Re: [PATCH v11 06/13] ref-filter: add option to filter out tags, branches and remotes

From: Karthik Nayak <karthik.188@gmail.com>
Date: Aug 17, 2015, 14:46 UTC
Message-ID: <CAOLa=ZRqs4fWOn_5s18KbacYgV0ti5G1idXdEc4H5Hz0=p9UFA@mail.gmail.com>
In-Reply-To: <CAPig+cTZvSW8ZRLFLhmQTYBwotVjMWANZy0OAZHpA79vW8GfGQ@mail.gmail.com>

On Mon, Aug 17, 2015 at 10:12 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:

Show 40 quoted lines

> On Sat, Aug 15, 2015 at 2:00 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> Add a function called 'for_each_reftype_fullpath()' to refs.{c,h}
>> which iterates through each ref for the given path without trimming
>> the path and also accounting for broken refs, if mentioned.
>>
>> Add 'filter_ref_kind()' in ref-filter.c to check the kind of ref being
>> handled and return the kind to 'ref_filter_handler()', where we
>> discard refs which we do not need and assign the kind to needed refs.
>>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>> diff --git a/ref-filter.c b/ref-filter.c
>> index eac99d0..abcd235 100644
>> --- a/ref-filter.c
>> +++ b/ref-filter.c
>> @@ -1226,16 +1262,29 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
>>  {
>>         struct ref_filter_cbdata ref_cbdata;
>>         int ret = 0;
>> +       unsigned int broken = 0;
>>
>>         ref_cbdata.array = array;
>>         ref_cbdata.filter = filter;
>>
>>         /*  Simple per-ref filtering */
>> -       if (type & (FILTER_REFS_ALL | FILTER_REFS_INCLUDE_BROKEN))
>> -               ret = for_each_rawref(ref_filter_handler, &ref_cbdata);
>> -       else if (type & FILTER_REFS_ALL)
>> -               ret = for_each_ref(ref_filter_handler, &ref_cbdata);
>> -       else if (type)
>> +       if (type & FILTER_REFS_INCLUDE_BROKEN) {
>> +               type -= FILTER_REFS_INCLUDE_BROKEN;
>
> The above is a somewhat unusual way to say the more idiomatic:
>
>     type &= ~FILTER_REFS_INCLUDE_BROKEN;
>
> when dealing with bit flags. Is there precedence elsewhere in the
> project for choosing '-' over '~'?
>

I just preferred it this way, but will change it.

Show 19 quoted lines

>> +               broken = 1;
>> +       }
>> +
>> +       filter->kind = type;
>> +       if (type == FILTER_REFS_BRANCHES)
>> +               ret = for_each_reftype_fullpath(ref_filter_handler, "refs/heads/", broken, &ref_cbdata);
>> +       else if (type == FILTER_REFS_REMOTES)
>> +               ret = for_each_reftype_fullpath(ref_filter_handler, "refs/remotes/", broken, &ref_cbdata);
>> +       else if (type == FILTER_REFS_TAGS)
>> +               ret = for_each_reftype_fullpath(ref_filter_handler, "refs/tags/", broken, &ref_cbdata);
>> +       else if (type & FILTER_REFS_ALL) {
>> +          e      ret = for_each_reftype_fullpath(ref_filter_handler, "", broken, &ref_cbdata);
>
> These cases are all the same except for the (string) second argument,
> aren't they? This might be less noisy and easier to follow if you
> assign the appropriate string to a variable first, and then invoke
> for_each_reftype_fullpath() once with the string variable as an
> argument.
>

The problem is when we have FILTER_REFS_DETACHED_HEAD we need to call head_ref() after collecting all other refs, this is because in branch.c we need to print the detached head first, hence it's inserted to the end of the ref_array. Doing it the way you suggested would require to check FILTER_REFS_ALL again after the first time for setting the string variable. I'd find that a bit more confusing.

Show 42 quoted lines

>> +               if (type & FILTER_REFS_DETACHED_HEAD)
>> +                       head_ref(ref_filter_handler, &ref_cbdata);
>> +       } else
>>                 die("filter_refs: invalid type");
>>
>>         /*  Filters that need revision walking */
>> diff --git a/ref-filter.h b/ref-filter.h
>> index 144a633..64fedd3 100644
>> --- a/ref-filter.h
>> +++ b/ref-filter.h
>> @@ -14,8 +14,14 @@
>> -#define FILTER_REFS_INCLUDE_BROKEN 0x1
>> -#define FILTER_REFS_ALL 0x2
>> +#define FILTER_REFS_INCLUDE_BROKEN 0x0001
>> +#define FILTER_REFS_TAGS           0x0002
>> +#define FILTER_REFS_BRANCHES       0x0004
>> +#define FILTER_REFS_REMOTES        0x0008
>> +#define FILTER_REFS_OTHERS         0x0010
>> +#define FILTER_REFS_ALL            (FILTER_REFS_TAGS | FILTER_REFS_BRANCHES | \
>> +                                   FILTER_REFS_REMOTES | FILTER_REFS_OTHERS)
>> +#define FILTER_REFS_DETACHED_HEAD  0x0020
>
> I suppose there's some good reason that FILTER_REFS_DETACHED_HEAD is
> not a member of FILTER_REFS_ALL? Perhaps add a comment explaining it?
>
>> diff --git a/refs.c b/refs.c
>> index 2db2975..0f18c34 100644
>> --- a/refs.c
>> +++ b/refs.c
>> @@ -2145,6 +2145,13 @@ int for_each_replace_ref(each_ref_fn fn, void *cb_data)
>>                                strlen(git_replace_ref_base), 0, cb_data);
>>  }
>>
>> +int for_each_reftype_fullpath(each_ref_fn fn, char *type, unsigned int broken, void *cb_data)
>> +{
>> +       if (broken)
>> +               broken = DO_FOR_EACH_INCLUDE_BROKEN;
>
> It's a bit ugly and confusing to have the same variable, 'broken', act
> as both a boolean input argument and as a bit flag argument to the
> called function.
>

Ill change that :)

-- 
Regards,
Karthik Nayak