public void CheckCharacterLimit_UnderLimit()
{
const int characterLimit = 5;
var word = string.Empty;
for (int i = 0; i < characterLimit - 1; i++)
{
word += "a";
}
//arrange
_appSettings.Setup(x => x.CharacterLimit).Returns(characterLimit);
//act
var result = _mainHelper.CheckCharacterLimit(word);
//assert
AssertWithMessage.AreEqual(result, true, "character limit");
}