update non-reset-packs semantics

src/logic/scripting/lua/lua_util.cpp

@@ -336,6 +336,22 @@ int lua::create_environment(State* L, int parent) {
     return id;
 }
 
+int lua::restore_pack_environment(lua::State* L, const std::string& packid) {
+    if(!lua::getglobal(L, "__vc__pack_envs")) {
+        return -1;
+    }
+    int id = nextEnvironment++;
+
+    if (lua::getfield(L, packid)) {
+        // envname = env
+        setglobal(L, env_name(id));
+        lua::pop(L);
+        return id;
+    }
+    lua::pop(L);
+    return -1;
+}
+
 void lua::remove_environment(State* L, int id) {
     if (id == 0) {
         return;

src/logic/scripting/lua/lua_util.hpp

@@ -614,6 +614,7 @@ namespace lua {
         return 0;
     }
     int create_environment(lua::State*, int parent);
+    int restore_pack_environment(lua::State*, const std::string& packid);
     void remove_environment(lua::State*, int id);
 
     inline void close(lua::State* L) {

src/logic/scripting/scripting.cpp

@@ -173,7 +173,15 @@ std::unique_ptr<Process> scripting::start_app_script(const io::path& script) {
     const ContentPack& pack
 ) {
     auto L = lua::get_main_state();
-    int id = lua::create_environment(L, 0);
+    int id = lua::restore_pack_environment(L, pack.id);
+    if (id != -1) {
+        return std::shared_ptr<int>(new int(id), [=](int* id) { //-V508
+            lua::remove_environment(L, *id);
+            delete id;
+        });
+    }
+    id = lua::create_environment(L, 0);
+
     lua::pushenv(L, id);
     lua::pushvalue(L, -1);
     lua::setfield(L, "PACK_ENV");
@@ -352,9 +360,6 @@ void scripting::cleanup(const std::vector<std::string>& nonReset) {
     auto L = lua::get_main_state();
     lua::requireglobal(L, "pack");
     for (auto& pack : content_control->getAllContentPacks()) {
-        if (std::find(nonReset.begin(), nonReset.end(), pack.id) != nonReset.end()) {
-            continue;
-        }
         lua::requirefield(L, "unload");
         lua::pushstring(L, pack.id);
         lua::call_nothrow(L, 1);