The command takes various subcommands, and different options depending
on the subcommand:
- git bisect start [--no-checkout] [<bad> [<good>...]] [--] [<paths>...]
- git bisect bad [<rev>]
- git bisect good [<rev>...]
+ git bisect start [--term-{old,good}=<term> --term-{new,bad}=<term>]
+ [--no-checkout] [<bad> [<good>...]] [--] [<paths>...]
+ git bisect (bad|new) [<rev>]
+ git bisect (good|old) [<rev>...]
+ git bisect terms [--term-good | --term-bad]
git bisect skip [(<rev>|<range>)...]
git bisect reset [<commit>]
git bisect visualize
down the range until it finds the exact commit that introduced the
change.
+In fact, `git bisect` can be used to find the commit that changed
+*any* property of your project; e.g., the commit that fixed a bug, or
+the commit that caused a benchmark's performance to improve. To
+support this more general usage, the terms "old" and "new" can be used
+in place of "good" and "bad", or you can choose your own terms. See
+section "Alternate terms" below for more information.
+
Basic bisect commands: start, bad, good
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
current bisection commit and avoid switching commits at all.
+Alternate terms
+~~~~~~~~~~~~~~~
+
+Sometimes you are not looking for the commit that introduced a
+breakage, but rather for a commit that caused a change between some
+other "old" state and "new" state. For example, you might be looking
+for the commit that introduced a particular fix. Or you might be
+looking for the first commit in which the source-code filenames were
+finally all converted to your company's naming standard. Or whatever.
+
+In such cases it can be very confusing to use the terms "good" and
+"bad" to refer to "the state before the change" and "the state after
+the change". So instead, you can use the terms "old" and "new",
+respectively, in place of "good" and "bad". (But note that you cannot
+mix "good" and "bad" with "old" and "new" in a single session.)
+
+In this more general usage, you provide `git bisect` with a "new"
+commit has some property and an "old" commit that doesn't have that
+property. Each time `git bisect` checks out a commit, you test if that
+commit has the property. If it does, mark the commit as "new";
+otherwise, mark it as "old". When the bisection is done, `git bisect`
+will report which commit introduced the property.
+
+To use "old" and "new" instead of "good" and bad, you must run `git
+bisect start` without commits as argument and then run the following
+commands to add the commits:
+
+------------------------------------------------
+git bisect old [<rev>]
+------------------------------------------------
+
+to indicate that a commit was before the sought change, or
+
+------------------------------------------------
+git bisect new [<rev>...]
+------------------------------------------------
+
+to indicate that it was after.
+
+To get a reminder of the currently used terms, use
+
+------------------------------------------------
+git bisect terms
+------------------------------------------------
+
+You can get just the old (respectively new) term with `git bisect term
+--term-old` or `git bisect term --term-good`.
+
+If you would like to use your own terms instead of "bad"/"good" or
+"new"/"old", you can choose any names you like (except existing bisect
+subcommands like `reset`, `start`, ...) by starting the
+bisection using
+
+------------------------------------------------
+git bisect start --term-old <term-old> --term-new <term-new>
+------------------------------------------------
+
+For example, if you are looking for a commit that introduced a
+performance regression, you might use
+
+------------------------------------------------
+git bisect start --term-old fast --term-new slow
+------------------------------------------------
+
+Or if you are looking for the commit that fixed a bug, you might use
+
+------------------------------------------------
+git bisect start --term-new fixed --term-old broken
+------------------------------------------------
+
+Then, use `git bisect <term-old>` and `git bisect <term-new>` instead
+of `git bisect good` and `git bisect bad` to mark commits.
+
Bisect visualize
~~~~~~~~~~~~~~~~
the revision as good or bad in the usual manner.
Bisect skip
-~~~~~~~~~~~~
+~~~~~~~~~~~
Instead of choosing a nearby commit by yourself, you can ask Git to do
it for you by issuing the command:
revision will be skipped (see `git bisect skip` above). 125 was chosen
as the highest sensible value to use for this purpose, because 126 and 127
are used by POSIX shells to signal specific error status (127 is for
-command not found, 126 is for command found but not executable---these
+command not found, 126 is for command found but not executable--these
details do not matter, as they are normal errors in the script, as far as
`bisect run` is concerned).
has at least one parent whose reachable graph is fully traversable in the sense
required by 'git pack objects'.
+* Look for a fix instead of a regression in the code
++
+------------
+$ git bisect start
+$ git bisect new HEAD # current commit is marked as new
+$ git bisect old HEAD~10 # the tenth commit from now is marked as old
+------------
++
+or:
+------------
+$ git bisect start --term-old broken --term-new fixed
+$ git bisect fixed
+$ git bisect broken HEAD~10
+------------
+
Getting help
~~~~~~~~~~~~