public void ForwardThenInverseShiftProducesSimilarTextWithUnknownLetters()
{
var plaintext = "this is a secret message";
var shifter = new CaesarShifter();
var shiftedText = shifter.Shift(plaintext, LetterSet.LowerCaseLatin, 3);
var unshiftedText = shifter.Shift(shiftedText, LetterSet.LowerCaseLatin, 23);
Assert.AreEqual(plaintext, unshiftedText);
}
public void ShiftByNegativeNumberShiftsViaMoulus()
{
var plaintext = "this is a secret message";
var expected = "wklv lv d vhfuhw phvvdjh";
var shifter = new CaesarShifter();
var shiftedText = shifter.Shift(plaintext, LetterSet.LowerCaseLatin, -23);
Assert.AreEqual(expected, shiftedText);
}
public void ShiftWithUnkownCharactersLeavesThemInvariant()
{
var plaintext = "this is a secret message.";
var expected = "wklv lv d vhfuhw phvvdjh.";
var shifter = new CaesarShifter();
var shiftedText = shifter.Shift(plaintext, LetterSet.LowerCaseLatin, 3);
Assert.AreEqual(expected, shiftedText);
}
public void WellKnownCaesarShiftProducesWellKnownResult()
{
var plaintext = "this is a secret message";
var expected = "wklv lv d vhfuhw phvvdjh";
var shifter = new CaesarShifter();
var shiftedText = shifter.Shift(plaintext, LetterSet.LowerCaseLatin, 3);
Assert.AreEqual(expected, shiftedText);
}