5 files changed, 21 insertions, 12 deletions

diff --git a/src/base_station_base.h b/src/base_station_base.h
index d6d97cc83..e652c3264 100644
--- a/src/base_station_base.h
+++ b/src/base_station_base.h
@@ -41,7 +41,7 @@ struct StationRect : public Rect {
 	bool PtInExtendedRect(int x, int y, int distance = 0) const;
 	bool IsEmpty() const;
 	CommandCost BeforeAddTile(TileIndex tile, StationRectMode mode);
-	bool BeforeAddRect(TileIndex tile, int w, int h, StationRectMode mode);
+	CommandCost BeforeAddRect(TileIndex tile, int w, int h, StationRectMode mode);
 	bool AfterRemoveTile(BaseStation *st, TileIndex tile);
 	bool AfterRemoveRect(BaseStation *st, TileIndex tile, int w, int h);
 
diff --git a/src/station.cpp b/src/station.cpp
index 9ef44a280..416403048 100644
--- a/src/station.cpp
+++ b/src/station.cpp
@@ -400,16 +400,15 @@ CommandCost StationRect::BeforeAddTile(TileIndex tile, StationRectMode mode)
 	return CommandCost();
 }
 
-bool StationRect::BeforeAddRect(TileIndex tile, int w, int h, StationRectMode mode)
+CommandCost StationRect::BeforeAddRect(TileIndex tile, int w, int h, StationRectMode mode)
 {
 	if (mode == ADD_FORCE || (w <= _settings_game.station.station_spread && h <= _settings_game.station.station_spread)) {
 		/* Important when the old rect is completely inside the new rect, resp. the old one was empty. */
 		CommandCost ret = this->BeforeAddTile(tile, mode);
 		if (ret.Succeeded()) ret = this->BeforeAddTile(TILE_ADDXY(tile, w - 1, h - 1), mode);
-		if (ret.Succeeded()) return true;
-		ret.SetGlobalErrorMessage();
+		return ret;
 	}
-	return false;
+	return CommandCost();
 }
 
 /**
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index 17d110401..70f8690ef 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -1159,7 +1159,9 @@ CommandCost CmdBuildRailStation(TileIndex tile_org, DoCommandFlag flags, uint32
 		}
 
 		/* XXX can't we pack this in the "else" part of the if above? */
-		if (!st->rect.BeforeAddRect(tile_org, w_org, h_org, StationRect::ADD_TEST)) return CMD_ERROR;
+		CommandCost ret = st->rect.BeforeAddRect(tile_org, w_org, h_org, StationRect::ADD_TEST);
+		ret.SetGlobalErrorMessage();
+		if (ret.Failed()) return ret;
 	} else {
 		/* allocate and initialize new station */
 		if (!Station::CanAllocateItem()) return_cmd_error(STR_ERROR_TOO_MANY_STATIONS_LOADING);
@@ -1726,7 +1728,9 @@ CommandCost CmdBuildRoadStop(TileIndex tile, DoCommandFlag flags, uint32 p1, uin
 			return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_STATION);
 		}
 
-		if (!st->rect.BeforeAddRect(roadstop_area.tile, roadstop_area.w, roadstop_area.h, StationRect::ADD_TEST)) return CMD_ERROR;
+		CommandCost ret = st->rect.BeforeAddRect(roadstop_area.tile, roadstop_area.w, roadstop_area.h, StationRect::ADD_TEST);
+		ret.SetGlobalErrorMessage();
+		if (ret.Failed()) return ret;
 	} else {
 		/* allocate and initialize new station */
 		if (!Station::CanAllocateItem()) return_cmd_error(STR_ERROR_TOO_MANY_STATIONS_LOADING);
@@ -2137,7 +2141,9 @@ CommandCost CmdBuildAirport(TileIndex tile, DoCommandFlag flags, uint32 p1, uint
 			return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_STATION);
 		}
 
-		if (!st->rect.BeforeAddRect(tile, w, h, StationRect::ADD_TEST)) return CMD_ERROR;
+		CommandCost ret = st->rect.BeforeAddRect(tile, w, h, StationRect::ADD_TEST);
+		ret.SetGlobalErrorMessage();
+		if (ret.Failed()) return ret;
 
 		if (st->airport.tile != INVALID_TILE) {
 			return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_AIRPORT);
@@ -2385,9 +2391,11 @@ CommandCost CmdBuildDock(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 			return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_STATION);
 		}
 
-		if (!st->rect.BeforeAddRect(
+		CommandCost ret = st->rect.BeforeAddRect(
 				tile + ToTileIndexDiff(_dock_tileoffs_chkaround[direction]),
-				_dock_w_chk[direction], _dock_h_chk[direction], StationRect::ADD_TEST)) return CMD_ERROR;
+				_dock_w_chk[direction], _dock_h_chk[direction], StationRect::ADD_TEST);
+		ret.SetGlobalErrorMessage();
+		if (ret.Failed()) return ret;
 
 		if (st->dock_tile != INVALID_TILE) return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_DOCK);
 	} else {
diff --git a/src/station_gui.cpp b/src/station_gui.cpp
index 6efb569f2..e731931dd 100644
--- a/src/station_gui.cpp
+++ b/src/station_gui.cpp
@@ -1293,7 +1293,7 @@ static bool AddNearbyStation(TileIndex tile, void *user_data)
 	T *st = T::Get(sid);
 	if (st->owner != _local_company || _stations_nearby_list.Contains(sid)) return false;
 
-	if (st->rect.BeforeAddRect(ctx->tile, ctx->w, ctx->h, StationRect::ADD_TEST)) {
+	if (st->rect.BeforeAddRect(ctx->tile, ctx->w, ctx->h, StationRect::ADD_TEST).Succeeded()) {
 		*_stations_nearby_list.Append() = sid;
 	}
 
diff --git a/src/waypoint_cmd.cpp b/src/waypoint_cmd.cpp
index 7be4a6ce4..04db4fc93 100644
--- a/src/waypoint_cmd.cpp
+++ b/src/waypoint_cmd.cpp
@@ -273,7 +273,9 @@ CommandCost CmdBuildRailWaypoint(TileIndex start_tile, DoCommandFlag flags, uint
 			if (ret.Failed()) return ret;
 		}
 
-		if (!wp->rect.BeforeAddRect(start_tile, width, height, StationRect::ADD_TEST)) return CMD_ERROR;
+		CommandCost ret = wp->rect.BeforeAddRect(start_tile, width, height, StationRect::ADD_TEST);
+		ret.SetGlobalErrorMessage();
+		if (ret.Failed()) return ret;
 	} else {
 		/* allocate and initialize new waypoint */
 		if (!Waypoint::CanAllocateItem()) return_cmd_error(STR_ERROR_TOO_MANY_STATIONS_LOADING);