bug#50340: Fix remote-location in vc-git-log-incoming

[Dmitry Gutov <dgutov@yandex.ru>]

On 03.09.2021 11:12, Juri Linkov wrote:
>>> -  (vc-git-command nil 0 nil "fetch")
>>> +  (vc-git-command nil 0 nil "fetch" (unless (string= remote-location "")
>>> +                                      remote-location))
>>
>> I'm not sure which scenario this fixes (pressing RET after 'C-u C-x v I'
>> works fine here), but it shouldn't hurt either.
> 
> It fixes the scenario with a non-default remote.  Could you try 'C-u C-x v I'
> and typing the name of a non-default remote in a repo with two remotes?
> I wonder if it already worked, and maybe I have some misconfiguration.

Ah, I see what you are referring to.

But does the feature work then?

With your patch, I can pass some alternative upstream to the command, 
and it fails at the end with something like:

fatal: ambiguous argument 'HEAD..upstream': unknown revision or path not 
in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

>> So if you have a stable repro (some alternative completing-read-function?),
>> you can go ahead and install.
> 
> Regarding the default completing-read-function, the prompt of 'C-u C-x v I'
> doesn't provide completion on remote names.  Maybe this should be improved
> as well.

I guess some new backend action ('remote-locations'?) could help with that.