git-bisect.sh - git - Git at Google

 #!/bin/sh

 USAGE='[start|bad|good|skip|next|reset|visualize|replay|log|run]'
 LONG_USAGE='git bisect start [<bad> [<good>...]] [--] [<pathspec>...]
         reset bisect state and start bisection.
 git bisect bad [<rev>]
         mark <rev> a known-bad revision.
 git bisect good [<rev>...]
         mark <rev>... known-good revisions.
 git bisect skip [<rev>...]
         mark <rev>... untestable revisions.
 git bisect next
         find next bisection to test and check it out.
 git bisect reset [<branch>]
         finish bisection search and go back to branch.
 git bisect visualize
         show bisect status in gitk.
 git bisect replay <logfile>
         replay bisection log.
 git bisect log
         show bisect log.
 git bisect run <cmd>...
         use <cmd>... to automatically bisect.'

 OPTIONS_SPEC=
 . git-sh-setup
 require_work_tree

 sq() {
 	@@PERL@@ -e '
 		for (@ARGV) {
 			s/'\''/'\'\\\\\'\''/g;
 			print " '\''$_'\''";
 		}
 		print "\n";
 	' "$@"
 }

 bisect_autostart() {
 	test -f "$GIT_DIR/BISECT_NAMES" || {
 		echo >&2 'You need to start by "git bisect start"'
 		if test -t 0
 		then
 			echo >&2 -n 'Do you want me to do it for you [Y/n]? '
 			read yesno
 			case "$yesno" in
 			[Nn]*)
 				exit ;;
 			esac
 			bisect_start
 		else
 			exit 1
 		fi
 	}
 }

 bisect_start() {
 	#
 	# Verify HEAD. If we were bisecting before this, reset to the
 	# top-of-line master first!
 	#
 	head=$(GIT_DIR="$GIT_DIR" git symbolic-ref HEAD) ||
 	die "Bad HEAD - I need a symbolic ref"
 	case "$head" in
 	refs/heads/bisect)
 		if [ -s "$GIT_DIR/head-name" ]; then
 		    branch=`cat "$GIT_DIR/head-name"`
 		else
 		    branch=master
 		fi
 		git checkout $branch || exit
 		;;
 	refs/heads/*)
 		[ -s "$GIT_DIR/head-name" ] && die "won't bisect on seeked tree"
 		echo "${head#refs/heads/}" >"$GIT_DIR/head-name"
 		;;
 	*)
 		die "Bad HEAD - strange symbolic ref"
 		;;
 	esac

 	#
 	# Get rid of any old bisect state
 	#
 	bisect_clean_state

 	#
 	# Check for one bad and then some good revisions.
 	#
 	has_double_dash=0
 	for arg; do
 	    case "$arg" in --) has_double_dash=1; break ;; esac
 	done
 	orig_args=$(sq "$@")
 	bad_seen=0
 	while [ $# -gt 0 ]; do
 	    arg="$1"
 	    case "$arg" in
 	    --)
 		shift
 		break
 		;;
 	    *)
 		rev=$(git rev-parse --verify "$arg^{commit}" 2>/dev/null) || {
 		    test $has_double_dash -eq 1 &&
 		        die "'$arg' does not appear to be a valid revision"
 		    break
 		}
 		case $bad_seen in
 		0) state='bad' ; bad_seen=1 ;;
 		*) state='good' ;;
 		esac
 		bisect_write "$state" "$rev" 'nolog'
 		shift
 		;;
 	    esac
 	done

 	sq "$@" >"$GIT_DIR/BISECT_NAMES"
 	echo "git-bisect start$orig_args" >>"$GIT_DIR/BISECT_LOG"
 	bisect_auto_next
 }

 bisect_write() {
 	state="$1"
 	rev="$2"
 	nolog="$3"
 	case "$state" in
 		bad)		tag="$state" ;;
 		good|skip)	tag="$state"-"$rev" ;;
 		*)		die "Bad bisect_write argument: $state" ;;
 	esac
 	git update-ref "refs/bisect/$tag" "$rev"
 	echo "# $state: "$(git show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
 	test -z "$nolog" && echo "git-bisect $state $rev" >>"$GIT_DIR/BISECT_LOG"
 }

 bisect_state() {
 	bisect_autostart
 	state=$1
 	case "$#,$state" in
 	0,*)
 		die "Please call 'bisect_state' with at least one argument." ;;
 	1,bad|1,good|1,skip)
 		rev=$(git rev-parse --verify HEAD) ||
 			die "Bad rev input: HEAD"
 		bisect_write "$state" "$rev" ;;
 	2,bad)
 		rev=$(git rev-parse --verify "$2^{commit}") ||
 			die "Bad rev input: $2"
 		bisect_write "$state" "$rev" ;;
 	*,good|*,skip)
 		shift
 		revs=$(git rev-parse --revs-only --no-flags "$@") &&
 			test '' != "$revs" || die "Bad rev input: $@"
 		for rev in $revs
 		do
 			rev=$(git rev-parse --verify "$rev^{commit}") ||
 				die "Bad rev commit: $rev^{commit}"
 			bisect_write "$state" "$rev"
 		done ;;
 	*)
 		usage ;;
 	esac
 	bisect_auto_next
 }

 bisect_next_check() {
 	missing_good= missing_bad=
 	git show-ref -q --verify refs/bisect/bad || missing_bad=t
 	test -n "$(git for-each-ref "refs/bisect/good-*")" || missing_good=t

 	case "$missing_good,$missing_bad,$1" in
 	,,*)
 		: have both good and bad - ok
 		;;
 	*,)
 		# do not have both but not asked to fail - just report.
 		false
 		;;
 	t,,good)
 		# have bad but not good.  we could bisect although
 		# this is less optimum.
 		echo >&2 'Warning: bisecting only with a bad commit.'
 		if test -t 0
 		then
 			printf >&2 'Are you sure [Y/n]? '
 			case "$(read yesno)" in [Nn]*) exit 1 ;; esac
 		fi
 		: bisect without good...
 		;;
 	*)
 		THEN=''
 		test -f "$GIT_DIR/BISECT_NAMES" || {
 			echo >&2 'You need to start by "git bisect start".'
 			THEN='then '
 		}
 		echo >&2 'You '$THEN'need to give me at least one good' \
 			'and one bad revisions.'
 		echo >&2 '(You can use "git bisect bad" and' \
 			'"git bisect good" for that.)'
 		exit 1 ;;
 	esac
 }

 bisect_auto_next() {
 	bisect_next_check && bisect_next || :
 }

 filter_skipped() {
 	_eval="$1"
 	_skip="$2"

 	if [ -z "$_skip" ]; then
 		eval $_eval
 		return
 	fi

 	# Let's parse the output of:
 	# "git rev-list --bisect-vars --bisect-all ..."
 	eval $_eval | while read hash line
 	do
 		case "$VARS,$FOUND,$TRIED,$hash" in
 			# We display some vars.
 			1,*,*,*) echo "$hash $line" ;;

 			# Split line.
 			,*,*,---*) ;;

 			# We had nothing to search.
 			,,,bisect_rev*)
 				echo "bisect_rev="
 				VARS=1
 				;;

 			# We did not find a good bisect rev.
 			# This should happen only if the "bad"
 			# commit is also a "skip" commit.
 			,,*,bisect_rev*)
 				echo "bisect_rev=$TRIED"
 				VARS=1
 				;;

 			# We are searching.
 			,,*,*)
 				TRIED="${TRIED:+$TRIED|}$hash"
 				case "$_skip" in
 				*$hash*) ;;
 				*)
 					echo "bisect_rev=$hash"
 					echo "bisect_tried=\"$TRIED\""
 					FOUND=1
 					;;
 				esac
 				;;

 			# We have already found a rev to be tested.
 			,1,*,bisect_rev*) VARS=1 ;;
 			,1,*,*) ;;

 			# ???
 			*) die "filter_skipped error " \
 			    "VARS: '$VARS' " \
 			    "FOUND: '$FOUND' " \
 			    "TRIED: '$TRIED' " \
 			    "hash: '$hash' " \
 			    "line: '$line'"
 			;;
 		esac
 	done
 }

 exit_if_skipped_commits () {
 	_tried=$1
 	if expr "$_tried" : ".*[|].*" > /dev/null ; then
 		echo "There are only 'skip'ped commit left to test."
 		echo "The first bad commit could be any of:"
 		echo "$_tried" | tr '[|]' '[\012]'
 		echo "We cannot bisect more!"
 		exit 2
 	fi
 }

 bisect_next() {
 	case "$#" in 0) ;; *) usage ;; esac
 	bisect_autostart
 	bisect_next_check good

 	skip=$(git for-each-ref --format='%(objectname)' \
 		"refs/bisect/skip-*" | tr '[\012]' ' ') || exit

 	BISECT_OPT=''
 	test -n "$skip" && BISECT_OPT='--bisect-all'

 	bad=$(git rev-parse --verify refs/bisect/bad) &&
 	good=$(git for-each-ref --format='^%(objectname)' \
 		"refs/bisect/good-*" | tr '[\012]' ' ') &&
 	eval="git rev-list --bisect-vars $BISECT_OPT $good $bad --" &&
 	eval="$eval $(cat "$GIT_DIR/BISECT_NAMES")" &&
 	eval=$(filter_skipped "$eval" "$skip") &&
 	eval "$eval" || exit

 	if [ -z "$bisect_rev" ]; then
 		echo "$bad was both good and bad"
 		exit 1
 	fi
 	if [ "$bisect_rev" = "$bad" ]; then
 		exit_if_skipped_commits "$bisect_tried"
 		echo "$bisect_rev is first bad commit"
 		git diff-tree --pretty $bisect_rev
 		exit 0
 	fi

 	# We should exit here only if the "bad"
 	# commit is also a "skip" commit (see above).
 	exit_if_skipped_commits "$bisect_rev"

 	echo "Bisecting: $bisect_nr revisions left to test after this"
 	git branch -f new-bisect "$bisect_rev"
 	git checkout -q new-bisect || exit
 	git branch -M new-bisect bisect
 	git show-branch "$bisect_rev"
 }

 bisect_visualize() {
 	bisect_next_check fail

 	if test $# = 0
 	then
 		case "${DISPLAY+set}" in
 		'')	set git log ;;
 		set)	set gitk ;;
 		esac
 	else
 		case "$1" in
 		git*|tig) ;;
 		-*)	set git log "$@" ;;
 		*)	set git "$@" ;;
 		esac
 	fi

 	not=$(git for-each-ref --format='%(refname)' "refs/bisect/good-*")
 	eval '"$@"' refs/bisect/bad --not $not -- $(cat "$GIT_DIR/BISECT_NAMES")
 }

 bisect_reset() {
 	test -f "$GIT_DIR/BISECT_NAMES" || {
 		echo "We are not bisecting."
 		return
 	}
 	case "$#" in
 	0) if [ -s "$GIT_DIR/head-name" ]; then
 	       branch=`cat "$GIT_DIR/head-name"`
 	   else
 	       branch=master
 	   fi ;;
 	1) git show-ref --verify --quiet -- "refs/heads/$1" ||
 	       die "$1 does not seem to be a valid branch"
 	   branch="$1" ;;
 	*)
 	    usage ;;
 	esac
 	if git checkout "$branch"; then
 		rm -f "$GIT_DIR/head-name"
 		bisect_clean_state
 	fi
 }

 bisect_clean_state() {
 	# There may be some refs packed during bisection.
 	git for-each-ref --format='%(refname) %(objectname)' refs/bisect/\* refs/heads/bisect |
 	while read ref hash
 	do
 		git update-ref -d $ref $hash
 	done
 	rm -f "$GIT_DIR/BISECT_LOG"
 	rm -f "$GIT_DIR/BISECT_NAMES"
 	rm -f "$GIT_DIR/BISECT_RUN"
 }

 bisect_replay () {
 	test -r "$1" || die "cannot read $1 for replaying"
 	bisect_reset
 	while read bisect command rev
 	do
 		test "$bisect" = "git-bisect" || continue
 		case "$command" in
 		start)
 			cmd="bisect_start $rev"
 			eval "$cmd" ;;
 		good|bad|skip)
 			bisect_write "$command" "$rev" ;;
 		*)
 			die "?? what are you talking about?" ;;
 		esac
 	done <"$1"
 	bisect_auto_next
 }

 bisect_run () {
     bisect_next_check fail

     while true
     do
       echo "running $@"
       "$@"
       res=$?

       # Check for really bad run error.
       if [ $res -lt 0 -o $res -ge 128 ]; then
 	  echo >&2 "bisect run failed:"
 	  echo >&2 "exit code $res from '$@' is < 0 or >= 128"
 	  exit $res
       fi

       # Find current state depending on run success or failure.
       # A special exit code of 125 means cannot test.
       if [ $res -eq 125 ]; then
 	  state='skip'
       elif [ $res -gt 0 ]; then
 	  state='bad'
       else
 	  state='good'
       fi

       # We have to use a subshell because "bisect_state" can exit.
       ( bisect_state $state > "$GIT_DIR/BISECT_RUN" )
       res=$?

       cat "$GIT_DIR/BISECT_RUN"

       if grep "first bad commit could be any of" "$GIT_DIR/BISECT_RUN" \
 		> /dev/null; then
 	  echo >&2 "bisect run cannot continue any more"
 	  exit $res
       fi

       if [ $res -ne 0 ]; then
 	  echo >&2 "bisect run failed:"
 	  echo >&2 "'bisect_state $state' exited with error code $res"
 	  exit $res
       fi

       if grep "is first bad commit" "$GIT_DIR/BISECT_RUN" > /dev/null; then
 	  echo "bisect run success"
 	  exit 0;
       fi

     done
 }


 case "$#" in
 0)
     usage ;;
 *)
     cmd="$1"
     shift
     case "$cmd" in
     start)
         bisect_start "$@" ;;
     bad|good|skip)
         bisect_state "$cmd" "$@" ;;
     next)
         # Not sure we want "next" at the UI level anymore.
         bisect_next "$@" ;;
     visualize|view)
 	bisect_visualize "$@" ;;
     reset)
         bisect_reset "$@" ;;
     replay)
 	bisect_replay "$@" ;;
     log)
 	cat "$GIT_DIR/BISECT_LOG" ;;
     run)
         bisect_run "$@" ;;
     *)
         usage ;;
     esac
 esac
	#!/bin/sh

	USAGE='[start\|bad\|good\|skip\|next\|reset\|visualize\|replay\|log\|run]'
	LONG_USAGE='git bisect start [<bad> [<good>...]] [--] [<pathspec>...]
	reset bisect state and start bisection.
	git bisect bad [<rev>]
	mark <rev> a known-bad revision.
	git bisect good [<rev>...]
	mark <rev>... known-good revisions.
	git bisect skip [<rev>...]
	mark <rev>... untestable revisions.
	git bisect next
	find next bisection to test and check it out.
	git bisect reset [<branch>]
	finish bisection search and go back to branch.
	git bisect visualize
	show bisect status in gitk.
	git bisect replay <logfile>
	replay bisection log.
	git bisect log
	show bisect log.
	git bisect run <cmd>...
	use <cmd>... to automatically bisect.'

	OPTIONS_SPEC=
	. git-sh-setup
	require_work_tree

	sq() {
	@@PERL@@ -e '
	for (@ARGV) {
	s/'\''/'\'\\\\\'\''/g;
	print " '\''$_'\''";
	}
	print "\n";
	' "$@"
	}

	bisect_autostart() {
	test -f "$GIT_DIR/BISECT_NAMES" \|\| {
	echo >&2 'You need to start by "git bisect start"'
	if test -t 0
	then
	echo >&2 -n 'Do you want me to do it for you [Y/n]? '
	read yesno
	case "$yesno" in
	[Nn]*)
	exit ;;
	esac
	bisect_start
	else
	exit 1
	fi
	}
	}

	bisect_start() {
	#
	# Verify HEAD. If we were bisecting before this, reset to the
	# top-of-line master first!
	#
	head=$(GIT_DIR="$GIT_DIR" git symbolic-ref HEAD) \|\|
	die "Bad HEAD - I need a symbolic ref"
	case "$head" in
	refs/heads/bisect)
	if [ -s "$GIT_DIR/head-name" ]; then
	branch=`cat "$GIT_DIR/head-name"`
	else
	branch=master
	fi
	git checkout $branch \|\| exit
	;;
	refs/heads/*)
	[ -s "$GIT_DIR/head-name" ] && die "won't bisect on seeked tree"
	echo "${head#refs/heads/}" >"$GIT_DIR/head-name"
	;;
	*)
	die "Bad HEAD - strange symbolic ref"
	;;
	esac

	#
	# Get rid of any old bisect state
	#
	bisect_clean_state

	#
	# Check for one bad and then some good revisions.
	#
	has_double_dash=0
	for arg; do
	case "$arg" in --) has_double_dash=1; break ;; esac
	done
	orig_args=$(sq "$@")
	bad_seen=0
	while [ $# -gt 0 ]; do
	arg="$1"
	case "$arg" in
	--)
	shift
	break
	;;
	*)
	rev=$(git rev-parse --verify "$arg^{commit}" 2>/dev/null) \|\| {
	test $has_double_dash -eq 1 &&
	die "'$arg' does not appear to be a valid revision"
	break
	}
	case $bad_seen in
	0) state='bad' ; bad_seen=1 ;;
	*) state='good' ;;
	esac
	bisect_write "$state" "$rev" 'nolog'
	shift
	;;
	esac
	done

	sq "$@" >"$GIT_DIR/BISECT_NAMES"
	echo "git-bisect start$orig_args" >>"$GIT_DIR/BISECT_LOG"
	bisect_auto_next
	}

	bisect_write() {
	state="$1"
	rev="$2"
	nolog="$3"
	case "$state" in
	bad) tag="$state" ;;
	good\|skip) tag="$state"-"$rev" ;;
	*) die "Bad bisect_write argument: $state" ;;
	esac
	git update-ref "refs/bisect/$tag" "$rev"
	echo "# $state: "$(git show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
	test -z "$nolog" && echo "git-bisect $state $rev" >>"$GIT_DIR/BISECT_LOG"
	}

	bisect_state() {
	bisect_autostart
	state=$1
	case "$#,$state" in
	0,*)
	die "Please call 'bisect_state' with at least one argument." ;;
	1,bad\|1,good\|1,skip)
	rev=$(git rev-parse --verify HEAD) \|\|
	die "Bad rev input: HEAD"
	bisect_write "$state" "$rev" ;;
	2,bad)
	rev=$(git rev-parse --verify "$2^{commit}") \|\|
	die "Bad rev input: $2"
	bisect_write "$state" "$rev" ;;
	,good\|,skip)
	shift
	revs=$(git rev-parse --revs-only --no-flags "$@") &&
	test '' != "$revs" \|\| die "Bad rev input: $@"
	for rev in $revs
	do
	rev=$(git rev-parse --verify "$rev^{commit}") \|\|
	die "Bad rev commit: $rev^{commit}"
	bisect_write "$state" "$rev"
	done ;;
	*)
	usage ;;
	esac
	bisect_auto_next
	}

	bisect_next_check() {
	missing_good= missing_bad=
	git show-ref -q --verify refs/bisect/bad \|\| missing_bad=t
	test -n "$(git for-each-ref "refs/bisect/good-*")" \|\| missing_good=t

	case "$missing_good,$missing_bad,$1" in
	,,*)
	: have both good and bad - ok
	;;
	*,)
	# do not have both but not asked to fail - just report.
	false
	;;
	t,,good)
	# have bad but not good. we could bisect although
	# this is less optimum.
	echo >&2 'Warning: bisecting only with a bad commit.'
	if test -t 0
	then
	printf >&2 'Are you sure [Y/n]? '
	case "$(read yesno)" in [Nn]*) exit 1 ;; esac
	fi
	: bisect without good...
	;;
	*)
	THEN=''
	test -f "$GIT_DIR/BISECT_NAMES" \|\| {
	echo >&2 'You need to start by "git bisect start".'
	THEN='then '
	}
	echo >&2 'You '$THEN'need to give me at least one good' \
	'and one bad revisions.'
	echo >&2 '(You can use "git bisect bad" and' \
	'"git bisect good" for that.)'
	exit 1 ;;
	esac
	}

	bisect_auto_next() {
	bisect_next_check && bisect_next \|\| :
	}

	filter_skipped() {
	_eval="$1"
	_skip="$2"

	if [ -z "$_skip" ]; then
	eval $_eval
	return
	fi

	# Let's parse the output of:
	# "git rev-list --bisect-vars --bisect-all ..."
	eval $_eval \| while read hash line
	do
	case "$VARS,$FOUND,$TRIED,$hash" in
	# We display some vars.
	1,,,*) echo "$hash $line" ;;

	# Split line.
	,,,---*) ;;

	# We had nothing to search.
	,,,bisect_rev*)
	echo "bisect_rev="
	VARS=1
	;;

	# We did not find a good bisect rev.
	# This should happen only if the "bad"
	# commit is also a "skip" commit.
	,,,bisect_rev)
	echo "bisect_rev=$TRIED"
	VARS=1
	;;

	# We are searching.
	,,,)
	TRIED="${TRIED:+$TRIED\|}$hash"
	case "$_skip" in
	$hash) ;;
	*)
	echo "bisect_rev=$hash"
	echo "bisect_tried=\"$TRIED\""
	FOUND=1
	;;
	esac
	;;

	# We have already found a rev to be tested.
	,1,,bisect_rev) VARS=1 ;;
	,1,,) ;;

	# ???
	*) die "filter_skipped error " \
	"VARS: '$VARS' " \
	"FOUND: '$FOUND' " \
	"TRIED: '$TRIED' " \
	"hash: '$hash' " \
	"line: '$line'"
	;;
	esac
	done
	}

	exit_if_skipped_commits () {
	_tried=$1
	if expr "$_tried" : ".[\|]." > /dev/null ; then
	echo "There are only 'skip'ped commit left to test."
	echo "The first bad commit could be any of:"
	echo "$_tried" \| tr '[\|]' '[\012]'
	echo "We cannot bisect more!"
	exit 2
	fi
	}

	bisect_next() {
	case "$#" in 0) ;; *) usage ;; esac
	bisect_autostart
	bisect_next_check good

	skip=$(git for-each-ref --format='%(objectname)' \
	"refs/bisect/skip-*" \| tr '[\012]' ' ') \|\| exit

	BISECT_OPT=''
	test -n "$skip" && BISECT_OPT='--bisect-all'

	bad=$(git rev-parse --verify refs/bisect/bad) &&
	good=$(git for-each-ref --format='^%(objectname)' \
	"refs/bisect/good-*" \| tr '[\012]' ' ') &&
	eval="git rev-list --bisect-vars $BISECT_OPT $good $bad --" &&
	eval="$eval $(cat "$GIT_DIR/BISECT_NAMES")" &&
	eval=$(filter_skipped "$eval" "$skip") &&
	eval "$eval" \|\| exit

	if [ -z "$bisect_rev" ]; then
	echo "$bad was both good and bad"
	exit 1
	fi
	if [ "$bisect_rev" = "$bad" ]; then
	exit_if_skipped_commits "$bisect_tried"
	echo "$bisect_rev is first bad commit"
	git diff-tree --pretty $bisect_rev
	exit 0
	fi

	# We should exit here only if the "bad"
	# commit is also a "skip" commit (see above).
	exit_if_skipped_commits "$bisect_rev"

	echo "Bisecting: $bisect_nr revisions left to test after this"
	git branch -f new-bisect "$bisect_rev"
	git checkout -q new-bisect \|\| exit
	git branch -M new-bisect bisect
	git show-branch "$bisect_rev"
	}

	bisect_visualize() {
	bisect_next_check fail

	if test $# = 0
	then
	case "${DISPLAY+set}" in
	'') set git log ;;
	set) set gitk ;;
	esac
	else
	case "$1" in
	git*\|tig) ;;
	-*) set git log "$@" ;;
	*) set git "$@" ;;
	esac
	fi

	not=$(git for-each-ref --format='%(refname)' "refs/bisect/good-*")
	eval '"$@"' refs/bisect/bad --not $not -- $(cat "$GIT_DIR/BISECT_NAMES")
	}

	bisect_reset() {
	test -f "$GIT_DIR/BISECT_NAMES" \|\| {
	echo "We are not bisecting."
	return
	}
	case "$#" in
	0) if [ -s "$GIT_DIR/head-name" ]; then
	branch=`cat "$GIT_DIR/head-name"`
	else
	branch=master
	fi ;;
	1) git show-ref --verify --quiet -- "refs/heads/$1" \|\|
	die "$1 does not seem to be a valid branch"
	branch="$1" ;;
	*)
	usage ;;
	esac
	if git checkout "$branch"; then
	rm -f "$GIT_DIR/head-name"
	bisect_clean_state
	fi
	}

	bisect_clean_state() {
	# There may be some refs packed during bisection.
	git for-each-ref --format='%(refname) %(objectname)' refs/bisect/\* refs/heads/bisect \|
	while read ref hash
	do
	git update-ref -d $ref $hash
	done
	rm -f "$GIT_DIR/BISECT_LOG"
	rm -f "$GIT_DIR/BISECT_NAMES"
	rm -f "$GIT_DIR/BISECT_RUN"
	}

	bisect_replay () {
	test -r "$1" \|\| die "cannot read $1 for replaying"
	bisect_reset
	while read bisect command rev
	do
	test "$bisect" = "git-bisect" \|\| continue
	case "$command" in
	start)
	cmd="bisect_start $rev"
	eval "$cmd" ;;
	good\|bad\|skip)
	bisect_write "$command" "$rev" ;;
	*)
	die "?? what are you talking about?" ;;
	esac
	done <"$1"
	bisect_auto_next
	}

	bisect_run () {
	bisect_next_check fail

	while true
	do
	echo "running $@"
	"$@"
	res=$?

	# Check for really bad run error.
	if [ $res -lt 0 -o $res -ge 128 ]; then
	echo >&2 "bisect run failed:"
	echo >&2 "exit code $res from '$@' is < 0 or >= 128"
	exit $res
	fi

	# Find current state depending on run success or failure.
	# A special exit code of 125 means cannot test.
	if [ $res -eq 125 ]; then
	state='skip'
	elif [ $res -gt 0 ]; then
	state='bad'
	else
	state='good'
	fi

	# We have to use a subshell because "bisect_state" can exit.
	( bisect_state $state > "$GIT_DIR/BISECT_RUN" )
	res=$?

	cat "$GIT_DIR/BISECT_RUN"

	if grep "first bad commit could be any of" "$GIT_DIR/BISECT_RUN" \
	> /dev/null; then
	echo >&2 "bisect run cannot continue any more"
	exit $res
	fi

	if [ $res -ne 0 ]; then
	echo >&2 "bisect run failed:"
	echo >&2 "'bisect_state $state' exited with error code $res"
	exit $res
	fi

	if grep "is first bad commit" "$GIT_DIR/BISECT_RUN" > /dev/null; then
	echo "bisect run success"
	exit 0;
	fi

	done
	}


	case "$#" in
	0)
	usage ;;
	*)
	cmd="$1"
	shift
	case "$cmd" in
	start)
	bisect_start "$@" ;;
	bad\|good\|skip)
	bisect_state "$cmd" "$@" ;;
	next)
	# Not sure we want "next" at the UI level anymore.
	bisect_next "$@" ;;
	visualize\|view)
	bisect_visualize "$@" ;;
	reset)
	bisect_reset "$@" ;;
	replay)
	bisect_replay "$@" ;;
	log)
	cat "$GIT_DIR/BISECT_LOG" ;;
	run)
	bisect_run "$@" ;;
	*)
	usage ;;
	esac
	esac