public void IsReplaced_ReplacingExistingBoundVariableInBinaryConnectiveComposedOfPredicates_BothChildrenShouldReturnTrue(char connectiveSymbol)
{
// Arrange
char existingVariable = 'y';
List <char> variables = new List <char>()
{
existingVariable
};
Predicate leftPredicate = new Predicate(PREDICATE_SYMBOL, variables);
Predicate rightPredicate = new Predicate('Q', variables);
BinaryConnective binaryConnective = PropositionGenerator.CreateBinaryConnectiveWithRandomSymbols(connectiveSymbol);
binaryConnective.LeftSuccessor = leftPredicate;
binaryConnective.RightSuccessor = rightPredicate;
char replacementVariable = 'c';
// Act
binaryConnective.Replace(existingVariable, replacementVariable);
bool leftIsReplaced = leftPredicate.IsReplaced(existingVariable);
bool rightIsReplaced = rightPredicate.IsReplaced(existingVariable);
// Assert
leftIsReplaced.Should().BeTrue($"Since the bound variable {existingVariable} should be repalced replaced by {replacementVariable}");
rightIsReplaced.Should().BeTrue($"Since the bound variable {existingVariable} should be repalced replaced by {replacementVariable}");
}
public virtual void GetBoundVariables_CalledOnABinaryConnective_ExpectedNotImplementedExceptionThrown()
{
// Arrange
BinaryConnective binaryConnective = createBinaryConnective();
Action act = () => binaryConnective.GetBoundVariables();
// Act // Assert
act.Should().Throw <NotImplementedException>("Because it is not clear what should happen when calling this on a binary connective");
}
public BinaryPredicate(BinaryConnective connective, Predicate first, Predicate second)
{
Debug.Assert(connective != null);
Debug.Assert(first != null);
Debug.Assert(second != null);
this.connective = connective;
this.first = first;
this.second = second;
}
private void AddChildrenToStack(ref Stack <Proposition> propositionStack, Proposition proposition)
{
if (proposition is UnaryConnective)
{
UnaryConnective unaryConnective = (UnaryConnective)proposition;
propositionStack.Push(unaryConnective.LeftSuccessor);
}
if (proposition is BinaryConnective)
{
BinaryConnective binaryConnective = (BinaryConnective)proposition;
propositionStack.Push(binaryConnective.RightSuccessor);
}
}
private static void addChildren(BinaryConnective binaryConnective, List <Proposition> queue)
{
Proposition leftSuccessor = binaryConnective.LeftSuccessor;
Proposition rightSuccessor = binaryConnective.RightSuccessor;
if (leftSuccessor != null)
{
queue.Add(leftSuccessor);
}
if (rightSuccessor != null)
{
queue.Add(rightSuccessor);
}
}
public void CreateDisjunctiveNormalForm_ExpressionGiven_ExpectedPropositionLiteralsAtTheLeavesAndNoDisjunctionDeeperThanConjunction(char expressionSymbol)
{
// For the binary connectives, we should check all (both) possible branches if they contain
// no disjunction below a conjunction
// Arrange
BinaryConnective root = PropositionGenerator.CreateBinaryConnectiveWithRandomSymbols(expressionSymbol);
TruthTable tt = new TruthTable(root);
TruthTable simplifiedTt = tt.Simplify();
// Act
Proposition dnf = tt.CreateDisjunctiveNormalForm();
Proposition simplifiedDnf = simplifiedTt.CreateDisjunctiveNormalForm();
// Assert
Assert.True(IsInDnf(dnf), "Because this expression should be in DNF");
Assert.True(IsInDnf(simplifiedDnf), "Because the simplified expression should also be in DNF");
}
protected void Copy_CopyingBinaryConnectiveWithTwoRandomVariableSymbols_ExpectedDifferentReferencesForConnective(BinaryConnective originalConenctive)
{
// Act
Proposition copy = originalConenctive.Copy();
bool sameReference = originalConenctive == copy;
// Assert
originalConenctive.Equals(copy).Should().BeTrue("Because all the data should be equal");
sameReference.Should().BeFalse("Because a copy should be a different object reference");
}
protected void Calculate_DetermineAllPossibleValuesBetweenTwoPropositionVariables(BinaryConnective connective, string message, bool left, bool right, bool expected)
{
// Arrange
connective.LeftSuccessor.TruthValue = left;
connective.RightSuccessor.TruthValue = right;
// Act
bool actualTruthValue = connective.Calculate();
// Assert
actualTruthValue.Should().Be(expected, message);
}
