Re: [PATCH 02/15] for-each-ref: don't print out elements directly

> Ramkumar Ramachandra <artagnon@gmail.com> writes:
>
>> From: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
>>
>> Currently, the entire callchain starting from show_ref() parses and
>> prints immediately.  This inflexibility limits our ability to extend the
>> parser.  So, convert the entire callchain to accept a strbuf argument to
>> write to.  Also introduce a show_refs() helper that calls show_ref() in
>> a loop to avoid cluttering up cmd_for_each_ref() with the task of
>> initializing/freeing the strbuf.
>>
>> [rr: commit message]
>>
>> Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
>> ---
>>  builtin/for-each-ref.c | 55 ++++++++++++++++++++++++++++++++------------------
>>  1 file changed, 35 insertions(+), 20 deletions(-)
>>
>> diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
>> index 1d4083c..e2d6c5a 100644
>> --- a/builtin/for-each-ref.c
>> +++ b/builtin/for-each-ref.c
>> @@ -864,31 +864,31 @@ static void sort_refs(struct ref_sort *sort, struct refinfo **refs, int num_refs
>>       qsort(refs, num_refs, sizeof(struct refinfo *), compare_refs);
>>  }
>>
>> -static void print_value(struct refinfo *ref, int atom, int quote_style)
>> +static void print_value(struct strbuf *sb, struct refinfo *ref,
>> +                     int atom, int quote_style)
>>  {
>>       struct atom_value *v;
>> -     struct strbuf sb = STRBUF_INIT;
>>       get_value(ref, atom, &v);
>>       switch (quote_style) {
>>       case QUOTE_NONE:
>> -             fputs(v->s, stdout);
>> +             strbuf_addstr(sb, v->s);
>>               break;
>>       case QUOTE_SHELL:
>> -             sq_quote_buf(&sb, v->s);
>> +             sq_quote_buf(sb, v->s);
>>               break;
>>       case QUOTE_PERL:
>> -             perl_quote_buf(&sb, v->s);
>> +             perl_quote_buf(sb, v->s);
>>               break;
>>       case QUOTE_PYTHON:
>> -             python_quote_buf(&sb, v->s);
>> +             python_quote_buf(sb, v->s);
>>               break;
>>       case QUOTE_TCL:
>> -             tcl_quote_buf(&sb, v->s);
>> +             tcl_quote_buf(sb, v->s);
>>               break;
>>       }
>>       if (quote_style != QUOTE_NONE) {
>> -             fputs(sb.buf, stdout);
>> -             strbuf_release(&sb);
>> +             fputs(sb->buf, stdout);
>> +             strbuf_release(sb);
>>       }
>>  }
>
> The change in the first step made some sense; if asked not to quote,
> it just emits the atom with fputs() in the switch (quote_style), so
> there is nothing more to do after the switch.
>
> But this change cannot be correct.  It prints literally to sb, and
> leaves the function without emitting anything nor freeing the
> resource in sb.