"Yi Yue" <include_yy@qq.com> writes:

>> (unrelated, but why do your messages include HTML entities?) 
>
> (Sorry, I forgot to forbid the default formatter of my email client.)

it appears more or less correctly when I view the HTML message, so don't
worry.

>> My main fear is that this might have some unintended consequences. 
>
> Of course. 
>
>> I wouldn't want to rely on my understanding of vc either. While it 
>> would be easy to add a dynamic variable to indicate this behaviour, I am 
>> careful not to overburden the abstractions that VC provides. 
>
> Understand. 
>
> I read the docstring of `vc-pull', which is used by `package-vc-upgrade'. 
> It says: 
>
> -------------------------------------------------------------------------- 
> "Update the current fileset or branch. 
> You must be visiting a version controlled file, or in a `vc-dir' buffer. 
> ..."
> -------------------------------------------------------------------------- 
>
> But `vc-dir' is a user command other than a function, it will open a new buffer and return nil. 
> In consideration of the fact that `vc-pull' is an async function, it is not easy for us to 
> kill the `vc-diff' buffer right after the pull operation. 

This actually gives us another possibility how to tackle the issue: