bug#28570: 27.0.50; [PATCH] Disable unhelpful default Extra: header in vc-dir

[Göktuğ Kayaalp]

On 2017-09-25 03:24 +03, Dmitry Gutov <dgutov@yandex.ru> wrote:
> On 9/23/17 6:39 PM, Göktuğ Kayaalp wrote:
>>
>> The function ‘vc-default-dir-extra-headers’ is implemented as a stub
>> function that prints in the vc-dir buffer a rather annoying and
>> unhelpful message advicing that the implementer of a VC backend should
>> create some backend specific headers and that doing this is easy.
>> vc-rcs doesn't implement any (and I doubt it needs), and thus whenever I
>> use vc-dir on an RCS repository, this message is shown.  Attached is a
>> patch that disables this behaviour by making the said function return
>> nil instead (the function as it is includes a comment that says to do so
>> before the ‘release’).
>
> Instead of changing the default, how about we create a RCS-specific
> implementation that does nothing? Because it doesn't need to.
>

Hi, please find attached the patch I promised some time ago.  Sorry for
the latency.

-- 
İ. Göktuğ Kayaalp       <http://www.gkayaalp.com/>
                        024C 30DD 597D 142B 49AC
                        40EB 465C D949 B101 2427

diff --git a/lisp/vc/vc-rcs.el b/lisp/vc/vc-rcs.el
index 9dffc144c6..0a10449763 100644
--- a/lisp/vc/vc-rcs.el
+++ b/lisp/vc/vc-rcs.el
@@ -177,6 +177,8 @@ vc-rcs-dir-status-files
          (push (list frel state) result))))
     (funcall update-function result)))
 
+(defun vc-rcs-dir-extra-headers (&rest ignore))
+
 (defun vc-rcs-working-revision (file)
   "RCS-specific version of `vc-working-revision'."
   (or (and vc-consult-headers