TestCases 如何测试抛出不同的异常？

Question

我是 TestCases 的忠实粉丝，因为它们使测试更多边缘案例变得微不足道，而且反测试者似乎更愿意使用更少的测试代码行。不过，我一直在为异常测试而苦苦挣扎。

在我的代码中，我有一个验证函数，用于检查配置中是否有 1 个且只有 1 个实例。如果有 0 个，我抛出一个 KeyNotFoundException，如果有超过 1 个，我抛出一个 AmbiguousMatchException。

private void ThrowIfNotInConfig(string endpointRef)
{
    var count = _config.Endpoints?.Count(x => x.Ref.Equals(endpointRef)) ?? 0;
    if (count == 0)
    {
        throw new KeyNotFoundException($"{nameof(ThrowIfNotInConfig)} - " +
                                       $"No Endpoint in appSettings with the ref {endpointRef}");
    }
    if (count > 1)
    {
        throw new AmbiguousMatchException($"{nameof(ThrowIfNotInConfig)} - " +
                                      $"More than 1 Endpoint in appSettings with the ref {endpointRef}");
    }
}

有没有一种方法可以避免将它们分成 2 个单独的测试，只是因为异常类型，这比这更整洁？我不喜欢在测试中做 try catch，我觉得应该有一种方法来测试异常，就像 ExpectedException 过去那样。

[TestCase(0, ExpectedResult = "KeyNotFoundException")]
[TestCase(2, ExpectedResult = "AmbiguousMatchException")]
public string ThrowIfNotInConfig_GIVEN_NotASingleEndpointInConfig_THEN_ThrowError(int configOccurrences)
{
    // Arrange
    const string endpointRef = "ABC";
    var config = _validConfig;
    config.Endpoints.RemoveAll(x => x.Ref == endpointRef);
    config.Endpoints
        .AddRange(Enumerable.Range(0, configOccurrences)
            .Select(x => new MiraklEndpointConfig { Ref = endpointRef })
        );
    _config.Setup(c => c.Value).Returns(config);

    var service = new URLThrottlingService(_mockLogger.Object, _config.Object);
    
    try
    {
        // Act
        service.IsOKToCallEndpoint(endpointRef);
    }
    catch (Exception exception)
    {
        return exception.GetType().Name;
    }

    return "";
}

Answer 1

感谢canton7 and ，我现在有了这个，这就是我想要的

[TestCase(0, typeof(KeyNotFoundException))]
[TestCase(2, typeof(AmbiguousMatchException))]
public void ThrowIfNotInConfig_GIVEN_NotASingleEndpointInConfig_THEN_ThrowError(int configOccurrences, Type exception)
{
    // Arrange
    const string endpointRef = "ABC";
    var config = _validConfig;
    config.Endpoints.RemoveAll(x => x.Ref == endpointRef);
    config.Endpoints
        .AddRange(Enumerable.Range(0, configOccurrences)
            .Select(x => new MiraklEndpointConfig { Ref = endpointRef })
        );
    _config.Setup(c => c.Value).Returns(config);

    var service = new URLThrottlingService(_mockLogger.Object, _config.Object);

    // Act / Assert
    Assert.Throws(exception, () => service.IsOKToCallEndpoint(endpointRef));
}

TestCases 如何测试抛出不同的异常？

How can TestCases test different exceptions are thrown?

c#

unit-testing

.net-core

nunit