Add unit tests for SAO load / unload behaviour

src/script/scripting_server.cpp

@@ -21,6 +21,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "server.h"
 #include "log.h"
 #include "settings.h"
+#include "filesys.h"
 #include "cpp_api/s_internal.h"
 #include "lua_api/l_areastore.h"
 #include "lua_api/l_auth.h"
@@ -89,6 +90,12 @@ ServerScripting::ServerScripting(Server* server):
 	infostream << "SCRIPTAPI: Initialized game modules" << std::endl;
 }
 
+void ServerScripting::loadBuiltin()
+{
+	loadMod(Server::getBuiltinLuaPath() + DIR_DELIM "init.lua", BUILTIN_MOD_NAME);
+	checkSetByBuiltin();
+}
+
 void ServerScripting::saveGlobals()
 {
 	SCRIPTAPI_PRECHECKHEADER

src/script/scripting_server.h

@@ -49,6 +49,7 @@ class ServerScripting:
 public:
 	ServerScripting(Server* server);
 
+	void loadBuiltin();
 	// use ScriptApiBase::loadMod() to load mods
 
 	// Save globals that are copied into other Lua envs

src/server.cpp

@@ -471,8 +471,7 @@ void Server::init()
 	// Must be created before mod loading because we have some inventory creation
 	m_inventory_mgr = std::make_unique<ServerInventoryManager>();
 
-	m_script->loadMod(getBuiltinLuaPath() + DIR_DELIM "init.lua", BUILTIN_MOD_NAME);
-	m_script->checkSetByBuiltin();
+	m_script->loadBuiltin();
 
 	m_gamespec.checkAndLog();
 	m_modmgr->loadMods(m_script);

src/serverenvironment.cpp

@@ -1642,7 +1642,8 @@ void ServerEnvironment::step(float dtime)
 	}
 
 	// Send outdated detached inventories
-	m_server->sendDetachedInventories(PEER_ID_INEXISTENT, true);
+	if (!m_players.empty())
+		m_server->sendDetachedInventories(PEER_ID_INEXISTENT, true);
 
 	// Notify mods of modified mapblocks
 	if (m_on_mapblocks_changed_receiver.receiving &&

src/unittest/CMakeLists.txt

@@ -26,6 +26,7 @@ set (UNITTEST_SRCS
 	${CMAKE_CURRENT_SOURCE_DIR}/test_objdef.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_profiler.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_random.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/test_sao.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_schematic.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_serialization.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_serveractiveobjectmgr.cpp

src/unittest/mock_server.h

@@ -19,7 +19,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #pragma once
 
-#include <server.h>
+#include "server.h"
 
 class MockServer : public Server
 {
@@ -31,6 +31,9 @@ public:
 		)
 	{}
 
+	void start() = delete;
+	void stop() = delete;
+
 private:
 	void SendChatMessage(session_t peer_id, const ChatMessage &message) {}
 };

src/unittest/test_moveaction.cpp

@@ -22,11 +22,9 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "mock_inventorymanager.h"
 #include "mock_server.h"
 #include "mock_serveractiveobject.h"
-
 #include "scripting_server.h"
 #include "server/mods.h"
 
-
 class TestMoveAction : public TestBase
 {
 public:
@@ -63,7 +61,7 @@ void TestMoveAction::runTests(IGameDef *gamedef)
 		server.m_modmgr = std::make_unique<ServerModManager>(server.m_path_world);
 
 		std::string builtin = Server::getBuiltinLuaPath() + DIR_DELIM;
-		server_scripting.loadMod(builtin + "init.lua", BUILTIN_MOD_NAME);
+		server_scripting.loadBuiltin();
 		server_scripting.loadMod(builtin + "game" DIR_DELIM "tests" DIR_DELIM "test_moveaction.lua", BUILTIN_MOD_NAME);
 	} catch (ModError &e) {
 		// Print backtrace in case of syntax errors

src/unittest/test_sao.cpp

@@ -0,0 +1,315 @@
+/*
+Minetest
+Copyright (C) 2024 sfan5
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "test.h"
+
+#include "mock_server.h"
+#include "scripting_server.h"
+#include "server/luaentity_sao.h"
+#include "emerge.h"
+
+/*
+ * Tests how SAOs behave in the server environment.
+ * See also test_serveractiveobjectmgr.cpp and test_activeobject.cpp for other tests.
+ */
+
+class TestSAO : public TestBase
+{
+public:
+	TestSAO() { TestManager::registerTestModule(this); }
+	const char *getName() { return "TestSAO"; }
+
+	void runTests(IGameDef *gamedef);
+
+	void testStaticSave(ServerEnvironment *env);
+	void testNotSaved(ServerEnvironment *env);
+	void testActivate(ServerEnvironment *env);
+	void testStaticToFalse(ServerEnvironment *env);
+	void testStaticToTrue(ServerEnvironment *env);
+
+private:
+	// enough for both removeRemovedObjects and deactivateFarObjects to be called
+	// use as param to ServerEnvironment::step()
+	float m_step_interval;
+};
+
+static TestSAO g_test_instance;
+
+const static char *helper_lua_src = R"(
+core.register_entity(":test:static", {})
+core.register_entity(":test:non_static", {
+	initial_properties = {
+		static_save = false,
+	}
+})
+)";
+
+void TestSAO::runTests(IGameDef *gamedef)
+{
+	MockServer server(getTestTempDirectory());
+
+	const auto helper_lua = getTestTempFile();
+	{
+		std::ofstream ofs(helper_lua, std::ios::out | std::ios::binary);
+		ofs << helper_lua_src;
+		std::ofstream ofs2(server.getWorldPath() + DIR_DELIM "world.mt",
+			std::ios::out | std::ios::binary);
+		ofs2 << "backend = dummy\n";
+	}
+
+	ServerScripting server_scripting(&server);
+	try {
+		server_scripting.loadBuiltin();
+		server_scripting.loadMod(helper_lua, BUILTIN_MOD_NAME);
+	} catch (ModError &e) {
+		rawstream << e.what() << std::endl;
+		num_tests_failed = 1;
+		return;
+	}
+
+	// unfortunately we have to create a lot since a DummyMap doesn't cut it.
+	// TODO: best to factor entity mgmt out of ServerEnvironment, also
+	//       EmergeManager should become mockable
+	MetricsBackend mb;
+	EmergeManager emerge(&server, &mb);
+	auto *map = new ServerMap(server.getWorldPath(), gamedef, &emerge, &mb);
+	ServerEnvironment env(map, &server_scripting, &server, "", &mb);
+	env.loadMeta();
+
+	m_step_interval = std::max(
+		g_settings->getFloat("active_block_mgmt_interval"), 0.5f) + 0.1f;
+
+	TEST(testStaticSave, &env);
+	TEST(testNotSaved, &env);
+	TEST(testActivate, &env);
+	TEST(testStaticToFalse, &env);
+	TEST(testStaticToTrue, &env);
+
+	env.deactivateBlocksAndObjects();
+}
+
+static LuaEntitySAO *add_entity(ServerEnvironment *env, v3f pos, const char *name)
+{
+	auto obj_u = std::make_unique<LuaEntitySAO>(env, pos, name, "");
+	auto obj = obj_u.get();
+	u16 id = env->addActiveObject(std::move(obj_u));
+	if (!id || obj->isGone())
+		return nullptr;
+	return obj;
+}
+
+static u16 assert_active_in_block(MapBlock *block, u16 obj_id = 0)
+{
+	const auto &so = block->m_static_objects;
+	UASSERTEQ(size_t, so.getStoredSize(), 0);
+	UASSERTEQ(size_t, so.getActiveSize(), 1);
+	if (obj_id) {
+		UASSERT(so.getAllActives().count(obj_id) == 1);
+	} else {
+		obj_id = so.getAllActives().begin()->first;
+		UASSERT(obj_id != 0);
+	}
+	return obj_id;
+}
+
+void TestSAO::testStaticSave(ServerEnvironment *env)
+{
+	Map &map = env->getMap();
+
+	const v3f testpos(0, -66 * BS, 0);
+	const v3s16 testblockpos = getNodeBlockPos(floatToInt(testpos, BS));
+
+	auto obj = add_entity(env, testpos, "test:static");
+	UASSERT(obj);
+	const u16 obj_id = obj->getId();
+
+	// static data should have been created
+	UASSERT(obj->accessObjectProperties()->static_save);
+	UASSERT(obj->m_static_exists);
+	UASSERTEQ(auto, obj->m_static_block, testblockpos);
+	// check that it's really in there
+	auto *block = map.getBlockNoCreateNoEx(testblockpos);
+	UASSERT(block);
+	assert_active_in_block(block, obj_id);
+
+	// Since we have no active blocks, stepping will deactivate it.
+	env->step(m_step_interval);
+
+	obj = nullptr; // dangling reference
+	UASSERT(!env->getActiveObject(obj_id));
+	UASSERTEQ(size_t, block->m_static_objects.getStoredSize(), 1);
+	UASSERTEQ(size_t, block->m_static_objects.getActiveSize(), 0);
+}
+
+void TestSAO::testNotSaved(ServerEnvironment *env)
+{
+	Map &map = env->getMap();
+
+	const v3f testpos(0, 4 * BS, 0);
+	const v3s16 testblockpos = getNodeBlockPos(floatToInt(testpos, BS));
+
+	// make sure matching block exists (see below)
+	auto *block = map.emergeBlock(testblockpos, true);
+	UASSERT(block);
+
+	auto obj = add_entity(env, testpos, "test:non_static");
+	UASSERT(obj);
+	const u16 obj_id = obj->getId();
+
+	UASSERT(!obj->accessObjectProperties()->static_save);
+	UASSERT(!obj->m_static_exists);
+	UASSERTEQ(size_t, block->m_static_objects.size(), 0);
+
+	// Non-static objects are only unloaded together with their block, so doing
+	// this will *not* delete it.
+	env->step(m_step_interval);
+
+	UASSERT(env->getActiveObject(obj_id) == obj);
+
+	// Here we force the block to be unloaded, this has the expected effect.
+	map.timerUpdate(10.0f, 5.0f, -1);
+	env->step(m_step_interval);
+
+	block = nullptr;
+	obj = nullptr;
+	UASSERT(!env->getActiveObject(obj_id));
+	block = map.emergeBlock(testblockpos, false);
+	if (block)
+		UASSERTEQ(size_t, block->m_static_objects.size(), 0);
+}
+
+void TestSAO::testActivate(ServerEnvironment *env)
+{
+	Map &map = env->getMap();
+
+	const v3f testpos(0, 0, 100 * BS);
+	const v3s16 testblockpos = getNodeBlockPos(floatToInt(testpos, BS));
+
+	// this time insert the static object manually
+	StaticObject s_obj;
+	{
+		auto obj = std::make_unique<LuaEntitySAO>(env, testpos, "test:static", "");
+		s_obj = StaticObject(obj.get(), obj->getBasePosition());
+	}
+
+	auto *block = map.emergeBlock(testblockpos, true);
+	UASSERT(block);
+	block->m_static_objects.insert(0, s_obj);
+
+	// Activating the block will convert it to active.
+	env->activateBlock(block);
+
+	const u16 obj_id = assert_active_in_block(block);
+	auto *obj = env->getActiveObject(obj_id);
+	UASSERT(obj);
+
+	// same conditions as testStaticSave
+	UASSERT(obj->m_static_exists);
+	UASSERTEQ(auto, obj->m_static_block, testblockpos);
+
+	// let the object be deactivated, it causes a warning when we unload
+	// MapBlocks in further tests otherwise
+	// FIXME: figure out if this is a bug that needs to be fixed
+	env->step(m_step_interval);
+}
+
+void TestSAO::testStaticToFalse(ServerEnvironment *env)
+{
+	Map &map = env->getMap();
+
+	const v3f testpos(0, 0, -22 * BS);
+	const v3s16 testblockpos = getNodeBlockPos(floatToInt(testpos, BS));
+
+	/*
+	 * This test represents an edge case where static_save changed from true
+	 * to false while the server was off.
+	 */
+
+	StaticObject s_obj;
+	{
+		auto obj = std::make_unique<LuaEntitySAO>(env, testpos, "test:non_static", "");
+		// since the object is not added, it doesn't read info from Lua and retains
+		// the default value. This is what allows us to do this.
+		UASSERT(obj->isStaticAllowed());
+		s_obj = StaticObject(obj.get(), obj->getBasePosition());
+	}
+
+	auto *block = map.emergeBlock(testblockpos, true);
+	UASSERT(block);
+	block->m_static_objects.insert(0, s_obj);
+
+	env->activateBlock(block);
+
+	const u16 obj_id = assert_active_in_block(block);
+	auto *obj = env->getActiveObject(obj_id);
+	UASSERT(obj);
+
+	// environment must remember place of static data
+	UASSERT(obj->m_static_exists);
+	UASSERTEQ(auto, obj->m_static_block, testblockpos);
+
+#if 0
+	/*
+	 * FIXME: needs investigation
+	 * When using this code path the test fails and there's also a warning.
+	 * The problem is that the block is unloaded while the object is still in the
+	 * active list, removeFarObjects() has no chance at doing something.
+	 * This seems to be a general issue that in practice only applies with static_save=false.
+	 */
+	map.timerUpdate(10.0f, 5.0f, -1);
+	env->step(m_step_interval);
+#else
+	obj->markForRemoval();
+	env->step(m_step_interval);
+#endif
+
+	block = nullptr;
+	obj = nullptr;
+	UASSERT(!env->getActiveObject(obj_id));
+	// static data must have been deleted
+	block = map.emergeBlock(testblockpos, false);
+	if (block)
+		UASSERTEQ(size_t, block->m_static_objects.size(), 0);
+}
+
+void TestSAO::testStaticToTrue(ServerEnvironment *env)
+{
+	Map &map = env->getMap();
+
+	const v3f testpos(123 * BS, 5 * BS, 0);
+	const v3s16 testblockpos = getNodeBlockPos(floatToInt(testpos, BS));
+
+	auto obj = add_entity(env, testpos, "test:non_static");
+	UASSERT(obj);
+	const u16 obj_id = obj->getId();
+
+	UASSERT(!obj->m_static_exists);
+	obj->accessObjectProperties()->static_save = true;
+
+	env->step(m_step_interval);
+
+	obj = nullptr;
+	UASSERT(!env->getActiveObject(obj_id));
+
+	// data must have been newly saved
+	auto *block = map.getBlockNoCreateNoEx(testblockpos);
+	UASSERT(block);
+	UASSERTEQ(size_t, block->m_static_objects.getStoredSize(), 1);
+	UASSERTEQ(size_t, block->m_static_objects.getActiveSize(), 0);
+}