code.delx.au - gnu-emacs/blob - admin/notes/repo

   1 NOTES ON COMMITTING TO EMACS'S REPOSITORY    -*- outline -*-
   2
   3 ** elpa
   4
   5 This branch does not contain a copy of Emacs, but of the Emacs Lisp
   6 package archive (elpa.gnu.org).  See admin/notes/elpa for further
   7 explanation, and the README file in the branch for usage
   8 instructions.
   9
  10 * Install changes only on one branch, let them get merged elsewhere if needed.
  11
  12 In particular, install bug-fixes only on the release branch (if there
  13 is one) and let them get synced to the trunk; do not install them by
  14 hand on the trunk as well.  E.g. if there is an active "emacs-24" branch
  15 and you have a bug-fix appropriate for the next emacs-24.x release,
  16 install it only on the emacs-24 branch, not on the trunk as well.
  17
  18 Installing things manually into more than one branch makes merges more
  19 difficult.
  20
  21 http://lists.gnu.org/archive/html/emacs-devel/2010-03/msg01124.html
  22
  23 The exception is, if you know that the change will be difficult to
  24 merge to the trunk (eg because the trunk code has changed a lot).
  25 In that case, it's helpful if you can apply the change to both trunk
  26 and branch yourself (when committing the branch change, indicate
  27 in the commit log that it should not be merged to the trunk, by
  28 including the phrase "Not to be merged to master", or any other phrase
  29 that matches "merge").
  30
  31 * Installing changes from your personal branches.
  32
  33 If your branch has only a single commit, or many different real
  34 commits, it is fine to do a merge.  If your branch has only a very
  35 small number of "real" commits, but several "merge from trunks", it is
  36 preferred that you take your branch's diff, apply it to the trunk, and
  37 commit directly, not merge.  This keeps the history cleaner.
  38
  39 In general, when working on some feature in a separate branch, it is
  40 preferable not to merge from trunk until you are done with the
  41 feature.  Unless you really need some change that was done on the
  42 trunk while you were developing on the branch, you don't really need
  43 those merges; just merge once, when you are done with the feature, and
  44 Bazaar will take care of the rest.  Bazaar is much better in this than
  45 CVS, so interim merges are unnecessary.
  46
  47 Or use shelves; or rebase; or do something else.  See the thread for
  48 yet another fun excursion into the exciting world of version control.
  49
  50 http://lists.gnu.org/archive/html/emacs-devel/2010-04/msg00086.html
  51
  52 * Installing changes from gnulib
  53
  54 Some of the files in Emacs are copied from gnulib.  To synchronize
  55 these files from the version of gnulib that you have checked out into
  56 a sibling directory of your branch, type "admin/merge-gnulib"; this
  57 will check out the latest version of gnulib if there is no sibling
  58 directory already.  It is a good idea to run "git status" afterwards,
  59 so that if a gnulib module added a file, you can record the new file
  60 using "git add".  After synchronizing from gnulib, do a "make" in the
  61 usual way.
  62
  63 To change the set of gnulib modules, change the GNULIB_MODULES
  64 variable in admin/merge-gnulib before running it.
  65
  66 If you remove a gnulib module, or if a gnulib module
  67 removes a file, then remove the corresponding files by hand.
  68
  69 * How to merge changes from emacs-24 to trunk
  70
  71 [The section on git merge procedure has not yet been written]
  72
  73 Inspect the change log entries (e.g. in case too many entries have been
  74 included or whitespace between entries needs fixing). If someone made
  75 multiple change log entries on different days in the branch, you may
  76 wish to collapse them all to a single entry for that author in the
  77 trunk (because in the trunk they all appear under the same date).
  78 Obviously, if there are multiple changes to the same file by different
  79 authors, don't break the logical ordering in doing this.
  80
  81 You may see conflicts in autoload md5sums in comments.  Strictly
  82 speaking, the right thing to do is merge everything else, resolve the
  83 conflict by choosing either the trunk or branch version, then run
  84 `make -C lisp autoloads' to update the md5sums to the correct trunk
  85 value before committing.
  86
  87 * Re-adding a file that has been removed from the repository
  88
  89 Let's suppose you've done:
  90
  91 git rm file; git commit -a
  92
  93 You can just restore a copy of the file and then re-add it;
  94 git does not have per-file history so this will not harm
  95 anything.
  96
  97 Alternatively, you can do
  98
  99 git revert XXXXX
 100
 101 where XXXXX is the hash of the commit in which file was removed.
 102 This backs out the entire changeset the deletion was part of,
 103 which is often more appropriate.
 104
 105 * Undoing a commit (uncommitting)
 106
 107 If you have not pushed the commit, you may be able to use `git reset
 108 --hard' with a hash argument to revert the your local repo copy to the
 109 pre-commit state.
 110
 111 If you have pushed  commit, resetting will be ineffective because it
 112 will only vanish the commit in your local copy.  Instead, use `git
 113 revert', giving it the commit ID as argument. This will create a
 114 new commit that backs out the change. Then push that.
 115
 116 Note that git will generate a log message for the revert that includes
 117 a git hash.  Please edit this to refer to the commit by the first line
 118 of its log comment, or by committer and date, or by something else
 119 that is not the hash.  As noted previously, it is best to avoid hashes
 120 in comments in case we someday have to change version-control systems
 121 again.
 122
 123 * Bisecting
 124
 125 This is a semi-automated way to find the revision that introduced a bug.
 126 Browse `git help bisect' for technical instructions.