使用 XUnit 将一个测试拆分为多个测试 - 避免 for 循环

Question

I have seen quite a bunch of threads showing how to pass data sets as input arguments to an XUnit test, but examples always have pretty limited amount of combinations to execute.
What if you were to run a test with N x M combinations?
An easy way to do it would be to write one test, taking no input argument and simply execute all combinations of the test using a loop in a loop.
This approach is however not desired as it become impossible (without hacks) to dissociate the failing tests from the passing ones. It either all passes or all fails.

Here is a bit of a sketch of the type of test using loops that I would like to avoid and therefore convert:

[Fact]
public void NumberOfBytesPerBlockCannotExceedLimit()
{
    // Test setup
    ....

    // Repeat test for different number of bytes per word
    int[] bytesPerWordArray = new int[5] { 1, 3, 4, 6, 8, ... };
    foreach (int bytesPerWord in bytesPerWordArray)
    {
        // Repeat test N times, for different amount of reserved bytes
        int[] numReservedBytesArray= new int[5] { 1, 2, 3, 4, ... }; 
        foreach (int numReservedBytes in numReservedBytesArray)
        {
            // The actual test
            ...
        }
    }
}

Now, how do I split this test without having to type every combination/vector one by one in an inline or a IEnumerable/MemberData?
Ideally, both bytesPerWordArray and numReservedBytesArray should be turned into some sorts of input vector!?

Answer 1

Here's an example how to do it using MemberData :

[Theory]
[MemberData(nameof(TestData))]
public void Test(int test1, int test2, int expected)
{
    var result = test1 + test2;
    Assert.Equal(expected, result);
}

public static IEnumerable<object[]> TestData()
{
    for (var i = 0; i < 5; i++)
    {
        for (var j = 0; j < 5; j++)
        {
            yield return new object[] { i, j, i + j };
        }
    }
}