Re: [PATCH] diff: handle "-" as abbreviation of '@{-1}'

> dash is usually used for representing stdin / stdout as a file. I
> think this could drive to error... but I would agree with transforming
> -h1 to @{-1} or -h2 to @{-2} (-h representing head).
> 
> I do agree however that all those signs are thought with american
> keyboards in mind. All those punctuation marks are usually hard to
> type in other keyboards, and -h1 is way simpler than HEAD~ or @{-1}
> 
> This links provides an example of my worry:
> http://stackoverflow.com/questions/15270970/is-it-possible-to-git-diff-a-file-against-standard-input
> 
> On Sat, Mar 12, 2016 at 2:11 AM, Senorsen <senorsen.zhang@gmail.com> wrote:
>>
>> Currently it just replace "-" in argv[] into "@{-1}".
>>
>> For example,
>>
>>     git diff -
>>
>> equals to
>>
>>     git diff @{-1}
>>
>> Signed-off-by: Senorsen <senorsen.zhang@gmail.com>
>> ---
>> Notes:
>>     Hello everyone, I'm Zhang Sen, a college student from Zhejiang University
>>     in China, and this is a patch for the microproject of GSoC 2016. I'm
>>     looking forward to contributing to Git and participating in GSoC 2016.
>>
>>     I have learnt some rules and guides from the documents, and carefully
>>     wrote this small patch, according to other code from git.
>>
>>     Thanks a lot!
>>
>>  builtin/diff.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/builtin/diff.c b/builtin/diff.c
>> index 52c98a9..c110141 100644
>> --- a/builtin/diff.c
>> +++ b/builtin/diff.c
>> @@ -389,6 +389,11 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
>>                 }
>>         }
>>
>> +       for (i = 0; i < argc; i++) {
>> +               if (!strcmp(argv[i], "-"))
>> +                       argv[i] = "@{-1}";
>> +       }
>> +
>>         for (i = 0; i < rev.pending.nr; i++) {
>>                 struct object_array_entry *entry = &rev.pending.objects[i];
>>                 struct object *obj = entry->item;
>> --
>> 2.7.0
>>