check is_iterator_dirty for Group.Next

group.h

@@ -23,6 +23,7 @@ public:
 	card_set::iterator it;
 	int32 ref_handle{ 0 };
 	uint32 is_readonly{ 0 };
+	bool is_iterator_dirty{ true };
 	
 	inline bool has_card(card* c) {
 		return container.find(c) != container.end();

libgroup.cpp

@@ -46,6 +46,7 @@ int32 scriptlib::group_delete(lua_State *L) {
 	group* pgroup = *(group**) lua_touserdata(L, 1);
 	if(pgroup->is_readonly != 2)
 		return 0;
+	pgroup->is_iterator_dirty = true;
 	pgroup->is_readonly = 0;
 	pduel->sgroups.insert(pgroup);
 	return 0;
@@ -66,6 +67,7 @@ int32 scriptlib::group_clear(lua_State *L) {
 	check_param(L, PARAM_TYPE_GROUP, 1);
 	group* pgroup = *(group**) lua_touserdata(L, 1);
 	if (pgroup->is_readonly != 1) {
+		pgroup->is_iterator_dirty = true;
 		pgroup->container.clear();
 	}
 	return 0;
@@ -77,6 +79,7 @@ int32 scriptlib::group_add_card(lua_State *L) {
 	group* pgroup = *(group**) lua_touserdata(L, 1);
 	card* pcard = *(card**) lua_touserdata(L, 2);
 	if (pgroup->is_readonly != 1) {
+		pgroup->is_iterator_dirty = true;
 		pgroup->container.insert(pcard);
 	}
 	return 0;
@@ -88,6 +91,7 @@ int32 scriptlib::group_remove_card(lua_State *L) {
 	group* pgroup = *(group**) lua_touserdata(L, 1);
 	card* pcard = *(card**) lua_touserdata(L, 2);
 	if (pgroup->is_readonly != 1) {
+		pgroup->is_iterator_dirty = true;
 		pgroup->container.erase(pcard);
 	}
 	return 0;
@@ -96,6 +100,9 @@ int32 scriptlib::group_get_next(lua_State *L) {
 	check_param_count(L, 1);
 	check_param(L, PARAM_TYPE_GROUP, 1);
 	group* pgroup = *(group**) lua_touserdata(L, 1);
+	if (pgroup->is_iterator_dirty) {
+		return luaL_error(L, "Called Group.GetNext without calling Group.GetFirst first.");
+	}
 	if(pgroup->it == pgroup->container.end())
 		lua_pushnil(L);
 	else {
@@ -111,6 +118,7 @@ int32 scriptlib::group_get_first(lua_State *L) {
 	check_param_count(L, 1);
 	check_param(L, PARAM_TYPE_GROUP, 1);
 	group* pgroup = *(group**) lua_touserdata(L, 1);
+	pgroup->is_iterator_dirty = false;
 	if (pgroup->container.size()) {
 		pgroup->it = pgroup->container.begin();
 		interpreter::card2value(L, (*(pgroup->it)));
@@ -637,6 +645,7 @@ int32 scriptlib::group_remove(lua_State *L) {
 	uint32 extraargs = lua_gettop(L) - 3;
 	if(pgroup->is_readonly == 1)
 		return 0;
+	pgroup->is_iterator_dirty = true;
 	for (auto cit = pgroup->container.begin(); cit != pgroup->container.end();) {
 		if((*cit) != pexception && pduel->lua->check_matching(*cit, 2, extraargs)) {
 			cit = pgroup->container.erase(cit);
@@ -644,7 +653,6 @@ int32 scriptlib::group_remove(lua_State *L) {
 		else
 			++cit;
 	}
-	pgroup->it = pgroup->container.begin();
 	return 0;
 }
 int32 scriptlib::group_merge(lua_State *L) {
@@ -655,6 +663,7 @@ int32 scriptlib::group_merge(lua_State *L) {
 	group* mgroup = *(group**) lua_touserdata(L, 2);
 	if(pgroup->is_readonly == 1)
 		return 0;
+	pgroup->is_iterator_dirty = true;
 	pgroup->container.insert(mgroup->container.begin(), mgroup->container.end());
 	return 0;
 }
@@ -666,6 +675,7 @@ int32 scriptlib::group_sub(lua_State *L) {
 	group* sgroup = *(group**) lua_touserdata(L, 2);
 	if(pgroup->is_readonly == 1)
 		return 0;
+	pgroup->is_iterator_dirty = true;
 	for (auto& pcard : sgroup->container) {
 		pgroup->container.erase(pcard);
 	}