty;
}
/// <summary>
/// Calculates the password.
/// </summary>
public void Calculate()
{
if (null != this.Calculator)
{
this.Calculator.Calculate(this);
}
}
}
测试
/// <summary>
/// Calculate should set password value expected using calculator.
/// </summary>
[TestMethod]
public void CalculateShouldSetPasswordValueExpectedUsingCalculator()
{
ICredentials credentials = null;
var repo = new MockRepository(MockBehavior.Default);
var mock = repo.Create<IPasswordCalculator>();
mock.Setup(x => x.Calculate(credentials))
.Callback(() => { credentials.Password = "Pa$$w0rd"; });
IPasswordCalculator calculator = mock.Object;
credentials = new Credentials(calculator, "Me");
credentials.Calculate();
Assert.AreEqual("Pa$$w0rd", credentials.Password); // Fail
}