public void InvalidInputTest()
{
// Null input
TestHelpers.AssertExceptionThrown(() => { Question1_9.IsRotation("abc", null); }, typeof(ArgumentException));
TestHelpers.AssertExceptionThrown(() => { Question1_9.IsRotation(null, "abc"); }, typeof(ArgumentException));
TestHelpers.AssertExceptionThrown(() => { Question1_9.IsRotation(null, null); }, typeof(ArgumentException));
// Empty input
TestHelpers.AssertExceptionThrown(() => { Question1_9.IsRotation("abc", string.Empty); }, typeof(ArgumentException));
TestHelpers.AssertExceptionThrown(() => { Question1_9.IsRotation(string.Empty, "abc"); }, typeof(ArgumentException));
TestHelpers.AssertExceptionThrown(() => { Question1_9.IsRotation(string.Empty, string.Empty); }, typeof(ArgumentException));
}
private static void ValidateResult(string s1, string s2, bool expectedResult)
{
Assert.AreEqual(expectedResult, Question1_9.IsRotation(s1, s2));
}