Re: merginfo corruption?

On Thu, Oct 27, 2016 at 12:14 PM, Peter van Hoof <p.vanhoof_at_oma.be> wrote:
> Hi,
>
> Recently we have been having multiple instances of a problem that doesn't
> seem to be going away. The easiest way to see it is to reproduce the
> following steps.
>
> 1) check out a working copy of one of our development branches:
>
> svn co svn://svn.nublado.org/cloudy/branches/backtrace
>
> Changes from the trunk were last merged to this branch in r11144. This
> checkout looks fine and I want to merge the more recent changes from the
> trunk. So cd into it and proceed.
>
> 2) First take a look at which revisions are eligible:
>
> svn mergeinfo --show-revs eligible ^/trunk .
> r11156
> r11159
> r11160
> r11165
> r11166
> r11167
> [ snip... ]
> r11337
> r11338
> r11339
> r11340
> r11341
>
> This all looks very plausible. The first commit to the trunk after r11144 is
> r11156 and the last is r11341. All numbers shown above are correct. I didn't
> check all the numbers I cut out, but I assume they are correct as well.
>
> 3) All looks fine, so do the merge:
>
> svn merge ^/trunk .
> --- Merging r8669 into 'source':
> C source/rt_continuum_shield_fcn.cpp
> --- Recording mergeinfo for merge of r8667 through r8669 into '.':
> U .
> --- Recording mergeinfo for merge of r8667 through r8669 into 'source':
> U source
> Summary of conflicts:
> Text conflicts: 1
> Conflict discovered in file 'source/rt_continuum_shield_fcn.cpp'.
> Select: (p) postpone, (df) show diff, (e) edit file, (m) merge,
> (mc) my side of conflict, (tc) their side of conflict,
> (s) show all options: ^CSummary of conflicts:
> Text conflicts: 1
> svn: E155027: Unable to resolve conflicts on
> '/home/pvh/noot/backtrace/source/rt_continuum_shield_fcn.cpp'
>
> I hit ^C here. So all of a sudden svn wants to merge r8669, even though it
> was not marked as eligible before (and was already merged a long time
> ago)...
>
> So what is this? Corrupted information in the svn:mergeinfo propety? A bug
> in svn? Or both?

Maybe your branch wasn't really fully synced with ^/trunk up to
r11144, or at least not all mergeinfo related to this sync was fully
committed. I would guess that svn is trying to merge r8669 into
'source', because 'source' has "subtree mergeinfo", and someone didn't
commit the mergeinfo-modification on 'source', way back when he merged
r8669.

Further down in your output below, I can see that 'source' actually
has subtree mergeinfo (because svn records it there). And as you
probably know: once you have subtree mergeinfo, it *always* has to be
kept up to date (further merges to the parent will automatically
modify any subtree mergeinfo below -- those property mods have to be
committed or mergeinfo will be wrong). So maybe someone forgot to
commit the property modification on 'source' when he merged r8669. You
can probably verify this by checking the exact svn:mergeinfo property
on 'source' (with 'svn propget svn:mergeinfo').

> And more importantly how do I fix this? I tried doing this brute-force
> approach

Okay, seems like a good technique to fix this, but ...

> svn revert -R .
>
> svn merge --record-only -r1:11144 ^/trunk .
> --- Merging r2 through r11144 into '.':
> G tsuite/auto
> G tsuite
> G .
> --- Recording mergeinfo for merge of r2 through r11144 into '.':
> U .
> --- Recording mergeinfo for merge of r2 through r11144 into
> 'data/lamda/masterlist/Lamda.ini':
> U data/lamda/masterlist/Lamda.ini
> --- Recording mergeinfo for merge of r2 through r11144 into
> 'data/stout/zn/zn_19/zn_19.coll':
> U data/stout/zn/zn_19/zn_19.coll
> --- Eliding mergeinfo from 'data/stout/zn/zn_19/zn_19.coll':
> U data/stout/zn/zn_19/zn_19.coll
> --- Recording mergeinfo for merge of r2 through r11144 into
> 'data/stout/zn/zn_19/zn_19.nrg':
> U data/stout/zn/zn_19/zn_19.nrg
> --- Eliding mergeinfo from 'data/stout/zn/zn_19/zn_19.nrg':
> U data/stout/zn/zn_19/zn_19.nrg
> --- Recording mergeinfo for merge of r2 through r11144 into
> 'data/stout/zn/zn_19/zn_19.tp':
> U data/stout/zn/zn_19/zn_19.tp
> --- Eliding mergeinfo from 'data/stout/zn/zn_19/zn_19.tp':
> U data/stout/zn/zn_19/zn_19.tp
> --- Recording mergeinfo for merge of r2 through r11144 into 'source':
> U source
> --- Recording mergeinfo for merge of r2 through r11144 into 'tsuite':
> U tsuite
> --- Recording mergeinfo for merge of r2 through r11144 into 'tsuite/auto':
> U tsuite/auto
> --- Recording mergeinfo for merge of r2 through r11144 into
> 'tsuite/auto/chianti_all_cool.dat':
> U tsuite/auto/chianti_all_cool.dat
> --- Recording mergeinfo for merge of r2 through r11144 into
> 'tsuite/auto/chianti_all_cool.in':
> U tsuite/auto/chianti_all_cool.in

Here you should probably perform a commit ("Fixing merginfo of
previous merges" or something like that). Note the lines "Eliding
mergeinfo from 'data/stout/zn/zn_19/zn_19.coll'" and other "Eliding"
lines. This means svn removes subtree mergeinfo there, because it's
redundant (it's the same as what the parent directory says).

But you leave those property modifications as local mods without
committing, which I think lead to the next problem.

> svn merge ^/trunk .
> --- Merging r11145 through r11342 into '.':
> U data/chianti/masterlist/CloudyChianti.ini
> G data/lamda/masterlist/Lamda.ini
> U data/stout/c/c_3/c_3.coll
> [ snip... ]
> C data/stout/zn/zn_19/zn_19.coll
> C data/stout/zn/zn_19/zn_19.nrg
> C data/stout/zn/zn_19/zn_19.tp
> [ snip... ]
> G tsuite
> G .
> --- Recording mergeinfo for merge of r11145 through r11342 into '.':
> G .
> --- Recording mergeinfo for merge of r11145 through r11342 into
> 'data/lamda/masterlist/Lamda.ini':
> G data/lamda/masterlist/Lamda.ini
> --- Recording mergeinfo for merge of r11145 through r11342 into 'source':
> G source
> --- Recording mergeinfo for merge of r11145 through r11342 into 'tsuite':
> G tsuite
> --- Recording mergeinfo for merge of r11145 through r11342 into
> 'tsuite/auto':
> G tsuite/auto
> --- Recording mergeinfo for merge of r11145 through r11342 into
> 'tsuite/auto/chianti_all_cool.dat':
> G tsuite/auto/chianti_all_cool.dat
> --- Recording mergeinfo for merge of r11145 through r11342 into
> 'tsuite/auto/chianti_all_cool.in':
> G tsuite/auto/chianti_all_cool.in
> Summary of conflicts:
> Property conflicts: 3
> Conflict for property 'svn:mergeinfo' discovered on
> 'data/stout/zn/zn_19/zn_19.coll'.
> local delete, incoming edit upon merge
> Select: (p) postpone, (mf) my version, (tf) their version,
> (dc) display conflict, (e) edit property, (q) quit resolution,
> (h) help:
>
> Here I hit ^C again. So this starts promising enough, but then I am faced
> with a conflict in the svn:mergeinfo property and I have no idea how to
> resolve that.

So, that's a property modification coming in on the node where your
previous step just removed (elided) the mergeinfo. I'm not 100% sure,
but I'd try to commit the previous step first, and then rerun that
last command. Hope that fixes it ...

> This kind of problem seems to be spreading to more and more development
> branches, so I am really keen on finding a definitive solution for this.
> This is starting to interfere quite seriously with our workflow. So any help
> is appreciated!

Maybe interesting for you:
https://svn.apache.org/repos/asf/subversion/trunk/tools/client-side/svn-mergeinfo-normalizer

This hasn't been released as part of any official svn release yet, but
it seems to work quite well for some people, and could surely use
additional testing :-) (see [1] for another thread mentioning this
tool).

[1] https://svn.haxx.se/users/archive-2016-06/0062.shtml

-- 
Johan