random order due to APR hash change (was: random sort of svn status and svn diff)

On 2012-03-21 00:51:53 +0000, Philip Martin wrote:
> Sérgio Basto <sergio_at_serjux.com> writes:
>
> > On Tue, 2012-03-20 at 19:23 -0500, Ryan Schmidt wrote:
> >> On Mar 20, 2012, at 19:17, Sérgio Basto wrote:
> >>
> >> > Hi, I am facing a problem
> >> > I do a svn diff | lsdiff
> >> > I got file in random order , also happens with svn status
> >>
> >> Correct, Subversion does not output these in a sorted order.
> >
> > but one month ago , svn diff have always same output , now it is
> > random , is a bug or regression.
>
> That's the result of a change in the APR hash table implementation.
> Subversion often uses "hash order" and in the past this was always the
> same for a given set of hash keys. The new APR implementation means
> that this order is no longer constant.

In Subversion 1.6.x under Debian, it also affects the properties order
in "svn dump": http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=664867
I don't know about Subversion 1.7.x.

As I've said in my bug report:

----------------------------------------

After the upgrade to libapr1 1.4.6-1, the properties in the "svn dump"
output are now in a random order. I don't think their order is
specified, but IMHO, they should be in a consistent order to allow
conventional tools like diff, MD5 checking on a dump, rsync[*] and
so on to work nicely.

[*] rsync will still work, but obviously less efficiently.

----------------------------------------

I had to revert to the previous libapr1 version.

> > why the output shouldn't be sorted by name or something else ?
> > or why svn don't have a sort option this is insane .
>
> It could be done but nobody has done it yet, the APR change is only a
> few weeks old. Sorting may need to be optional as there is a cost to
> sorting that not everybody would want.

Is this cost noticeable (when done efficiently)?

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