public void CompareTo_ThreePropositionsFirstBeforeSecondSecondBeforeThrid_ExpectedFirstToComeBeforeSecondAndThird()
{
// Arrange
Proposition firstInOrderproposition = new Proposition('S');
Proposition secondInOrderProposition = new Proposition('T');
Proposition thirdInOrderProposition = new Proposition('X');
// Act
// Transitive relation
int firstBeforeSecond = firstInOrderproposition.CompareTo(secondInOrderProposition);
int secondBeforeThird = secondInOrderProposition.CompareTo(thirdInOrderProposition);
int firstBeforeThrid = firstInOrderproposition.CompareTo(thirdInOrderProposition);
// Assert
firstBeforeSecond.Should().BeLessThan(SAME_POSITION, "because S comes before T");
secondBeforeThird.Should().BeLessThan(SAME_POSITION, "because T comes before X");
firstBeforeThrid.Should().BeLessThan(SAME_POSITION, "because S < T and T < X");
}
public void CompareTo_TwoPropositionsOfWhichOtherIsNull_ExpectedArgumentNullExceptionThrown()
{
// Arrange
Proposition invalidOtherProposition = null;
// Act
Action act = () => VALID_PROPOSITION.CompareTo(invalidOtherProposition);
// Assert
act.Should().Throw <ArgumentNullException>();
}
public void CompareTo_TwoPropositionsOfIdenticalVariable_ExpectedToBeEquivalent()
{
// Arrange
Proposition proposition = new Proposition('T');
Proposition otherProposition = new Proposition('T');
// Act
int samePosition = proposition.CompareTo(otherProposition);
// Assert
samePosition.Should().Be(SAME_POSITION, "because their variables are the same and thus come in the same position");
}