Add: precondition checks to functions that work with both valid company and deity

These are functions that either use ScriptObject::Command or ScriptObject::GetCompany.
This is a bit over-protective, but having the check everywhere makes it easier to
validate that no check is missing automatically instead of by review.

At this moment these checks will not do anything useful, as either IsValid or
IsDeity from ScriptCompanyMode returns true, but that will change later.

src/script/api/script_airport.cpp

@@ -91,6 +91,7 @@
 
 /* static */ SQInteger ScriptAirport::GetNumHangars(TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid(-1);
 	if (!::IsValidTile(tile)) return -1;
 	if (!::IsTileType(tile, MP_STATION)) return -1;
 
@@ -103,6 +104,7 @@
 
 /* static */ TileIndex ScriptAirport::GetHangarOfAirport(TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid(INVALID_TILE);
 	if (!::IsValidTile(tile)) return INVALID_TILE;
 	if (!::IsTileType(tile, MP_STATION)) return INVALID_TILE;
 	if (GetNumHangars(tile) < 1) return INVALID_TILE;

src/script/api/script_basestation.cpp

@@ -21,6 +21,7 @@
 
 /* static */ bool ScriptBaseStation::IsValidBaseStation(StationID station_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const BaseStation *st = ::BaseStation::GetIfValid(station_id);
 	return st != nullptr && (st->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity() || st->owner == OWNER_NONE);
 }

src/script/api/script_bridge.cpp

@@ -72,6 +72,7 @@ static void _DoCommandReturnBuildBridge1(class ScriptInstance *instance)
 
 /* static */ bool ScriptBridge::BuildBridge(ScriptVehicle::VehicleType vehicle_type, BridgeID bridge_id, TileIndex start, TileIndex end)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, start != end);
 	EnforcePrecondition(false, ::IsValidTile(start) && ::IsValidTile(end));
 	EnforcePrecondition(false, TileX(start) == TileX(end) || TileY(start) == TileY(end));
@@ -95,6 +96,8 @@ static void _DoCommandReturnBuildBridge1(class ScriptInstance *instance)
 
 /* static */ bool ScriptBridge::_BuildBridgeRoad1()
 {
+	EnforceDeityOrCompanyModeValid(false);
+
 	/* Build the piece of road on the 'start' side of the bridge */
 	TileIndex end = ScriptObject::GetCallbackVariable(0);
 	TileIndex start = ScriptObject::GetCallbackVariable(1);
@@ -107,6 +110,8 @@ static void _DoCommandReturnBuildBridge1(class ScriptInstance *instance)
 
 /* static */ bool ScriptBridge::_BuildBridgeRoad2()
 {
+	EnforceDeityOrCompanyModeValid(false);
+
 	/* Build the piece of road on the 'end' side of the bridge */
 	TileIndex end = ScriptObject::GetCallbackVariable(0);
 	TileIndex start = ScriptObject::GetCallbackVariable(1);

src/script/api/script_depotlist.cpp

@@ -16,6 +16,7 @@
 
 ScriptDepotList::ScriptDepotList(ScriptTile::TransportType transport_type)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	::TileType tile_type;
 	switch (transport_type) {
 		default: return;

src/script/api/script_engine.cpp

@@ -24,6 +24,7 @@
 
 /* static */ bool ScriptEngine::IsValidEngine(EngineID engine_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Engine *e = ::Engine::GetIfValid(engine_id);
 	if (e == nullptr || !e->IsEnabled()) return false;
 
@@ -35,6 +36,7 @@
 
 /* static */ bool ScriptEngine::IsBuildable(EngineID engine_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Engine *e = ::Engine::GetIfValid(engine_id);
 	return e != nullptr && ::IsEngineBuildable(engine_id, e->type, ScriptObject::GetCompany());
 }

src/script/api/script_enginelist.cpp

@@ -15,6 +15,7 @@
 
 ScriptEngineList::ScriptEngineList(ScriptVehicle::VehicleType vehicle_type)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (const Engine *e : Engine::IterateType((::VehicleType)vehicle_type)) {
 		if (ScriptCompanyMode::IsDeity() || HasBit(e->company_avail, ScriptObject::GetCompany())) this->AddItem(e->index);
 	}

src/script/api/script_error.hpp

@@ -62,6 +62,23 @@
 #define EnforceDeityMode(returnval) \
 	EnforcePreconditionCustomError(returnval, ScriptCompanyMode::IsDeity(), ScriptError::ERR_PRECONDITION_INVALID_COMPANY)
 
+/**
+ * Helper to enforce the precondition that the company mode is valid or that we are a deity.
+ * @param returnval The value to return on failure.
+ */
+#define EnforceDeityOrCompanyModeValid(returnval) \
+	EnforcePreconditionCustomError(returnval, ScriptCompanyMode::IsDeity() || ScriptCompanyMode::IsValid(), ScriptError::ERR_PRECONDITION_INVALID_COMPANY)
+
+/**
+ * Helper to enforce the precondition that the company mode is valid or that we are a deity.
+ */
+#define EnforceDeityOrCompanyModeValid_Void() \
+	if (!(ScriptCompanyMode::IsDeity() || ScriptCompanyMode::IsValid())) { \
+		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_INVALID_COMPANY); \
+		return; \
+	}
+
+
 /**
  * Class that handles all error related functions.
  * @api ai game

src/script/api/script_game.cpp

@@ -9,6 +9,7 @@
 
 #include "../../stdafx.h"
 #include "script_game.hpp"
+#include "script_error.hpp"
 #include "../../command_type.h"
 #include "../../settings_type.h"
 #include "../../network/network.h"

src/script/api/script_gamesettings.cpp

@@ -33,6 +33,7 @@
 
 /* static */ bool ScriptGameSettings::SetValue(const char *setting, SQInteger value)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	if (!IsValid(setting)) return false;
 
 	const SettingDesc *sd = GetSettingFromName(setting);

src/script/api/script_group.cpp

@@ -25,6 +25,7 @@
 
 /* static */ bool ScriptGroup::IsValidGroup(GroupID group_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Group *g = ::Group::GetIfValid(group_id);
 	return g != nullptr && g->owner == ScriptObject::GetCompany();
 }

src/script/api/script_grouplist.cpp

@@ -9,12 +9,14 @@
 
 #include "../../stdafx.h"
 #include "script_grouplist.hpp"
+#include "script_error.hpp"
 #include "../../group.h"
 
 #include "../../safeguards.h"
 
 ScriptGroupList::ScriptGroupList()
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (const Group *g : Group::Iterate()) {
 		if (g->owner == ScriptObject::GetCompany()) this->AddItem(g->index);
 	}

src/script/api/script_industrytype.cpp

@@ -119,6 +119,7 @@
 
 /* static */ bool ScriptIndustryType::BuildIndustry(IndustryType industry_type, TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, CanBuildIndustry(industry_type));
 	EnforcePrecondition(false, ScriptMap::IsValidTile(tile));
 
@@ -129,6 +130,7 @@
 
 /* static */ bool ScriptIndustryType::ProspectIndustry(IndustryType industry_type)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, CanProspectIndustry(industry_type));
 
 	uint32 seed = ScriptBase::Rand();

src/script/api/script_objecttype.cpp

@@ -39,6 +39,7 @@
 
 /* static */ bool ScriptObjectType::BuildObject(ObjectType object_type, SQInteger view, TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, IsValidObjectType(object_type));
 	EnforcePrecondition(false, view >= 0 && view < GetViews(object_type));
 	EnforcePrecondition(false, ScriptMap::IsValidTile(tile));

src/script/api/script_rail.cpp

@@ -69,6 +69,7 @@
 
 /* static */ bool ScriptRail::IsRailTypeAvailable(RailType rail_type)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	if ((::RailType)rail_type >= RAILTYPE_END) return false;
 
 	return ScriptCompanyMode::IsDeity() || ::HasRailtypeAvail(ScriptObject::GetCompany(), (::RailType)rail_type);

src/script/api/script_railtypelist.cpp

@@ -9,13 +9,14 @@
 
 #include "../../stdafx.h"
 #include "script_railtypelist.hpp"
-#include "script_companymode.hpp"
+#include "script_error.hpp"
 #include "../../rail.h"
 
 #include "../../safeguards.h"
 
 ScriptRailTypeList::ScriptRailTypeList()
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
 		if (ScriptCompanyMode::IsDeity() || ::HasRailtypeAvail(ScriptObject::GetCompany(), rt)) this->AddItem(rt);
 	}

src/script/api/script_road.cpp

@@ -67,6 +67,7 @@
 
 /* static */ bool ScriptRoad::IsRoadTypeAvailable(RoadType road_type)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	return (::RoadType)road_type < ROADTYPE_END && ::HasRoadTypeAvail(ScriptObject::GetCompany(), (::RoadType)road_type);
 }
 
@@ -489,6 +490,7 @@ static bool NeighbourHasReachableRoad(::RoadType rt, TileIndex start_tile, DiagD
 
 /* static */ bool ScriptRoad::_BuildRoadInternal(TileIndex start, TileIndex end, bool one_way, bool full)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, start != end);
 	EnforcePrecondition(false, ::IsValidTile(start));
 	EnforcePrecondition(false, ::IsValidTile(end));

src/script/api/script_roadtypelist.cpp

@@ -15,6 +15,7 @@
 
 ScriptRoadTypeList::ScriptRoadTypeList(ScriptRoad::RoadTramTypes rtts)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (RoadType rt = ROADTYPE_BEGIN; rt != ROADTYPE_END; rt++) {
 		if (!HasBit(rtts, GetRoadTramType(rt))) continue;
 		if (ScriptCompanyMode::IsDeity() || ::HasRoadTypeAvail(ScriptObject::GetCompany(), rt)) this->AddItem(rt);

src/script/api/script_sign.cpp

@@ -21,6 +21,7 @@
 
 /* static */ bool ScriptSign::IsValidSign(SignID sign_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Sign *si = ::Sign::GetIfValid(sign_id);
 	return si != nullptr && (si->owner == ScriptObject::GetCompany() || si->owner == OWNER_DEITY);
 }
@@ -36,6 +37,7 @@
 {
 	CCountedPtr<Text> counter(name);
 
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, IsValidSign(sign_id));
 	EnforcePrecondition(false, name != nullptr);
 	const std::string &text = name->GetDecodedText();
@@ -63,6 +65,7 @@
 
 /* static */ bool ScriptSign::RemoveSign(SignID sign_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, IsValidSign(sign_id));
 	return ScriptObject::Command<CMD_RENAME_SIGN>::Do(sign_id, "");
 }
@@ -71,6 +74,7 @@
 {
 	CCountedPtr<Text> counter(name);
 
+	EnforceDeityOrCompanyModeValid(INVALID_SIGN);
 	EnforcePrecondition(INVALID_SIGN, ::IsValidTile(location));
 	EnforcePrecondition(INVALID_SIGN, name != nullptr);
 	const std::string &text = name->GetDecodedText();

src/script/api/script_station.cpp

@@ -21,6 +21,7 @@
 
 /* static */ bool ScriptStation::IsValidStation(StationID station_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Station *st = ::Station::GetIfValid(station_id);
 	return st != nullptr && (st->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity() || st->owner == OWNER_NONE);
 }

src/script/api/script_stationlist.cpp

@@ -18,6 +18,7 @@
 
 ScriptStationList::ScriptStationList(ScriptStation::StationType station_type)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (Station *st : Station::Iterate()) {
 		if ((st->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity()) && (st->facilities & station_type) != 0) this->AddItem(st->index);
 	}

src/script/api/script_tile.cpp

@@ -25,6 +25,7 @@
 
 /* static */ bool ScriptTile::IsBuildable(TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	if (!::IsValidTile(tile)) return false;
 
 	switch (::GetTileType(tile)) {
@@ -277,6 +278,7 @@
 
 /* static */ bool ScriptTile::DemolishTile(TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, ::IsValidTile(tile));
 
 	return ScriptObject::Command<CMD_LANDSCAPE_CLEAR>::Do(tile);

src/script/api/script_town.cpp

@@ -281,6 +281,7 @@
 {
 	CCountedPtr<Text> counter(name);
 
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, ScriptCompanyMode::IsDeity() || _settings_game.economy.found_town != TF_FORBIDDEN);
 	EnforcePrecondition(false, ::IsValidTile(tile));
 	EnforcePrecondition(false, size == TOWN_SIZE_SMALL || size == TOWN_SIZE_MEDIUM || size == TOWN_SIZE_LARGE)

src/script/api/script_tunnel.cpp

@@ -82,6 +82,7 @@ static void _DoCommandReturnBuildTunnel1(class ScriptInstance *instance)
 
 /* static */ bool ScriptTunnel::BuildTunnel(ScriptVehicle::VehicleType vehicle_type, TileIndex start)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	EnforcePrecondition(false, ::IsValidTile(start));
 	EnforcePrecondition(false, vehicle_type == ScriptVehicle::VT_RAIL || vehicle_type == ScriptVehicle::VT_ROAD);
 	EnforcePrecondition(false, vehicle_type != ScriptVehicle::VT_RAIL || ScriptRail::IsRailTypeAvailable(ScriptRail::GetCurrentRailType()));
@@ -99,6 +100,8 @@ static void _DoCommandReturnBuildTunnel1(class ScriptInstance *instance)
 
 /* static */ bool ScriptTunnel::_BuildTunnelRoad1()
 {
+	EnforceDeityOrCompanyModeValid(false);
+
 	/* Build the piece of road on the 'start' side of the tunnel */
 	TileIndex end = ScriptObject::GetCallbackVariable(0);
 	TileIndex start = ScriptTunnel::GetOtherTunnelEnd(end);
@@ -111,6 +114,8 @@ static void _DoCommandReturnBuildTunnel1(class ScriptInstance *instance)
 
 /* static */ bool ScriptTunnel::_BuildTunnelRoad2()
 {
+	EnforceDeityOrCompanyModeValid(false);
+
 	/* Build the piece of road on the 'end' side of the tunnel */
 	TileIndex end = ScriptObject::GetCallbackVariable(0);
 	TileIndex start = ScriptTunnel::GetOtherTunnelEnd(end);

src/script/api/script_vehicle.cpp

@@ -30,6 +30,7 @@
 
 /* static */ bool ScriptVehicle::IsValidVehicle(VehicleID vehicle_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Vehicle *v = ::Vehicle::GetIfValid(vehicle_id);
 	return v != nullptr && (v->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity()) && (v->IsPrimaryVehicle() || (v->type == VEH_TRAIN && ::Train::From(v)->IsFreeWagon()));
 }

src/script/api/script_vehiclelist.cpp

@@ -20,6 +20,7 @@
 
 ScriptVehicleList::ScriptVehicleList()
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (const Vehicle *v : Vehicle::Iterate()) {
 		if ((v->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity()) && (v->IsPrimaryVehicle() || (v->type == VEH_TRAIN && ::Train::From(v)->IsFreeWagon()))) this->AddItem(v->index);
 	}
@@ -27,6 +28,7 @@ ScriptVehicleList::ScriptVehicleList()
 
 ScriptVehicleList_Station::ScriptVehicleList_Station(StationID station_id)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	if (!ScriptBaseStation::IsValidBaseStation(station_id)) return;
 
 	for (const Vehicle *v : Vehicle::Iterate()) {
@@ -43,6 +45,7 @@ ScriptVehicleList_Station::ScriptVehicleList_Station(StationID station_id)
 
 ScriptVehicleList_Depot::ScriptVehicleList_Depot(TileIndex tile)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	if (!ScriptMap::IsValidTile(tile)) return;
 
 	DestinationID dest;
@@ -100,6 +103,7 @@ ScriptVehicleList_SharedOrders::ScriptVehicleList_SharedOrders(VehicleID vehicle
 
 ScriptVehicleList_Group::ScriptVehicleList_Group(GroupID group_id)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	if (!ScriptGroup::IsValidGroup((ScriptGroup::GroupID)group_id)) return;
 
 	for (const Vehicle *v : Vehicle::Iterate()) {
@@ -111,6 +115,7 @@ ScriptVehicleList_Group::ScriptVehicleList_Group(GroupID group_id)
 
 ScriptVehicleList_DefaultGroup::ScriptVehicleList_DefaultGroup(ScriptVehicle::VehicleType vehicle_type)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	if (vehicle_type < ScriptVehicle::VT_RAIL || vehicle_type > ScriptVehicle::VT_AIR) return;
 
 	for (const Vehicle *v : Vehicle::Iterate()) {

src/script/api/script_waypoint.cpp

@@ -17,6 +17,7 @@
 
 /* static */ bool ScriptWaypoint::IsValidWaypoint(StationID waypoint_id)
 {
+	EnforceDeityOrCompanyModeValid(false);
 	const Waypoint *wp = ::Waypoint::GetIfValid(waypoint_id);
 	return wp != nullptr && (wp->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity() || wp->owner == OWNER_NONE);
 }

src/script/api/script_waypointlist.cpp

@@ -17,6 +17,7 @@
 
 ScriptWaypointList::ScriptWaypointList(ScriptWaypoint::WaypointType waypoint_type)
 {
+	EnforceDeityOrCompanyModeValid_Void();
 	for (const Waypoint *wp : Waypoint::Iterate()) {
 		if ((wp->facilities & waypoint_type) &&
 				(wp->owner == ScriptObject::GetCompany() || ScriptCompanyMode::IsDeity() || wp->owner == OWNER_NONE)) this->AddItem(wp->index);