* admin/notes/bzr (Commit emails): New section.

[bpt/emacs.git] / admin / notes / bzr

diff --git a/admin/notes/bzr b/admin/notes/bzr
index cdcfa7e..1b714a6 100644 (file)
--- a/admin/notes/bzr
+++ b/admin/notes/bzr
@@ -267,3 +267,82 @@ For example, on RHEL6 I needed:
   yum --enablerepo=epel install python-simpletal
 
 Then point your web-browser to http://127.0.0.1:8080/ .
+
+* Bisecting
+
+This is a semi-automated way to find the revision that introduced a bug.
+
+First, get the bzr bisect plugin if you do not have it already:
+
+  cd ~/.bazaar/plugins
+  bzr branch lp:bzr-bisect bisect
+
+`bzr help bisect' should work now.
+
+It's probably simplest to make a new copy of the branch to work in
+from this point onwards.
+
+Identify the last known "good" revision where the relevant issue is
+NOT present (e.g. maybe Emacs 24.1).  Let's say this is revision 1000.
+
+  bzr bisect start
+  bzr bisect no -r 1000
+
+At this point, bzr will switch to the mid-point of revision 1000 and
+the current revision.  If you know that the issue was definitely
+present in some specific revision (say 2000), you can use:
+
+  bzr bisect yes -r 2000
+
+Now bzr switches to revision 1500.
+
+Now test whether the issue is present.  You might need to rebuild
+Emacs to do this, or if you know the problem is in a specific Lisp
+file, you might be able to get away with just loading that one file in
+current Emacs.
+
+If the issue is present, use
+
+  bzr bisect yes
+
+If it is not, use
+
+  bzr bisect no
+
+Repeat until you zero-in on the specific revision.
+
+When finished, use
+
+  bzr bisect reset
+
+or simply delete the entire branch if you created it just for this.
+
+* Commit emails
+
+** Old method: bzr-hookless-email
+https://launchpad.net/bzr-hookless-email
+
+Runs hourly via cron.  Must ask Savannah admins to enable/disable it
+for each branch.  Stores the last revision that it mailed as
+last_revision_mailed in branch.conf on the server.  Breaks with bzr 2.6:
+
+http://lists.gnu.org/archive/html/savannah-hackers-public/2013-05/msg00000.html
+
+Fix from https://bugs.launchpad.net/bzr-hookless-email/+bug/988195
+only partially works.  Breaks again on every merge commit:
+
+https://lists.ubuntu.com/archives/bazaar/2013q2/075520.html
+http://lists.gnu.org/archive/html/savannah-hackers-public/2013-05/msg00024.html
+
+You can force it to skip the merge commit by changing the value for
+last_revision_mailed, eg:
+
+bzr config last_revision_mailed=xfq.free@gmail.com-20130603233720-u1aumaxvf3o0rlai -d bzr+ssh://USERNAME@bzr.savannah.gnu.org/emacs/trunk/
+
+** New method: bzr-email plugin
+https://launchpad.net/bzr-email
+http://lists.gnu.org/archive/html/savannah-hackers-public/2013-06/msg00007.html
+
+Runs on commit.  Projects can enable it themselves by using `bzr
+config' to set post_commit_to option for a branch.  See `bzr help email'
+(if you have the plugin installed) for other options.