Re: [Tarantool-patches] [PATCH v2 1/2] uuid: support comparison of uuid values in Lua

[Vladislav Shpilevoy <v.shpilevoy@tarantool.org>]

Hi! Thanks for the fixes!

> diff --git a/src/lua/uuid.lua b/src/lua/uuid.lua
> index 08991cfeb..275f4e5c5 100644
> --- a/src/lua/uuid.lua
> +++ b/src/lua/uuid.lua
> @@ -93,13 +93,20 @@ local uuid_isnil = function(uu)
>      return builtin.tt_uuid_is_nil(uu)
>  end
> 
> +local check_uuid = function(value, index)
> +    if is_uuid(value) then
> +        return value
> +    end
> +
> +    local err_fmt = 'incorrect value to compare with uuid as %d argument'
> +    error(err_fmt:format(index), 4)
> +end
> +
>  local uuid_eq = function(lhs, rhs)
>      if not is_uuid(rhs) then
>          return false
>      end
> -    if not is_uuid(lhs) then
> -        return error('Usage: uuid == var')
> -    end
> +    lhs = check_uuid(lhs, 1)

Check_uuid() here uses incorrect error index. check_uuid()
raises error(..., 4). So check_uuid() itself is level 1.
uuid_eq() is level 2. And the calling code is level 3. You
will raise one level beyond the caller code.

For uuid_lt and uuid_le it works, because check_uuid() is
level 1, uuid_cmp() is level 2, uuid_lt/le() is level 3, and
the calling code is level 4.

But I can't give you a test, since I have no idea how to provide
lhs with non-uuid type. Igor said we can give metatable of uuid to
some non-uuid value, but I failed to assign uuid metatable to
anything else.

After you fix this (but I don't insist on adding a test, because
I don't know how), I suggest you to get a second review from Igor.