public static Sequence<Sequence<CompoundTerm>> GenerateTestSequences(FSM fa)
{
//Eliminate dead states from the fa
Set<Term> deadStates = GetDeadStates(fa);
Set<Term> aliveStates = fa.States.Difference(deadStates);
Set<Triple<Term, CompoundTerm, Term>> aliveTransitions =
fa.Transitions.Select(delegate(Triple<Term, CompoundTerm, Term> trans)
{
return aliveStates.Contains(trans.First) &&
aliveStates.Contains(trans.Third);
});
if (aliveTransitions.IsEmpty) //test suite cannot be generated
return Sequence<Sequence<CompoundTerm>>.EmptySequence;
//Build a graph from the alive transitions
Term[] states = new Term[aliveStates.Count];
Dictionary<Term, int> stateToVertexMap = new Dictionary<Term, int>();
states[0] = fa.InitialState;
stateToVertexMap[fa.InitialState] = 0;
int i = 1;
foreach (Term state in aliveStates.Remove(fa.InitialState))
{
states[i] = state;
stateToVertexMap[state] = i++;
}
//create edges that must be traversed
GraphTraversals.Edge[] mustEdges = new GraphTraversals.Edge[aliveTransitions.Count];
Triple<Term, CompoundTerm, Term>[] mustTransitions = new Triple<Term, CompoundTerm, Term>[aliveTransitions.Count];
i = 0;
foreach (Triple<Term, CompoundTerm, Term> trans in aliveTransitions)
{
GraphTraversals.Edge edge = new GraphTraversals.Edge(stateToVertexMap[trans.First],
stateToVertexMap[trans.Third], i);
mustEdges[i] = edge;
mustTransitions[i++] = trans;
}
//add an optional edge with label -1 from every accepting state
//to the initial state, this corresponds to a reset action
GraphTraversals.Edge[] optionalEdges =
new GraphTraversals.Edge[fa.AcceptingStates.Count];
i = 0;
foreach (Term accState in fa.AcceptingStates)
{
int accVertex = stateToVertexMap[accState];
optionalEdges[i++] = new GraphTraversals.Edge(accVertex, 0, -1); //-1 = reset
}
//at this point it is known that g is strongly connected and has no dead states
//so a postman tour exists, compute a postman tour
GraphTraversals.Graph g =
new GraphTraversals.Graph(0, mustEdges, optionalEdges,
GraphTraversals.WeakClosureEnum.DoNotClose);
List<GraphTraversals.Edge> postmanTour =
new List<GraphTraversals.Edge>(g.GetRuralChinesePostmanTour());
#region normalize the tour so that it ends in an accepting state and has a reset at the end as a "watchdog"
//if the last edge has not label -1, i.e. the edge leading back
//to the initial state is not a reset edge from an accepting state
//and the last state is not an accepting state
//then extend the path to an accepting state, from the beginning of the path
//notice that there must be at least one accepting state, so such an extesion
//is indeed possible
GraphTraversals.Edge lastEdge = postmanTour[postmanTour.Count - 1];
if (lastEdge.label >= 0) //if the last edge is a reset, we are done
{
//the last edge leads back to the initial state, because this is a tour
if (fa.AcceptingStates.Contains(fa.InitialState))
postmanTour.Add(new GraphTraversals.Edge(0, 0, -1)); //add a watchdog
else
{
//create an extesion to the tour from the initial state to the first accepting state
List<GraphTraversals.Edge> extension = new List<GraphTraversals.Edge>();
foreach (GraphTraversals.Edge edge in postmanTour)
{
extension.Add(edge);
if (fa.AcceptingStates.Contains(states[edge.target]))
{
//the end state of the edge is accepting, so we are done
extension.Add(new GraphTraversals.Edge(0, 0, -1)); //add a watchdog
break;
}
}
postmanTour.AddRange(extension);
}
}
#endregion
#region break up the tour into sequences of transition ids separated by the reset edge
List<List<int>> paths = new List<List<int>>();
List<int> path = new List<int>();
for (int k = 0; k < postmanTour.Count; k++)
{
//presense of the watchdog at the end of the tour is assumed here
GraphTraversals.Edge edge = postmanTour[k];
if (edge.label < 0) //encountered reset, end of path
{
paths.Add(path);
path = new List<int>();
}
else
{
path.Add(edge.label);
}
}
#endregion
#region map the paths into action sequences
Sequence<Sequence<CompoundTerm>> res = Sequence<Sequence<CompoundTerm>>.EmptySequence;
foreach (List<int> path1 in paths)
{
Sequence<CompoundTerm> transSeq = Sequence<CompoundTerm>.EmptySequence;
foreach (int transId in path1)
transSeq = transSeq.AddLast(mustTransitions[transId].Second);
res = res.AddLast(transSeq);
}
#endregion
return res;
}
public static Sequence <Sequence <CompoundTerm> > GenerateTestSequences(FSM fa)
{
//Eliminate dead states from the fa
Set <Term> deadStates = GetDeadStates(fa);
Set <Term> aliveStates = fa.States.Difference(deadStates);
Set <Triple <Term, CompoundTerm, Term> > aliveTransitions =
fa.Transitions.Select(delegate(Triple <Term, CompoundTerm, Term> trans)
{
return(aliveStates.Contains(trans.First) &&
aliveStates.Contains(trans.Third));
});
if (aliveTransitions.IsEmpty) //test suite cannot be generated
{
return(Sequence <Sequence <CompoundTerm> > .EmptySequence);
}
//Build a graph from the alive transitions
Term[] states = new Term[aliveStates.Count];
Dictionary <Term, int> stateToVertexMap = new Dictionary <Term, int>();
states[0] = fa.InitialState;
stateToVertexMap[fa.InitialState] = 0;
int i = 1;
foreach (Term state in aliveStates.Remove(fa.InitialState))
{
states[i] = state;
stateToVertexMap[state] = i++;
}
//create edges that must be traversed
GraphTraversals.Edge[] mustEdges = new GraphTraversals.Edge[aliveTransitions.Count];
Triple <Term, CompoundTerm, Term>[] mustTransitions = new Triple <Term, CompoundTerm, Term> [aliveTransitions.Count];
i = 0;
foreach (Triple <Term, CompoundTerm, Term> trans in aliveTransitions)
{
GraphTraversals.Edge edge = new GraphTraversals.Edge(stateToVertexMap[trans.First],
stateToVertexMap[trans.Third], i);
mustEdges[i] = edge;
mustTransitions[i++] = trans;
}
//add an optional edge with label -1 from every accepting state
//to the initial state, this corresponds to a reset action
GraphTraversals.Edge[] optionalEdges =
new GraphTraversals.Edge[fa.AcceptingStates.Count];
i = 0;
foreach (Term accState in fa.AcceptingStates)
{
int accVertex = stateToVertexMap[accState];
optionalEdges[i++] = new GraphTraversals.Edge(accVertex, 0, -1); //-1 = reset
}
//at this point it is known that g is strongly connected and has no dead states
//so a postman tour exists, compute a postman tour
GraphTraversals.Graph g =
new GraphTraversals.Graph(0, mustEdges, optionalEdges,
GraphTraversals.WeakClosureEnum.DoNotClose);
List <GraphTraversals.Edge> postmanTour =
new List <GraphTraversals.Edge>(g.GetRuralChinesePostmanTour());
#region normalize the tour so that it ends in an accepting state and has a reset at the end as a "watchdog"
//if the last edge has not label -1, i.e. the edge leading back
//to the initial state is not a reset edge from an accepting state
//and the last state is not an accepting state
//then extend the path to an accepting state, from the beginning of the path
//notice that there must be at least one accepting state, so such an extesion
//is indeed possible
GraphTraversals.Edge lastEdge = postmanTour[postmanTour.Count - 1];
if (lastEdge.label >= 0) //if the last edge is a reset, we are done
{
//the last edge leads back to the initial state, because this is a tour
if (fa.AcceptingStates.Contains(fa.InitialState))
{
postmanTour.Add(new GraphTraversals.Edge(0, 0, -1)); //add a watchdog
}
else
{
//create an extesion to the tour from the initial state to the first accepting state
List <GraphTraversals.Edge> extension = new List <GraphTraversals.Edge>();
foreach (GraphTraversals.Edge edge in postmanTour)
{
extension.Add(edge);
if (fa.AcceptingStates.Contains(states[edge.target]))
{
//the end state of the edge is accepting, so we are done
extension.Add(new GraphTraversals.Edge(0, 0, -1)); //add a watchdog
break;
}
}
postmanTour.AddRange(extension);
}
}
#endregion
#region break up the tour into sequences of transition ids separated by the reset edge
List <List <int> > paths = new List <List <int> >();
List <int> path = new List <int>();
for (int k = 0; k < postmanTour.Count; k++)
{
//presense of the watchdog at the end of the tour is assumed here
GraphTraversals.Edge edge = postmanTour[k];
if (edge.label < 0) //encountered reset, end of path
{
paths.Add(path);
path = new List <int>();
}
else
{
path.Add(edge.label);
}
}
#endregion
#region map the paths into action sequences
Sequence <Sequence <CompoundTerm> > res = Sequence <Sequence <CompoundTerm> > .EmptySequence;
foreach (List <int> path1 in paths)
{
Sequence <CompoundTerm> transSeq = Sequence <CompoundTerm> .EmptySequence;
foreach (int transId in path1)
{
transSeq = transSeq.AddLast(mustTransitions[transId].Second);
}
res = res.AddLast(transSeq);
}
#endregion
return(res);
}
