NUnit: TestCaseSource assigns tests to specific test methods

Question

I'm planning to store all test cases in a excel file with columns indicate test method names, parameters and expected results; however, I found TestCaseSource simply assigns all test cases to every test method. I'm wondering that is there any way I can make NUnit select test cases for methods base on method names I put in the spreadsheet?

Thanks.

Answer 1

There is a way to do this. For example, as you mentioned, you can create a custom attribute.
The idea is to pass name of test to TestCaseSource.
You can do it by creating TestCaseSource as separate class.

First, TestCaseSource class:

public class SpreadSheetTestCaseSource
{
    [ThreadStatic] 
    public static string TestName = String.Empty;

    public static IEnumerable TestCases
    {
        get
        {
            SpreadSheetTestCaseProvider.GetTestCases()
                 .Where(testCase => testCase.TestName == TestName);
        }
    }
}

Then attribute:

public class MyTestCaseSourceAttribute : TestCaseSourceAttribute
{
    public MyTestCaseSourceAttribute(Type sourceType, string sourceName, 
        [CallerMemberName] string name = null)
        : base(sourceType, sourceName)
    {
        SpreadSheetTestCaseSource.TestName = name;
    }

    //Another two members impl.
}

And test:

[TestFixture]
public class TestClass
{
    [MyTestCaseSource(typeof(SpreadSheetTestCaseSource), "TestCases")]
    public void TestMethod()
    {
        //Test logic
    }
}

SpeadSheetTestCaseSource.TestName is thread static. So you can run tests parallel.