如何使用Moq模拟返回值为(bool, string)的异步方法？

要模拟返回Task<(bool, string)>类型的方法，只需向ReturnsAsync传入对应的值元组即可，具体写法如下：

直接传入元组字面量 #

这是最简洁的写法，适合简单场景：

var mockInsuranceService = new Mock<IInsuranceService>();
mockInsuranceService
    .Setup(x => x.CreatePhoneCertificate(12345, It.IsAny<CancellationToken>()))
    .ReturnsAsync((true, "证书创建成功"));

先声明元组变量再传入 #

如果需要复用元组结果或逻辑更复杂，可以先定义元组变量：

// 定义模拟结果元组
var mockCertificateResult = (IsSuccess: true, Message: "证书创建成功");

var mockInsuranceService = new Mock<IInsuranceService>();
mockInsuranceService
    .Setup(x => x.CreatePhoneCertificate(12345, It.IsAny<CancellationToken>()))
    .ReturnsAsync(mockCertificateResult);

模拟失败场景 #

只需修改元组的布尔值和提示字符串即可：

var mockInsuranceService = new Mock<IInsuranceService>();
mockInsuranceService
    .Setup(x => x.CreatePhoneCertificate(12345, It.IsAny<CancellationToken>()))
    .ReturnsAsync((false, "订单不存在，无法创建证书"));

内容的提问来源于stack exchange，提问作者M Javad Salehi