AssetSpawnerTest_Step3.cs

 public class AssetSpawnerTest 
{
    [UnityTest]
    public IEnumerator Should_InstantiateObject_When_GivenStringHasNameAndPosition()
    {
        //given 
        String csvString = "CubeX,2,3,3";
        String expectedName = "CubeX";
        //when
        AssetSpawner assetSpawner = new AssetSpawner();
        assetSpawner.createAGameObjectFromString(csvString);
        //then
        Assert.IsNotNull(GameObject.Find(expectedName));
        yield return null;
    }
}