Re: [PATCH v6 7/7] ref-filter.c: parse trailers arguments with %(contents) atom

>>  		atom->u.contents.option = C_SUB;
>> -	else if (!strcmp(arg, "trailers"))
>> -		atom->u.contents.option = C_TRAILERS;
>> -	else if (skip_prefix(arg, "lines=", &arg)) {
>> +	else if (skip_prefix(arg, "trailers", &arg)) {
>> +		skip_prefix(arg, ":", &arg);
>> +		trailers_atom_parser(format, atom, *arg ? NULL : arg);
>
> I think your logic is flipped. You want "*arg ? arg : NULL";