Remove Graph.ReverseEdges by merging with Graph.Edges.

godip.go

@@ -277,8 +277,7 @@ type Graph interface {
 	SC(Province) *Nation
 	Path(src, dst Province, reverse bool, filter PathFilter) []Province
 	Coasts(Province) []Province
-	Edges(src Province) map[Province]map[Flag]bool
-	ReverseEdges(src Province) map[Province]map[Flag]bool
+	Edges(src Province, reverse bool) map[Province]map[Flag]bool
 	SCs(Nation) []Province
 	AllSCs() []Province
 	Provinces() []Province

graph/graph.go

@@ -83,17 +83,11 @@ func (self *Graph) AllSCs() (result []godip.Province) {
 	return
 }
 
-func (self *Graph) Edges(n godip.Province) (result map[godip.Province]map[godip.Flag]bool) {
+// Edges returns the edges leading away from the specified province, or if reverse
+// is set to true then it instead returns the edges leading to it.
+func (self *Graph) Edges(n godip.Province, reverse bool) (result map[godip.Province]map[godip.Flag]bool) {
 	result = map[godip.Province]map[godip.Flag]bool{}
-	for p, edge := range self.edges(n, false) {
-		result[p] = edge.Flags
-	}
-	return
-}
-
-func (self *Graph) ReverseEdges(n godip.Province) (result map[godip.Province]map[godip.Flag]bool) {
-	result = map[godip.Province]map[godip.Flag]bool{}
-	for p, edge := range self.edges(n, true) {
+	for p, edge := range self.edges(n, reverse) {
 		result[p] = edge.Flags
 	}
 	return

orders/move.go

@@ -367,9 +367,9 @@ func MoveSupport(r godip.Resolver, src, dst godip.Province, forbiddenSupports []
 
 func HasEdge(v godip.Validator, typ godip.UnitType, src, dst godip.Province) bool {
 	if typ == godip.Army {
-		return v.Graph().Flags(dst)[godip.Land] && v.Graph().Edges(src)[dst][godip.Land]
+		return v.Graph().Flags(dst)[godip.Land] && v.Graph().Edges(src, false)[dst][godip.Land]
 	} else {
-		return v.Graph().Flags(dst)[godip.Sea] && v.Graph().Edges(src)[dst][godip.Sea]
+		return v.Graph().Flags(dst)[godip.Sea] && v.Graph().Edges(src, false)[dst][godip.Sea]
 	}
 }
 
@@ -384,10 +384,7 @@ func PossibleMovesUnit(v godip.Validator, unitType godip.UnitType, start godip.P
 		noConvoyStr = string(*noConvoy)
 	}
 	return v.MemoizeProvSlice(fmt.Sprintf("PossibleMovesUnit(%v,%v,%v,%v,%v)", unitType, start, reverse, allowConvoy, noConvoyStr), func() []godip.Province {
-		neighbours := v.Graph().Edges(start)
-		if reverse {
-			neighbours = v.Graph().ReverseEdges(start)
-		}
+		neighbours := v.Graph().Edges(start, reverse)
 		ends := map[godip.Province]bool{}
 		if unitType == godip.Army {
 			for end, flags := range neighbours {
@@ -472,7 +469,7 @@ func movePossible(v godip.Validator, typ godip.UnitType, src, dst godip.Province
 			return godip.ErrIllegalDestination
 		}
 		if !allowConvoy {
-			flags, found := v.Graph().Edges(src)[dst]
+			flags, found := v.Graph().Edges(src, false)[dst]
 			if !found {
 				return godip.ErrIllegalMove
 			}

phase/phase.go

@@ -186,7 +186,7 @@ func (self *Phase) PostProcess(s godip.State) (err error) {
 	} else if self.Ty == godip.Movement {
 		for prov, unit := range s.Dislodgeds() {
 			hasRetreat := false
-			for edge, _ := range s.Graph().Edges(prov) {
+			for edge, _ := range s.Graph().Edges(prov, false) {
 				if _, _, ok := s.Unit(edge); !ok && !s.Bounce(prov, edge) {
 					if orders.HasEdge(s, unit.Type, prov, edge) {
 						godip.Logf("%v can retreat to %v", prov, edge)