Re: vc-region-history: HG?

[Richard Copley <rcopley@gmail.com>]

On 16 January 2018 at 21:04, Óscar Fuentes <ofv@wanadoo.es> wrote:
> Richard Copley <rcopley@gmail.com> writes:
>
>> On 16 January 2018 at 18:41, Óscar Fuentes <ofv@wanadoo.es> wrote:
>>> Uwe Brauer <oub@mat.ucm.es> writes:
>>>
>>>> But, what is the underlying git command? I tried to debug the function
>>>> and couldn't figure it out.
>>
>> Uwe,
>>
>> To see the backend command, set 'vc-command-messages' to t
>> before issuing a VC command in Emacs.
>>
>> For vc-command history the messages logged are:
>>
>> Running git --no-pager diff-index --exit-code -p HEAD  -- Makefile.in
>> in foreground...
>> Running git --no-pager diff-index --exit-code -p HEAD  -- Makefile.in...OK = 0
>> Running git --no-pager log -p -L... . in background... done
>>
>> In this case I'm not sure that tells the whole story and I expect Emacs does
>> some of the work. I didn't put much effort into understanding the output but
>> perhaps it will give you a useful hint.
>>
>>> From vc-git-region-history:
>>>
>>> (vc-git-command buffer 'async nil "log" "-p" ;"--follow" ;FIXME: not supported?
>>>                 (format "-L%d,%d:%s" lfrom lto (file-relative-name file)))
>>>
>>>
>>> lfrom and lto are line numbers.
>
> In case it is not clear, the command is
>
> git log -p -L10,20:foo.c
>
> for printing the history of lines 10 to 20 of file foo.c

Oh. I think it's a shame that vc-command-messages doesn't tell the whole ... .