如何测试IActionResult及其内容

Question

我正在使用C#和.NET Core2.0开发一个ASP.NET Core2 web api。

我更改了一个方法，将它添加到try-catch中，以允许我返回状态代码。

public IEnumerable<GS1AIPresentation> Get()
{
    return _context
        .GS1AI
        .Select(g => _mapper.CreatePresentation(g))
        .ToList();
}

更改为：

public IActionResult Get()
{
    try
    {
        return Ok(_context
            .GS1AI
            .Select(g => _mapper.CreatePresentation(g))
            .ToList());
    }
    catch (Exception)
    {
        return StatusCode(500);
    }
}

但是现在我在测试方法中遇到了一个问题，因为它现在返回一个IActionResult而不是IEnumerable<GS1AIPresentation>

[Test]
public void ShouldReturnGS1Available()
{
    // Arrange
    MockGS1(mockContext, gs1Data);

    GS1AIController controller =
        new GS1AIController(mockContext.Object, mockMapper.Object);

    // Act
    IEnumerable<Models.GS1AIPresentation> presentations = controller.Get();

    // Arrange
    Assert.AreEqual(presentations.Select(g => g.Id).Intersect(gs1Data.Select(d => d.Id)).Count(),
                    presentations.Count());
}

我的问题在这里：IEnumerable<Models.GS1AIPresentation> presentations = controller.Get();。

我是否需要重构并创建一个新方法来测试Select

此选择：

return _context
    .GS1AI
    .Select(g => _mapper.CreatePresentation(g))
    .ToList();

或者我可以在IActionResult中获取IEnumerable<Models.GS1AIPresentation>

Answer 1

控制器中调用的return Ok(...)将返回一个OkObjectResult，它派生自IActionResult，因此您需要强制转换为该类型，然后访问其中的值。

[Test]
public void ShouldReturnGS1Available() {
    // Arrange
    MockGS1(mockContext, gs1Data);

    var controller = new GS1AIController(mockContext.Object, mockMapper.Object);

    // Act
    IActionResult result = controller.Get();        

    // Assert
    var okObjectResult = result as OkObjectResult;
    Assert.IsNotNull(okObjectResult);
    var presentations = okObjectResult.Value as IEnumerable<Models.GS1AIPresentation>;
    Assert.IsNotNull(presentations);
    Assert.AreEqual(presentations.Select(g => g.Id).Intersect(gs1Data.Select(d => d.Id)).Count(),
                    presentations.Count());
}

参考Asp.Net Core Action Results Explained