public IRunner WithTestContainerAndCase(string testContainer, string testCase)
{
if (IsSpecified(testCase, AllTestCases) && !IsSpecified(testContainer, AllTestContainers))
throw new ArgumentException("A test container must be specified if a test case is specified.", "testContainer");
_testContainer = Normalize(testContainer, AllTestContainers);
_testCase = Normalize(testCase, AllTestCases);
return this;
}