NAME

       hg bisect - subdivision search of changesets

SYNOPSIS

       hg bisect [-gbsr] [-U] [-c CMD] [REV]

DESCRIPTION

       This  command helps to find changesets which introduce problems. To use, mark the earliest
       changeset you know exhibits the problem as bad, then mark the latest  changeset  which  is
       free from the problem as good. Bisect will update your working directory to a revision for
       testing (unless the -U/--noupdate option is specified). Once  you  have  performed  tests,
       mark  the  working  directory  as  good  or  bad, and bisect will either update to another
       candidate changeset or announce that it has found the bad revision.

       As a shortcut, you can also use the revision argument to mark a revision as  good  or  bad
       without checking it out first.

       If  you  supply  a  command,  it  will  be  used for automatic bisection.  The environment
       variable HG_NODE will contain the ID of the changeset being tested. The exit status of the
       command  will  be used to mark revisions as good or bad: status 0 means good, 125 means to
       skip the revision, 127 (command not  found)  will  abort  the  bisection,  and  any  other
       non-zero exit status means the revision is bad.

       Some examples:

       • start a bisection with known bad revision 34, and good revision 12:

         hg bisect --bad 34
         hg bisect --good 12

       • advance the current bisection by marking current revision as good or bad:

         hg bisect --good
         hg bisect --bad

       • mark  the current revision, or a known revision, to be skipped (e.g. if that revision is
         not usable because of another issue):

         hg bisect --skip
         hg bisect --skip 23

       • skip all revisions that do not touch directories foo or bar:

         hg bisect --skip "!( file('path:foo') & file('path:bar') )"

       • forget the current bisection:

         hg bisect --reset

       • use 'make && make tests' to automatically find the first broken revision:

         hg bisect --reset
         hg bisect --bad 34
         hg bisect --good 12
         hg bisect --command "make && make tests"

       • see all changesets whose states are already known in the current bisection:

         hg log -r "bisect(pruned)"

       • see  the  changeset  currently  being  bisected  (especially  useful  if  running   with
         -U/--noupdate):

         hg log -r "bisect(current)"

       • see all changesets that took part in the current bisection:

         hg log -r "bisect(range)"

       • you can even get a nice graph:

         hg log --graph -r "bisect(range)"

         See hg help revisions.bisect for more about the bisect() predicate.

         Returns 0 on success.

OPTIONS

       -r, --reset
              reset bisect state

       -g, --good
              mark changeset good

       -b, --bad
              mark changeset bad

       -s, --skip
              skip testing changeset

       -e, --extend
              extend the bisect range

       -c,--command <CMD>
              use command to check changeset state

       -U, --noupdate
              do not update to target

                                                                                       HG(BISECT)