fix import other proto bug, without changing the xxx_pb variable

[lifelongchaser]

an error occurs when you want to use other message type from another proto file,

[string "protobuf.lua"]:363: attempt to index upvalue 'message_type' (a nil value)

e.g.
mail.proto:

    import "reward.proto";
    package mail;

    message Mail
    {
        optional uint32 id = 1;  
        optional reward.Reward reward = 2;
    }

reward.proto:

    package reward; 
    message Reward
    {
        optional uint32 money = 1;
    }

test.lua:

    -- sending --
    local sendMail = mail_pb.Mail()
    sendMail.id = 12
    local reward = sendMail.reward
    reward.money = 30
    printf(sendMail)

    -- receiving--
    local recvMail = mail_pb.Mail()
    recvMail:ParseFromString(sendMail:SerializeToString())
    printf(recvMail)

The same thing happens when using repeated instead of optional.

[string "containers.lua"]:27: attempt to call field '_concrete_class' (a nil value)

The reason is that mail_pb.lua generated by protoc-gen-lua doesn't consider the situation of other proto msg type. The message_type is nil.

some guy has fixed this bug by putting the REWARD table to XXX_pb variable. But I offer another method without changing XXX_pb.

you can choose whether is more fit considering your program structure.

Thank you for reading.

[kudoran]

This soluation leads to another bug. If there are a lot of messages or enums in proto file, it will create lots of local variables . More than 200 local variables in a chunk lead to lua error.

[mazexiang]

local player = player_pb.Player()
player.email="123456"
player.user.username = "mazexiang"
player.user.password="1004"

local msgdata = player:SerializeToString()
local msgplayer = player_pb.Player()
msgplayer:ParseFromString(msgdata)
print(msgplayer.user.username)

this is a example,and it work success