Misc API Enhancements (#5975)

- Write map tags array in `wl_map_info`
- Add function `LuaWorker::evict`
- Add property `LuaMapObject.exists`
- Expose worker buildcost to `modify_unit`

src/logic/map_objects/tribes/worker_descr.h

@@ -58,6 +58,9 @@ class WorkerDescr : public BobDescr {
 		assert(is_buildable());
 		return buildcost_;
 	}
+	[[nodiscard]] Buildcost& mutable_buildcost() {
+		return buildcost_;
+	}
 
 	[[nodiscard]] const Vector2i& ware_hotspot() const {
 		return ware_hotspot_;

src/scripting/lua_map.cc

@@ -4585,10 +4585,8 @@ const MethodType<LuaMapObject> LuaMapObject::Methods[] = {
    {nullptr, nullptr},
 };
 const PropertyType<LuaMapObject> LuaMapObject::Properties[] = {
-   PROP_RO(LuaMapObject, __hash),
-   PROP_RO(LuaMapObject, descr),
-   PROP_RO(LuaMapObject, serial),
-   {nullptr, nullptr, nullptr},
+   PROP_RO(LuaMapObject, __hash), PROP_RO(LuaMapObject, descr), PROP_RO(LuaMapObject, serial),
+   PROP_RO(LuaMapObject, exists), {nullptr, nullptr, nullptr},
 };
 
 void LuaMapObject::__persist(lua_State* L) {
@@ -4664,6 +4662,20 @@ int LuaMapObject::get_descr(lua_State* L) {
 	return upcasted_map_object_descr_to_lua(L, desc);
 }
 
+/* RST
+   .. attribute:: exists
+
+      .. versionadded:: 1.2
+
+      (RO) Whether the map object represented by this Lua object still exists.
+
+      If it does not exist, no other attributes or functions of this object may be accessed.
+*/
+int LuaMapObject::get_exists(lua_State* L) {
+	lua_pushboolean(L, static_cast<int>(get_or_zero(get_egbase(L)) != nullptr));
+	return 1;
+}
+
 /*
  ==========================================================
  LUA METHODS
@@ -7491,6 +7503,7 @@ Worker
 
 const char LuaWorker::className[] = "Worker";
 const MethodType<LuaWorker> LuaWorker::Methods[] = {
+   METHOD(LuaWorker, evict),
    {nullptr, nullptr},
 };
 const PropertyType<LuaWorker> LuaWorker::Properties[] = {
@@ -7539,6 +7552,19 @@ int LuaWorker::get_location(lua_State* L) {
  ==========================================================
  */
 
+/* RST
+   .. method:: evict()
+
+      .. versionadded:: 1.2
+
+      Evict this worker from his current workplace.
+*/
+int LuaWorker::evict(lua_State* L) {
+	Widelands::Game& game = get_game(L);
+	get(L, game)->evict(game);
+	return 0;
+}
+
 /*
  ==========================================================
  C METHODS

src/scripting/lua_map.h

@@ -877,6 +877,7 @@ class LuaMapObject : public LuaMapModuleClass {
 	CLANG_DIAG_RESERVED_IDENTIFIER_ON
 	int get_descr(lua_State*);
 	int get_serial(lua_State*);
+	int get_exists(lua_State*);
 
 	/*
 	 * Lua Methods
@@ -1359,6 +1360,7 @@ class LuaWorker : public LuaBob {
 	/*
 	 * Lua methods
 	 */
+	int evict(lua_State* L);
 
 	/*
 	 * C methods

src/scripting/lua_root.cc

@@ -758,6 +758,9 @@ int LuaDescriptions::new_tribe(lua_State* L) {
          :const:`"becomes"`                            **worker_name**    (*string*)            1.0
          :const:`"programs"`, :const:`"set"`           **program_name**   (*string*),           1.0
                                                        **actions_table**  (*table*)
+         :const:`"buildcost"`, :const:`"set"`          **ware_name**      (*string*),           1.2
+                                                       **amount**         (*int*)
+         :const:`"buildcost"`, :const:`"remove"`       **ware_name**      (*string*),           1.2
          ============================================  =======================================  =============
 
       .. table:: ``"building"``
@@ -1106,6 +1109,17 @@ void LuaDescriptions::do_modify_worker(lua_State* L,
 		} else {
 			report_error(L, "modify_unit - worker - programs: invalid command '%s'", cmd.c_str());
 		}
+	} else if (property == "buildcost") {
+		const std::string cmd = luaL_checkstring(L, 5);
+		const std::string item_name = luaL_checkstring(L, 6);
+		Widelands::WorkerDescr::Buildcost& bc = worker_descr.mutable_buildcost();
+		if (cmd == "remove") {
+			bc.erase(item_name);
+		} else if (cmd == "set") {
+			bc[item_name] = luaL_checkuint32(L, 7);
+		} else {
+			report_error(L, "modify_unit - worker - buildcost: invalid command '%s'", cmd.c_str());
+		}
 	} else {
 		report_error(L, "modify_unit: invalid worker property '%s'", property.c_str());
 	}

src/website/map_info.cc

@@ -92,6 +92,11 @@ int main(int argc, char** argv) {
 			json->add_string(
 			   "minimum_required_widelands_version", map->minimum_required_widelands_version());
 
+			JSON::Array* tags_array = json->add_array("tags");
+			for (const std::string& tag : map->get_tags()) {
+				tags_array->add_empty(tag);
+			}
+
 			const std::string world_name =
 			   dynamic_cast<Widelands::WidelandsMapLoader*>(ml.get())->old_world_name();
 			json->add_string("world_name", world_name);

test/maps/plain.wmf/scripting/test_casern.lua

@@ -86,6 +86,27 @@ run(function()
    rv = hq:get_workers("all")
    assert_equal(5, rv.barbarians_soldier)
 
+   -- Cut the road
+   fhq.fields[1].rn.immovable:destroy()
+
+   -- Test evicting and map object existence checks
+   assert_equal(1, br:get_workers("barbarians_trainer"))
+   local main_worker
+   for i,bob in ipairs(br.fields[1].bobs) do
+      if bob.descr.name == "barbarians_trainer" then
+         assert_nil(main_worker)
+         main_worker = bob
+      end
+   end
+   assert_not_nil(main_worker)
+   main_worker:evict()
+   sleep(10000)
+   assert_equal(0, br:get_workers("barbarians_trainer"))
+
+   assert(br.exists)
+   br:destroy()
+   assert_equal(false, br.exists)
+
    print("# All Tests passed.")
    wl.ui.MapView():close()
 end)