Re: Svn mergeinfo appearing on sub-directories

On Thu, Jun 9, 2011 at 1:18 PM, Echlin, Jamie
<jamie.echlin_at_credit-suisse.com> wrote:
> Further information on this... it's definitely not related to the authz
> as the same behaviour happens when using the file: protocol. It appears
> to be to do with the mergeinfo that's already present, as if I delete it
> all then it works as expected.
>
> When doing a merge, is the mergeinfo anywhere other than the source and
> target trees taken into account somehow?
>
> Failing all else my next step will be to attempt to debug with svnkit,
> as I don't know C very well.
>
> Cheers, jamie
>
> Morning,
>
> Recently, when any user merges up from trunk to their topic branch, svn
> appears to do it directory by directory for immediate sub-directories of
> the branch root, so each sub-directory gets explicit mergeinfo.
>
> [X:\XYZ.11650]svn merge http://svn.example.net/ABCD/Source/trunk
> --- Merging r38851 through r39538 into 'Automation':
> U    Automation\TestingDashboard\TestingDashboard.sln
> ...
> --- Merging r38851 through r39541 into 'Tools':
> ...
>
> Up to around 6 months ago this would not have been noticed, however we
> have had so many problems with mergeinfo that there is now a hook that
> prevents mergeinfo going anywhere other than the "branch" roots. The
> hook is working fine, the problem is that svn is doing this, when there
> seems to be no apparent reason.
>
> I understand that this would happen if the user did not have read access
> to one of the sub-directories in the source tree, but this is not the
> case. I have compared a svn ls -R using the file protocol with the same
> using the http protocol, just to be sure, and there is no difference.
>
> It could also happen if the target wc was not at infinite depth, but
> that's not the case either, nor switched sub-dirs, or anything similar.
>
> There is no sub-tree mergeinfo on the trunk.
>
> What other problem could be causing this?

Hi Jamie,

This is normal behavior of svn currently. Every subtree that already
has "explicit mergeinfo" (meaning it has its own svn:mergeinfo
property) will have that mergeinfo updated on every subsequent merge.
That is done because it needs to be kept up to date.

If a node doesn't have mergeinfo of its own, it inherits it from its
parent directory. But from the moment it has explicit mergeinfo of its
own, it no longer inherits anything, and so the property needs to be
kept up to date all the time. Even if that subtree is totally not
affected by the merge. See [1] for more in-depth info.

I know this can be confusing/annoying. The upcoming 1.7 release should
normally improve this situation, because it will only update the
mergeinfo on those subtrees that are affected by the merge.

HTH,

-- 
Johan
[1] http://www.collab.net/community/subversion/articles/merge-info.html
(a huge article, but it contains a lot of useful information if you
want to understand how mergeinfo works)