public void TestMixedOptionalAndNonOptionalArgumentsThrows()
{
AssertInvalidArgumentCount("$test IamACommand x y z", "Mixed validators (optional/non-optional) are not supported. Validators should follow the order: no, no, ..., op, op, ... op",
a1 => JiraParamValidator.IssueId,
a2 => JiraParamValidator.IssueId.AsOptional(),
a3 => JiraParamValidator.IssueId);
}