Hello,

On Mon 07 Jul 2025 at 11:09pm +02, Jakub Ječmínek via "Bug reports for GNU Emacs, the Swiss army knife of text editors" wrote:

> On 7/7/25 10:34, Sean Whitton wrote:
>> That's okay, I think the only thing is to check that the backend
>> implements file-name-changes using vc-find-backend-function.  Then so
>> long as the general approach makes sense and works for Git it's fine.
>
> I've updated the patch based on your suggestions. You're right, `vc-annotate'
> is indeed a better place for this change.

Jakub, I'm attaching a version of your patch with a rewritten commit
message to more closely match our conventions, and to avoid overlong
lines of code.  Please take a look.

>>> Dmitry Gutov <dgutov@yandex.ru> writes:
>>>
>>>> On 05/07/2025 19:42, Sean Whitton wrote:
>>>> I think (?) the file name might have changed in some later revision - so
>>>> it won't be returned by vc-git-file-name-changes for that specific REV,
>>>> but still might not match the current name.
>>>
>>> I'm not sure.
>> Seems like this needs to be investigated before we can proceed.
> I've tested various scenarios and haven't encountered any issues with the
> current implementation. It would be great if you could test the change as
> well, in case there are edge cases I missed.

I think that we need to see an argument in terms of the definition of
the file-name-changes backend function that demonstrates that your
approach will always work:

;;   Return the list of pairs with changes in file names in REV.  When
;;   a file was added, it should be a cons with nil car.  When
;;   deleted, a cons with nil cdr.  When copied or renamed, a cons
;;   with the source name as car and destination name as cdr.

-- 
Sean Whitton