Fix incorrect handling of timetable operations on counter and release slot orders

See: #485

src/order_base.h

@@ -423,10 +423,21 @@ public:
 	 * autofilled we can be sure that any non-zero values for their wait_time and travel_time are
 	 * explicitly set (but travel_time is actually unused for conditionals). */
 
+	/* Does this order not have any associated travel or wait times */
+	inline bool HasNoTimetableTimes() const { return this->IsType(OT_COUNTER) || this->IsType(OT_RELEASE_SLOT); }
+
 	/** Does this order have an explicit wait time set? */
-	inline bool IsWaitTimetabled() const { return this->IsType(OT_CONDITIONAL) ? HasBit(this->GetXFlags(), 0) : HasBit(this->flags, 3); }
+	inline bool IsWaitTimetabled() const
+	{
+		if (this->HasNoTimetableTimes()) return true;
+		return this->IsType(OT_CONDITIONAL) ? HasBit(this->GetXFlags(), 0) : HasBit(this->flags, 3);
+	}
 	/** Does this order have an explicit travel time set? */
-	inline bool IsTravelTimetabled() const { return this->IsType(OT_CONDITIONAL) ? this->travel_time > 0 : HasBit(this->flags, 7); }
+	inline bool IsTravelTimetabled() const
+	{
+		if (this->HasNoTimetableTimes()) return true;
+		return this->IsType(OT_CONDITIONAL) ? this->travel_time > 0 : HasBit(this->flags, 7);
+	}
 
 	/** Get the time in ticks a vehicle should wait at the destination or 0 if it's not timetabled. */
 	inline TimetableTicks GetTimetabledWait() const { return this->IsWaitTimetabled() ? this->wait_time : 0; }
@@ -447,6 +458,7 @@ public:
 	/** Set if the wait time is explicitly timetabled (unless the order is conditional). */
 	inline void SetWaitTimetabled(bool timetabled)
 	{
+		if (this->HasNoTimetableTimes()) return;
 		if (this->IsType(OT_CONDITIONAL)) {
 			SB(this->GetXFlagsRef(), 0, 1, timetabled ? 1 : 0);
 		} else {
@@ -455,7 +467,10 @@ public:
 	}
 
 	/** Set if the travel time is explicitly timetabled (unless the order is conditional). */
-	inline void SetTravelTimetabled(bool timetabled) { if (!this->IsType(OT_CONDITIONAL)) SB(this->flags, 7, 1, timetabled ? 1 : 0); }
+	inline void SetTravelTimetabled(bool timetabled)
+	{
+		if (!this->IsType(OT_CONDITIONAL) && !this->HasNoTimetableTimes()) SB(this->flags, 7, 1, timetabled ? 1 : 0);
+	}
 
 	/**
 	 * Set the time in ticks to wait at the destination.

src/timetable_cmd.cpp

@@ -37,6 +37,8 @@ static void ChangeTimetable(Vehicle *v, VehicleOrderID order_number, uint32 val,
 {
 	Order *order = v->GetOrder(order_number);
 	assert(order != nullptr);
+	if (order->HasNoTimetableTimes()) return;
+
 	int total_delta = 0;
 	int timetable_delta = 0;
 
@@ -175,7 +177,7 @@ CommandCost CmdChangeTimetable(TileIndex tile, DoCommandFlag flags, uint32 p1, u
 
 	VehicleOrderID order_number = GB(p3,  0, 16);
 	Order *order = v->GetOrder(order_number);
-	if (order == nullptr || order->IsType(OT_IMPLICIT)) return CMD_ERROR;
+	if (order == nullptr || order->IsType(OT_IMPLICIT) || order->HasNoTimetableTimes()) return CMD_ERROR;
 
 	ModifyTimetableFlags mtf = Extract<ModifyTimetableFlags, 28, 3>(p1);
 	if (mtf >= MTF_END) return CMD_ERROR;
@@ -661,6 +663,8 @@ CommandCost CmdTimetableSeparation(TileIndex tile, DoCommandFlag flags, uint32 p
 
 static inline bool IsOrderUsableForSeparation(const Order *order)
 {
+	if (order->HasNoTimetableTimes()) return true;
+
 	if (order->GetWaitTime() == 0 && order->IsType(OT_GOTO_STATION) && !(order->GetNonStopType() & ONSF_NO_STOP_AT_DESTINATION_STATION)) {
 		// non-station orders are permitted to have 0 wait times
 		return false;

src/timetable_gui.cpp

@@ -550,7 +550,7 @@ struct TimetableWindow : GeneralVehicleWindow {
 				const Order *order = v->GetOrder(((selected + 1) / 2) % v->GetNumOrders());
 				if (selected % 2 != 0) {
 					/* Travel time */
-					disable = order != nullptr && (order->IsType(OT_CONDITIONAL) || order->IsType(OT_IMPLICIT));
+					disable = order != nullptr && (order->IsType(OT_CONDITIONAL) || order->IsType(OT_IMPLICIT) || order->HasNoTimetableTimes());
 					disable_time = disable;
 					wait_lockable = !disable;
 					wait_locked = wait_lockable && order->IsTravelFixed();
@@ -699,7 +699,7 @@ struct TimetableWindow : GeneralVehicleWindow {
 					} else {
 						StringID string;
 						TextColour colour = (i == selected) ? TC_WHITE : TC_BLACK;
-						if (order->IsType(OT_CONDITIONAL)) {
+						if (order->IsType(OT_CONDITIONAL) || order->HasNoTimetableTimes()) {
 							string = STR_TIMETABLE_NO_TRAVEL;
 						} else if (order->IsType(OT_IMPLICIT)) {
 							string = STR_TIMETABLE_NOT_TIMETABLEABLE;