单元测试

public class AliyunSmsServiceTests
{
    private readonly HttpTestHelper _http = new();

    [Fact]
    public async Task SendAsync_Success_Returns_Ok_Result()
    {
        // ① Arrange——配置 Mock 响应
        _http.RespondWith("""
            {"Code":"OK","RequestId":"req-123","BizId":"biz-456"}
            """);

        var options = new AliyunSmsOptions
        {
            AccessKeyId = "test-key",
            AccessKeySecret = "test-secret",
            SignName = "Bitzsoft",
        };

        var services = new ServiceCollection();
        services.AddAliyunSms(o =>
        {
            o.AccessKeyId = options.AccessKeyId;
            o.AccessKeySecret = options.AccessKeySecret;
            o.SignName = options.SignName;
        });
        // ② 替换 HttpClient 为 Mock
        services.AddHttpClient<AliyunSmsService>()
            .ConfigurePrimaryHttpMessageHandler(() => _http.Handler);

        var sp = services.BuildServiceProvider();
        var sms = sp.GetRequiredService<ISMS>();

        // ③ Act
        var result = await sms.SendAsync(new SmsMessage
        {
            To = "13800138000",
            TemplateId = "SMS_123",
            TemplateParams = new() { ["code"] = "123456" },
        });

        // ④ Assert——Result 模式的断言
        result.Success.Should().BeTrue();
        result.RequestId.Should().Be("req-123");
        result.BizId.Should().Be("biz-456");
    }

    [Fact]
    public async Task SendAsync_Provider_Error_Returns_Fail_Result()
    {
        // ① 模拟厂商返回业务错误
        _http.RespondWith("""
            {"Code":"isv.BUSINESS_LIMIT_CONTROL","Message":"业务限流"}
            """);

        // ... 注册和获取 service ...

        var result = await sms.SendAsync(message);

        // ② 断言失败结果的结构化错误码
        result.Success.Should().BeFalse();
        result.ErrorCode.Should().Be("isv.BUSINESS_LIMIT_CONTROL");
        result.ErrorMessage.Should().Contain("业务限流");
    }

    [Fact]
    public async Task SendAsync_Network_Error_Returns_Exception_Result()
    {
        // ① 模拟网络异常
        _http.Throw(new HttpRequestException("Connection refused"));

        var result = await sms.SendAsync(message);

        // ② 网络错误被捕获并转换为失败 Result
        result.Success.Should().BeFalse();
        result.ErrorCode.Should().Be("EXCEPTION");
    }
}

public class HttpTestHelper : IDisposable
{
    public HttpMessageHandlerMock Handler { get; } = new();
    public void RespondWith(string json, int statusCode = 200) { ... }
    public void Throw(Exception ex) { ... }
    public void Dispose() => Handler.Dispose();
}