Help: bisect

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

subdivision search of changesets

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.


-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

global options ([+] can be repeated):

-R --repository REPO repository root directory or name of overlay bundle file
--cwd DIR change working directory
-y --noninteractive do not prompt, automatically pick the first choice for all prompts
-q --quiet suppress output
-v --verbose enable additional output
--color TYPE when to colorize (boolean, always, auto, never, or debug)
--config CONFIG [+] set/override config option (use '')
--debug enable debugging output
--debugger start debugger
--encoding ENCODE set the charset encoding (default: UTF-8)
--encodingmode MODE set the charset encoding mode (default: strict)
--traceback always print a traceback on exception
--time time how long the command takes
--profile print command execution profile
--version output version information and exit
-h --help display help and exit
--hidden consider hidden changesets
--pager TYPE when to paginate (boolean, always, auto, or never) (default: auto)