[Tarantool-patches] [PATCH 3/9] error: move code to struct error from ClientError

[Vladislav Shpilevoy]

Thanks for the review!

>> diff --git a/src/lua/error.lua b/src/lua/error.lua
>> index ebc784f07..9fb227df4 100644
>> --- a/src/lua/error.lua
>> +++ b/src/lua/error.lua
>> @@ -18,6 +18,7 @@ struct error {
>>       const struct type_info *_type;
>>       int64_t _refs;
>>       int _saved_errno;
>> +    int code;
> 
> 1. All the other fields are prefixed with "_" for some reason.
>    Let's do the same for "code", just to comply.

I named it without '_' intentionally. Because then Lua will see
this field right away when you do `err.code`. That also allows
me not to define a getter in `error_fields` table.

>>       /** Line number. */
>>       unsigned _line;
>>       /* Source file name. */
>> @@ -158,7 +159,7 @@ local function error_unpack(err)
>>       if not ffi.istype('struct error', err) then
>>           error("Usage: error:unpack()")
>>       end
>> -    local result = {}
>> +    local result = {code = err.code}
> 
> 2. Why not add 'code' to 'error_fields' ?

Because it is visible without a getter anyway. On the downside, here
in unpack() I need to add it explicitly.