public int GetLetterCountRecursive_ParametersAreValid_ReturnsCharsCount(string str)
{
// Act
return(DoWhileMethods.GetLetterCountRecursive(str));
}
public void GetLetterCountRecursive_StrIsNull_ThrowsException()
{
// Act
Assert.Throws <ArgumentNullException>(() => DoWhileMethods.GetLetterCountRecursive(null));
}