Re: [PATCH v3 3/3] cat-file: add "--literally" option

[karthik nayak <karthik.188@gmail.com>]

On 03/09/2015 04:20 AM, Eric Sunshine wrote:
> On Thu, Mar 5, 2015 at 1:19 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> made changes to "cat-file" to include a "--literally"
>
> Write in imperative mood: "Teach cat-file a --literally option..."
>
>> option which prints the type of the object without any
>> complaints.
>
> Unfortunately, this explanation is quite lacking. What "complaints"?
> What problem is --literally trying to solve? To answer these
> questions, you will probably want to say something about the sort of
> object which requires --literally, and how cat-file fails or behaves
> without it.
>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>> diff --git a/builtin/cat-file.c b/builtin/cat-file.c
>> index df99df4..60b9ec4 100644
>> --- a/builtin/cat-file.c
>> +++ b/builtin/cat-file.c
>> @@ -323,7 +332,7 @@ static int batch_objects(struct batch_options *opt)
>>   }
>>
>>   static const char * const cat_file_usage[] = {
>> -       N_("git cat-file (-t | -s | -e | -p | <type> | --textconv) <object>"),
>> +       N_("git cat-file (-t|-s|-e|-p|<type>|--textconv|-t --literally) <object>"),
>
> This might read more naturally as:
>
>      git cat-file (-t [--literally] | -s | -e | -p | <type> |
> --textconv) <object>
>
> rather than repeating the -t option.
>
>>          N_("git cat-file (--batch | --batch-check) < <list-of-objects>"),
>>          NULL
>>   };
>> @@ -369,6 +379,8 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
>>                  OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
>>                  OPT_SET_INT(0, "textconv", &opt,
>>                              N_("for blob objects, run textconv on object's content"), 'c'),
>> +               OPT_BOOL( 0, "literally", &literally,
>> +                         N_("show the type of the given loose object, use for debugging")),
>
> Taking other help strings into account, there is no need for the
> long-winded "type of the given loose object" when "loose object's
> type" will suffice. More importantly, thought, you should try to say
> something about how --literally is actually useful, such as for
> "broken" objects or objects not of a known type.
>
>>                  { OPTION_CALLBACK, 0, "batch", &batch, "format",
>>                          N_("show info and content of objects fed from the standard input"),
>>                          PARSE_OPT_OPTARG, batch_option_callback },
>> @@ -380,7 +392,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
>>
>>          git_config(git_cat_file_config, NULL);
>>
>> -       if (argc != 3 && argc != 2)
>> +       if (argc != 3 && argc != 2 && argc != 4)
>
> Perhaps it's time to rephrase this as "if (argc < 2 || argc > 4)"?
>
>>                  usage_with_options(cat_file_usage, options);
>>
>>          argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
>> @@ -405,5 +417,10 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
>>          if (batch.enabled)
>>                  return batch_objects(&batch);
>>
>> -       return cat_one_file(opt, exp_type, obj_name);
>> +       if (literally && opt == 't')
>> +               return cat_one_file(opt, exp_type, obj_name, literally);
>> +       else if (literally)
>> +               usage_with_options(cat_file_usage, options);
>
> I realize that existing cases in cat-file are already guilty of this
> transgression, but it is quite annoying when a program merely spits
> out its usage statement without actually telling you what you did
> wrong; and it's often difficult to figure out why it was rejected. It
> would be much more helpful in a case like this to state explicitly
> that --literally was given without -t. (But perhaps such a
> "friendliness" change is fodder for a separate patch.)
>
>> +
>> +       return cat_one_file(opt, exp_type, obj_name, literally);
>>   }
>> --
>> 2.3.1.167.g7f4ba4b.dirty

Thanks for the feedback.
Will fix everything you stated in the next patch.