How to tell what paths changed in a merge?

I have a situation where somebody got confused while trying to commit/push/pull from the repository and some changes to some files got lost.

How can I tell which files got selected in a merge?

I have a log file such as shown below (produced by "git log --full-history --name-status --parents --dense")

I know that commit 693a2 had the correct files, but 1e5e6 does not. (It has an older version of the file).

So far, I've noticed one file that has gone bad in this process, and I'm worried that there may be others, so I would like to figure out exactly what got changed how at each step of the process.

But I can't figure out how to tell git-log to tell me which files it kept when merges occurred.

Any thoughts/tips/advice?

Thanks...

--wpd

commit 1e5e614e9d27902af6e1edb6ddbbca224acf3de2
693a25dc0dadfcc13786051fed9d066dac4e088c
6b1747651d06b69f96337633e785808422ed1754
Merge: 693a25d 6b17476
Author: Shawn Kelly <skkelly@mit.edu>
Date:   Fri Mar 25 14:39:01 2011 -0400

    Merge branch 'master' of skkbri2:bri2

commit 693a25dc0dadfcc13786051fed9d066dac4e088c
8da5a19daa298f87307d168c82b8b023bfe2ac58
63252fcde7ee61c06e65cd8036cec8e73d529f1c
Merge: 8da5a19 63252fc
Author: Shawn Kelly <skkelly@mit.edu>
Date:   Fri Mar 25 14:36:02 2011 -0400

    layout merge

commit 6b1747651d06b69f96337633e785808422ed1754
63252fcde7ee61c06e65cd8036cec8e73d529f1c
Author: Shawn Kelly <skkelly@mit.edu>
Date:   Wed Mar 23 19:12:27 2011 -0400

    acwtgtvss1a

A oalib/bri2/acwtgtvss1a/constraint/hierDesign.oa A oalib/bri2/acwtgtvss1a/constraint/master.tag A oalib/bri2/acwtgtvss1a/constraint/prop.cfg A oalib/bri2/acwtgtvss1a/layout/layout.oa A oalib/bri2/acwtgtvss1a/layout/master.tag A oalib/bri2/acwtgtvss1a/symbol/master.tag A oalib/bri2/acwtgtvss1a/symbol/symbol.oa

commit 63252fcde7ee61c06e65cd8036cec8e73d529f1c
dbe78c36bd1440ad537c8e55c915cb30073cbf54
18245190b4ae4c21a301d58a02d7c1d969a7700b
Merge: dbe78c3 1824519
Author: Shawn Kelly <skkelly@mit.edu>
Date:   Wed Mar 23 18:59:33 2011 -0400

    Merge branch 'master' of wfebri2:bri2

commit 8da5a19daa298f87307d168c82b8b023bfe2ac58
25316a8ef872508934a68916c27bc1e17dcdbe0e
Author: Shawn Kelly <skkelly@mit.edu>
Date:   Wed Mar 23 18:57:06 2011 -0400

On Mon, Mar 28, 2011 at 03:48:01PM -0400, Patrick Doyle wrote:

I'm not exactly sure what you mean by "selected". A merge commit is a tree state with two parent commits. So you can look at what's different in the merged state versus either parent, or there are some special ways of looking at it all together.

You might want to try:

  # show a "combined diff"; lines with +/- in the first column came from
  # the first parent of the merge (i.e., where you were when you ran
  # "git merge" or "git pull"). The ones in the second column came from
  # the second parent (the thing you merged).
  git show -c 1e5e614

  # show a condensed combined diff; this is like "-c", except that it
  # eliminates "uninteresting" hunks, where the merge took the entire
  # hunk from one parent.
  git show --cc 1e5e614

  # show the diff of the merge commit to each of its parents
  # individually
  git show -m 1e5e614

And of course you can use those options with "git log -p" to see all of the commits and what they did. You might also want to try "git log --graph" to show the structure (though it is pretty hard to read with the diffs included).

Doesn't --dense cancel out --full-history?

Sounds like somebody botched the conflict resolution. Using the show commands above should show you what happened in that case. Though from the commit messages below, I don't see any mention of conflicts, which the merge should have put in the message automatically.

So it may be that the files simply didn't change in first parent branch, but somebody reverted them to old versions (or botched a different merge) in the merged-in branch, with the end effect of reverting during the merge.

If you're still confused after looking around more, and there is nothing secret in the repo, it might work to make the repo available and tell us what you expected to see in 1e5e6, and how it differed.

-Peff

Oops... I just realized I did a "Reply" instead of "Reply-All".

It's been one of those days... sigh.

--wpd On Mon, Mar 28, 2011 at 4:47 PM, Jeff King <peff@peff.net> wrote:

and I thought this was a full-service list.  Oh well :-)

That's the bizarre thing -- "git log broken-file" doesn't show my recent modifications at all, although "git log shows my commit where I last modified the file (182451), followed (a few commits later) by his merge commit.

git show 182451:path/to/broken-file

shows my most recent change to the file.

My commit got merged with one of his at 63252 without any problems.

That tree got merged with another one of his (from a different working directory) at 693a2 and, for some reason, my original file shows up from there on forward.

I think he probably did a "git pull" which failed (most of our repository is binary CAD files, unfortunately), he probably uttered a few choice words, threw things around the room, and then grabbed his sledgehammer to force things back into the shape he wanted, and failed to notice that he left some dents in other places.

I think I'm gonna have to just go back and review each of his merge commits manually, compare the tree on one side to the tree on the other, and figure out what got changed.

It's confusing to me that I can't figure out the right options to git-log to make this easier.  "git log --name-status 693a2" doesn't list any files as having changed.  I don't know what he did to force the immediate ancestor of the file I changed to be re-committed to the repository, but somehow he did that.

My biggest concern is to wonder what else got stomped on as he wielded his sledgehammer.

I just noticed your suggestion about "gitk broken-file".  I think I'll go give that a shot and see what I can learn from that. --wpd

On Mon, Mar 28, 2011 at 9:48 PM, Jeff King <peff@peff.net> wrote:

$ git log -m --name-status

looks like it will tell me what I'm looking for... (tomorrow when I'm more awake and in better shape to try tackling this).

Thanks for your help.

--wpd