Oh and Stefan "Again, please verify that you're invoking the tool in the right way before jumping to conclusions."
Jumping to conclusions is the only way I get exercise :) :) On 9 December 2011 16:52, Rob Pointer <rpoin...@clearvision-cm.com> wrote: > Stefan > That's exactly what I was saying, that if any merging/copy has occurred > from trunk to branch, then you need to use the reintegrate merge. if you > don't then that's when you get merge conflicts. > > > On 9 December 2011 14:00, Stefan Sperling <s...@elego.de> wrote: > >> On Fri, Dec 09, 2011 at 01:05:02PM +0000, Rob Pointer wrote: >> > Mark >> > If you put changes multiple times from trunk to a branch (in development >> > terms, a re-base) you can cause reflective merges and actually cause >> more >> > problems. The recommended merge back into trunk is a reintegrate merge. >> > I am not sure if this has been addressed in 1.7, but certainly for >> earlier >> > versions (anyone please correct me if I am wrong here though :) ). >> > >> > The scenario goes >> > 1) trunk contains file A >> > 2) copy trunk to branch1 >> > 3) modify file A in branch1 >> > 4) add folderb/fileb in trunk >> > 5) branch (copy) folderb into branch (or merge if it actually works :) ) >> > 6) do some changes to file A and ffileb >> > 7) merge back into trunk. >> > >> > SVN seems to get confused and when it checks the history of both trunk >> and >> > branch1 it doesn't know that the folderb/fileb was added in branch1 >> using a >> > copy, therefore it just thinks you added the files on trunk and then >> > branch1 as two separate operations (for any clearcase users this is an >> evil >> > twin scenario). Therefore SVN will create a tree conflict when merging >> > your branch back into trunk. >> >> Wrong, wrong, wrong. You may believe that Subversion is broken but in >> fact you're just pushing its buttons the wrong way. >> >> To be clear, if you use the correct merge syntax for each step your >> scenario works just fine. And this applies to 1.6 as well as 1.7. >> >> To demonstrate: >> >> + rm -rf reflective-merge >> + mkdir -p reflective-merge >> + mkdir -p reflective-merge/trunk >> + echo A >> + > reflective-merge/trunk/A >> + svnadmin create /tmp/reflective-merge/repos >> + svn import reflective-merge/trunk >> file:////tmp/reflective-merge/repos/trunk -m importing project tree >> Adding reflective-merge/trunk/A >> >> Committed revision 1. >> + svn copy file:////tmp/reflective-merge/repos/trunk >> file:////tmp/reflective-merge/repos/branch1 -m creating branch >> >> Committed revision 2. >> + rm -rf reflective-merge/trunk >> + svn checkout file:////tmp/reflective-merge/repos/trunk >> reflective-merge/trunk >> A reflective-merge/trunk/A >> Checked out revision 2. >> + svn checkout file:////tmp/reflective-merge/repos/branch1 >> reflective-merge/branch1 >> A reflective-merge/branch1/A >> Checked out revision 2. >> + echo foo >> + >> reflective-merge/branch1/A >> + svn commit -m modify A on branch reflective-merge/branch1 >> Sending reflective-merge/branch1/A >> Transmitting file data . >> Committed revision 3. >> + svn mkdir reflective-merge/trunk/folderb >> A reflective-merge/trunk/folderb >> + echo bar >> + >> reflective-merge/trunk/folderb/fileb >> + svn commit -m add folderb/fileb on trunk reflective-merge/trunk >> Adding reflective-merge/trunk/folderb >> >> Committed revision 4. >> + svn update reflective-merge/branch1 >> Updating 'reflective-merge/branch1': >> At revision 4. >> + svn merge file:////tmp/reflective-merge/repos/trunk >> reflective-merge/branch1 --accept postpone >> --- Merging r2 through r4 into 'reflective-merge/branch1': >> A reflective-merge/branch1/folderb >> --- Recording mergeinfo for merge of r2 through r4 into >> 'reflective-merge/branch1': >> U reflective-merge/branch1 >> + svn commit reflective-merge/branch1 -m merge trunk into branch (no >> conflicts) >> Sending reflective-merge/branch1 >> Adding reflective-merge/branch1/folderb >> >> Committed revision 5. >> + echo baz >> + >> reflective-merge/branch1/folderb/fileb >> + svn commit -m modify folderb/fileb on branch reflective-merge/branch1 >> + svn update reflective-merge/trunk >> Updating 'reflective-merge/trunk': >> At revision 5. >> + svn merge --reintegrate file:////tmp/reflective-merge/repos/branch1 >> reflective-merge/trunk --accept postpone >> --- Merging differences between repository URLs into >> 'reflective-merge/trunk': >> U reflective-merge/trunk/A >> --- Recording mergeinfo for merge between repository URLs into >> 'reflective-merge/trunk': >> U reflective-merge/trunk >> + svn commit reflective-merge/trunk -m reintegrate branch into trunk (no >> conflicts) >> Sending reflective-merge/trunk >> Sending reflective-merge/trunk/A >> Transmitting file data . >> Committed revision 6. >> >> You only get a tree-conflict if you forget to use --reintegrate in the >> last >> merge: >> >> + svn update reflective-merge/trunk >> Updating 'reflective-merge/trunk': >> At revision 5. >> + svn merge file:////tmp/reflective-merge/repos/branch1 >> reflective-merge/trunk --accept postpone >> --- Merging r2 through r5 into 'reflective-merge/trunk': >> U reflective-merge/trunk/A >> C reflective-merge/trunk/folderb >> --- Recording mergeinfo for merge of r2 through r5 into >> 'reflective-merge/trunk': >> U reflective-merge/trunk >> Summary of conflicts: >> Tree conflicts: 1 >> + svn commit reflective-merge/trunk -m reintegrate branch into trunk (no >> conflicts) >> subversion/svn/commit-cmd.c:183: (apr_err=155015) >> subversion/libsvn_client/commit.c:853: (apr_err=155015) >> subversion/libsvn_client/commit.c:853: (apr_err=155015) >> svn: E155015: Commit failed (details follow): >> subversion/libsvn_client/commit_util.c:1154: (apr_err=155015) >> subversion/libsvn_client/commit_util.c:1154: (apr_err=155015) >> subversion/libsvn_client/commit_util.c:823: (apr_err=155015) >> subversion/libsvn_client/commit_util.c:329: (apr_err=155015) >> svn: E155015: Aborting commit: '/tmp/reflective-merge/trunk/folderb' >> remains in conflict >> >> To understand why you need the --reintegrate, see: >> >> http://mail-archives.apache.org/mod_mbox/subversion-dev/201107.mbox/%3c20110720124721.ga7...@ted.stsp.name%3E >> >> To understand how to repeatedly merge back and forth between the >> trunk and the branch, see here: >> >> http://svnbook.red-bean.com/en/1.7/svn.branchmerge.advanced.html#svn.branchmerge.advanced.reintegratetwice >> >> For some reason understanding the --reintegrate option seems to be >> a major usability hurdle for many when it comes to understanding merging >> in Subversion. It would be nice to just make the 'svn merge ^/foobar' >> magically do whatever people expect. But I don't see a good way of doing >> that, unfortunately. >> Once you understand what a 2-URL merge is and how that works, and that >> any merge is really just a 2-URL merge, it's really not that hard to >> understand that --reintegrate is just syntactic sugar and when you >> should use it. >> >> > A similar scenario occurs of you copied file A from trunk to branch1 >> after >> > modifying it on trunk. SVN will then throw content conflicts, telling >> you >> > that you modified the same line in the file in two branches (i.e. trunk >> > and branch1) and the text is identical. Again not sure if 1.7 fixes >> this, >> > but it is definitely present in 1.6.x >> >> Again, please verify that you're invoking the tool in the right way >> before jumping to conclusions. >> >> If you don't carefully use the right 'svn merge' invokation syntax >> for the situation at hand you can easily create conflicts for yourself. >> See also the output of 'svn help merge' in 1.7, copied here: >> http://subversion.apache.org/docs/svn-merge.txt >> > > > > -- > *Rob Pointer MSc* > Software Specialist and Consultant > rpoin...@clearvision-cm.com <mmusc...@clearvision-cm.com> > > * > Tel: +44 (0) 845 459 9530 > ** > ** > <http://www.twitter.com/clearvisioncm> > <http://www.facebook.com/clearvisioncm> > <http://www.linkedin.com/company/clearvision> > <http://www.clearvision-cm.com/rss-feed/clearvision-news> > <http://www.clearvision-cm.com/> > * > > > -- *Rob Pointer MSc* Software Specialist and Consultant rpoin...@clearvision-cm.com <mmusc...@clearvision-cm.com> * Tel: +44 (0) 845 459 9530 ** ** <http://www.twitter.com/clearvisioncm> <http://www.facebook.com/clearvisioncm> <http://www.linkedin.com/company/clearvision> <http://www.clearvision-cm.com/rss-feed/clearvision-news> <http://www.clearvision-cm.com/> *
