在拆解中未通过NUnit测试

Question

I have a bunch of automated UI tests running with selenium and NUnit.

After every nunit test I want to check the browser for any JS errors that have occurred. If there are any JS errors the test that caused them should fail. I want this to run for all tests I write without having to copy the check into each test.

I also take screenshots on any failure.

    [TearDown]
    public void TearDown()
    {
        Assert.Fail("Some JS error occurred"); //This is to simulate a JS error assertion

        if (TestContext.CurrentContext.Result.Status != TestStatus.Passed)
        {
            Driver.TakeScreenshot(TestContext.CurrentContext.Test.Name, "Failed");
        }
    }

If I fail an assertion inside teardown it will never execute the screenshot code (as the assert is an exception).

Is there a better way to fail the test here so that I can carry on with my logic?

Answer 1

You could extend your own TestActionAttribute that runs your JS tests. If an assertion failure is thrown in AfterTest() , NUnit seems to report the test as being failed.

Eg this:

[CheckForJSErrors] // your custom attribute - applies to all tests
public class ClassTest
{
    [Test]
    public void MyTest()
    {
        // Your test case
    }
}

[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class)]
public class CheckForJSErrorsAttribute : TestActionAttribute
{
    public override void AfterTest(TestDetails testDetails)
    {
        // if you only want to check for JS errors if the test passed, then:
        if(TestContext.CurrentContext.Result.Status == TestStatus.Passed)
        {
            Driver.TakeScreenshot(testDetails.FullName, "Failed");
            Assert.Fail("Some JS error occurred"); //This is to simulate a JS error assertion
        }
    }
    public override ActionTargets Targets
    {
        // explicitly says to run this after each test, even if attr is defined on the entire test fixture
        get { return ActionTargets.Test; }
    }
}

Produces this failure in NUnit:

SO_34306757.ClassTest.MyTest: TearDown : NUnit.Framework.AssertionException : Some JS error occurred

I've declared the [CheckForJSErrors] attribute for the entire test fixture to avoid having to declare it on every test case, but you could declare it per test method if you want.

Answer 2

If you want to check the same thing after every test, you could just right a common method that you call in each test itself. That way you're not duplicating the test code and you are keeping the fail assert out of the tear down.

Eg.

[Test]
public void Test1()
{
    // sometest code
    TestJS();
}

[Test]
public void Test2()
{
    // some other test code
    TestJS();
}

public void TestJS()
{
    Assert.Fail("Or whatever to test the JS");
}

[TearDown]
public void TearDown()
{
    if (TestContext.CurrentContext.Result.Status != TestStatus.Passed)
    {
        Driver.TakeScreenshot(TestContext.CurrentContext.Test.Name, "Failed");
    }
}