Function convert_to_exception

library/LuaTools.cpp:573–661

}

static bool convert_to_exception(lua_State *L, int slevel, lua_State *thread = NULL)
{
    if (!thread)
        thread = L;

    if (thread == L)
        lua_pushthread(L);
    else
    {
        lua_pushthread(thread);
        lua_xmove(thread, L, 1);
    }

    lua_swap(L);

    int base = lua_gettop(L);

    bool force_unknown = false;

    if (lua_istable(L, base) && lua_getmetatable(L, base))
    {
        lua_rawgetp(L, LUA_REGISTRYINDEX, &DFHACK_EXCEPTION_META_TOKEN);
        bool is_exception = lua_rawequal(L, -1, -2);
        lua_settop(L, base);

        if (is_exception)
        {
            // If it is an exception from the same thread, return as is
            lua_getfield(L, base, "thread");
            bool same_thread = lua_rawequal(L, -1, base-1);
            lua_settop(L, base);

            if (same_thread)
            {
                lua_remove(L, base-1);
                return false;
            }

            // Create a new exception for this thread
            lua_newtable(L);
            luaL_where(L, slevel);
            lua_setfield(L, -2, "where");
            lua_pushstring(L, "coroutine resume failed");
            lua_setfield(L, -2, "message");
            lua_getfield(L, -2, "verbose");
            lua_setfield(L, -2, "verbose");
            lua_swap(L);
            lua_setfield(L, -2, "cause");
        }
        else
            force_unknown = true;
    }

    // Promote non-table to table, and do some sanity checks
    if (!lua_istable(L, base) || force_unknown)
    {
        lua_newtable(L);
        lua_swap(L);