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Re: [PATCH 0/2] finding the fork point from reflog entries

From
John Keeping <john@keeping.me.uk>
Date
Oct 24, 2013, 21:31 UTC
Message-ID
<20131024213134.GD10779@serenity.lan>
In-Reply-To
<xmqqa9hymkma.fsf@gitster.dls.corp.google.com>
On Thu, Oct 24, 2013 at 02:20:29PM -0700, Junio C Hamano wrote:
Show 33 quoted lines
> John Keeping <john@keeping.me.uk> writes:
> 
> > On Thu, Oct 24, 2013 at 12:11:22PM -0700, Junio C Hamano wrote:
> >> The first one is a clean-up of the code to parse command line
> >> options to "git merge-base".  Options such as "--independent",
> >> "--is-ancestor" and "--octopus" are mutually exclusive and it is
> >> better expressed in terms of the recently introduced OPT_CMDMODE.
> >> 
> >> The second one implements the entire logic of the for loop we see in
> >> "git pull --rebase" directly using get_merge_bases_many() and
> >> postprocessing the result.
> >
> > Nice!  I tried this in the case where the target commit happens to be
> > the 63rd reflog entry:
> >
> > $ time sh -c 'for rev in $(git rev-list -g origin/master 2>/dev/null)
> > do
> >     git merge-base --is-ancestor $rev b2edae0 && break
> > done
> > '
> >
> > real    0m3.772s
> > user    0m3.338s
> > sys     0m0.440s
> >
> > $ time git merge-base --reflog origin/master b2edae0
> >
> > real    0m0.156s
> > user    0m0.138s
> > sys     0m0.018s
> 
> The real question is if the C code computes the same as the shell
> loop.

And in fact it doesn't - if you replace the "break" with "echo $rev" the shell version prints b2edae0... but the C version prints nothing (and exists with status 1).

Previous: Junio C HamanoNext: John Keeping
Message 30 of 35 in “rebase: use reflog to find common base with upstream”
  1. rebase: use reflog to find common base with upstreamJohn Keeping, Oct 16, 2013
  2. Jonathan NiederOct 16, 2013
  3. John KeepingOct 16, 2013
  4. Martin von ZweigbergkOct 21, 2013
  5. John KeepingOct 21, 2013
  6. Martin von ZweigbergkOct 22, 2013
  7. Junio C HamanoOct 24, 2013
  8. 0/2 finding the fork point from reflog entriesJunio C Hamano, Oct 24, 2013
  9. 1/2 merge-base: use OPT_CMDMODE and clarify the command line parsingJunio C Hamano, Oct 24, 2013
  10. 2/2 merge-base: "--reflog" mode finds fork point from reflog entriesJunio C Hamano, Oct 24, 2013
  11. Eric SunshineOct 24, 2013
  12. Junio C HamanoOct 24, 2013
  13. Eric SunshineOct 24, 2013
  14. Junio C HamanoOct 24, 2013
  15. 2/2 merge-base: "--reflog" mode finds fork point from reflog entriesJunio C Hamano, Oct 24, 2013
  16. Johannes SixtOct 25, 2013
  17. John KeepingOct 25, 2013
  18. Johannes SixtOct 25, 2013
  19. Junio C HamanoOct 25, 2013
  20. 2/2 merge-base: teach "--fork-point" modeJunio C Hamano, Oct 25, 2013
  21. Eric SunshineOct 25, 2013
  22. Martin von ZweigbergkOct 26, 2013
  23. Junio C HamanoOct 28, 2013
  24. John KeepingOct 26, 2013
  25. Junio C HamanoOct 28, 2013
  26. John KeepingOct 29, 2013
  27. Junio C HamanoOct 29, 2013
  28. John KeepingOct 24, 2013
  29. Junio C HamanoOct 24, 2013
  30. John KeepingOct 24, 2013
  31. John KeepingOct 24, 2013
  32. John KeepingOct 24, 2013
  33. Junio C HamanoOct 25, 2013
  34. Martin von ZweigbergkOct 22, 2013
  35. John KeepingOct 24, 2013

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