[Monotone-devel] monotone update problem & associated questions

[Derek Scherger]

I've just pulled in the latest monotone changes into my db and I'm trying to get them into 
my working copy but I seem to have some problems...

$ monotone update
monotone: selected update target 9cc6a827f09a1d0036ede0e117f2010846abd9b5
which: no xxdiff in 
(/home/derek/monotone/bin:/bin:/usr/bin:/usr/local/bin:/opt/bin:/usr/i686-pc-linux-gnu/gcc-bin/3.3:/opt/Acrobat5:/usr/X11R6/bin:/opt/sun-jdk-1.4.2.04/bin:/opt/sun-jdk-1.4.2.04/jre/bin:/opt/sun-jdk-1.4.2.04/jre/javaws:/usr/qt/3/bin:/usr/kde/3.2/bin:/usr/kde/3.1/bin:/usr/games/bin)
which: no emacs in 
(/home/derek/monotone/bin:/bin:/usr/bin:/usr/local/bin:/opt/bin:/usr/i686-pc-linux-gnu/gcc-bin/3.3:/opt/Acrobat5:/usr/X11R6/bin:/opt/sun-jdk-1.4.2.04/bin:/opt/sun-jdk-1.4.2.04/jre/bin:/opt/sun-jdk-1.4.2.04/jre/javaws:/usr/qt/3/bin:/usr/kde/3.2/bin:/usr/kde/3.1/bin:/usr/games/bin)
monotone: misuse: manifest merge failed, no update performed

**** error return code 1
**********  errors detected; see standard output for details  ***********

I ran this again with --verbose and it seems that I have a conflict that needs to be 
resolved, the conflicting file is configure.ac. After my previous autoconf problems I 
wasn't entirely amused! ;)

After installing xxdiff and trying the update again xxdiff pops up with 3 versions of the 
file and is set up for a 3 way merge. My problem here is that I've never really figured 
out 3 way diffs and 3 way merges so that makes this a bit difficult. In the end I simply 
quit out of xxdiff expecting that I'd remain in the same, conflicted state.

Re-running the update after looking at things with xxdiff it seems as though my tree is up 
to date, although my configure.ac has a bunch of changes that I didn't make and didn't 
expect to see.

So now I have several (probably too many) questions and thoughs.

1.  Should I have done monotone merge before trying to do monotone update or would that 
have done nothing for me in this case?

2. It seems a bit odd to me (coming from cvs I guess) that monotone merge will make 
changes and commit them to my local db rather than just in my working copy. Probably I 
just don't understand what it's supposed do or how it works.

3. It would probably be good to report what the problem was above (file configure.ac has 
conflicts and I have no conflict resolution tool installed) rather than failing with a 
not-so-helpful error.

4. Would it be possible to have cvs style conflict markers rather than using xxdiff or 
emacs to resolve conflicts? Until I really get the 3 way diff/merge stuff I'm not even 
sure this makes sense.

5. Now that my conflict has been resolved by xxdiff, even though I actually intended not 
to resolve it, it would be good to be able to revert a single file rather than my entire 
working copy. It appears that revert currently does not allow this and will revert my 
entire tree, but it seems like it should be easy to do (conceptually at least). Another 
thought, can I simply remove the file and do another update (cvs style revert)?

6. The options for 3 way merge tools are xxdiff and emacs. I happen to use xemacs, which 
probably (?) has similar support as emacs does (ediff I expect). Should this also be 
considered as an option?

7. While xxdiff was running my database was apparently locked and attempts to execute 
other monotone commands failed somewhat miserably. It would be good (from my perspective 
at least) to report some useful error message. It's probably fine not to handle multiple 
processes working with the db at the same time though. (I seem to remember seeing a 
comment to this effect with a "... you get what you pay for" tacked on the end of it ;) )

8. When updating my working copy, is the entire update an atomic operation, or does each 
file update represent it's own little filesystem transaction?

I Hope I'm not overwhelming you with feedback! I'm actually liking montone a 
lot.
--
Cheers,
Derek