reflog --expire-unreachable: avoid merge-base computation
[git] / git-bisect.sh
1 #!/bin/sh
2
3 USAGE='[help|start|bad|good|skip|next|reset|visualize|replay|log|run]'
4 LONG_USAGE='git bisect help
5         print this long help message.
6 git bisect start [<bad> [<good>...]] [--] [<pathspec>...]
7         reset bisect state and start bisection.
8 git bisect bad [<rev>]
9         mark <rev> a known-bad revision.
10 git bisect good [<rev>...]
11         mark <rev>... known-good revisions.
12 git bisect skip [(<rev>|<range>)...]
13         mark <rev>... untestable revisions.
14 git bisect next
15         find next bisection to test and check it out.
16 git bisect reset [<commit>]
17         finish bisection search and go back to commit.
18 git bisect visualize
19         show bisect status in gitk.
20 git bisect replay <logfile>
21         replay bisection log.
22 git bisect log
23         show bisect log.
24 git bisect run <cmd>...
25         use <cmd>... to automatically bisect.
26
27 Please use "git help bisect" to get the full man page.'
28
29 OPTIONS_SPEC=
30 . git-sh-setup
31 require_work_tree
32
33 _x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
34 _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
35
36 bisect_autostart() {
37         test -s "$GIT_DIR/BISECT_START" || {
38                 echo >&2 'You need to start by "git bisect start"'
39                 if test -t 0
40                 then
41                         echo >&2 -n 'Do you want me to do it for you [Y/n]? '
42                         read yesno
43                         case "$yesno" in
44                         [Nn]*)
45                                 exit ;;
46                         esac
47                         bisect_start
48                 else
49                         exit 1
50                 fi
51         }
52 }
53
54 bisect_start() {
55         #
56         # Verify HEAD.
57         #
58         head=$(GIT_DIR="$GIT_DIR" git symbolic-ref -q HEAD) ||
59         head=$(GIT_DIR="$GIT_DIR" git rev-parse --verify HEAD) ||
60         die "Bad HEAD - I need a HEAD"
61
62         #
63         # Check if we are bisecting.
64         #
65         start_head=''
66         if test -s "$GIT_DIR/BISECT_START"
67         then
68                 # Reset to the rev from where we started.
69                 start_head=$(cat "$GIT_DIR/BISECT_START")
70                 git checkout "$start_head" -- || exit
71         else
72                 # Get rev from where we start.
73                 case "$head" in
74                 refs/heads/*|$_x40)
75                         # This error message should only be triggered by
76                         # cogito usage, and cogito users should understand
77                         # it relates to cg-seek.
78                         [ -s "$GIT_DIR/head-name" ] &&
79                                 die "won't bisect on seeked tree"
80                         start_head="${head#refs/heads/}"
81                         ;;
82                 *)
83                         die "Bad HEAD - strange symbolic ref"
84                         ;;
85                 esac
86         fi
87
88         #
89         # Get rid of any old bisect state.
90         #
91         bisect_clean_state || exit
92
93         #
94         # Check for one bad and then some good revisions.
95         #
96         has_double_dash=0
97         for arg; do
98             case "$arg" in --) has_double_dash=1; break ;; esac
99         done
100         orig_args=$(git rev-parse --sq-quote "$@")
101         bad_seen=0
102         eval=''
103         while [ $# -gt 0 ]; do
104             arg="$1"
105             case "$arg" in
106             --)
107                 shift
108                 break
109                 ;;
110             *)
111                 rev=$(git rev-parse -q --verify "$arg^{commit}") || {
112                     test $has_double_dash -eq 1 &&
113                         die "'$arg' does not appear to be a valid revision"
114                     break
115                 }
116                 case $bad_seen in
117                 0) state='bad' ; bad_seen=1 ;;
118                 *) state='good' ;;
119                 esac
120                 eval="$eval bisect_write '$state' '$rev' 'nolog'; "
121                 shift
122                 ;;
123             esac
124         done
125
126         #
127         # Change state.
128         # In case of mistaken revs or checkout error, or signals received,
129         # "bisect_auto_next" below may exit or misbehave.
130         # We have to trap this to be able to clean up using
131         # "bisect_clean_state".
132         #
133         trap 'bisect_clean_state' 0
134         trap 'exit 255' 1 2 3 15
135
136         #
137         # Write new start state.
138         #
139         echo "$start_head" >"$GIT_DIR/BISECT_START" &&
140         git rev-parse --sq-quote "$@" >"$GIT_DIR/BISECT_NAMES" &&
141         eval "$eval" &&
142         echo "git bisect start$orig_args" >>"$GIT_DIR/BISECT_LOG" || exit
143         #
144         # Check if we can proceed to the next bisect state.
145         #
146         bisect_auto_next
147
148         trap '-' 0
149 }
150
151 bisect_write() {
152         state="$1"
153         rev="$2"
154         nolog="$3"
155         case "$state" in
156                 bad)            tag="$state" ;;
157                 good|skip)      tag="$state"-"$rev" ;;
158                 *)              die "Bad bisect_write argument: $state" ;;
159         esac
160         git update-ref "refs/bisect/$tag" "$rev" || exit
161         echo "# $state: $(git show-branch $rev)" >>"$GIT_DIR/BISECT_LOG"
162         test -n "$nolog" || echo "git bisect $state $rev" >>"$GIT_DIR/BISECT_LOG"
163 }
164
165 is_expected_rev() {
166         test -f "$GIT_DIR/BISECT_EXPECTED_REV" &&
167         test "$1" = $(cat "$GIT_DIR/BISECT_EXPECTED_REV")
168 }
169
170 check_expected_revs() {
171         for _rev in "$@"; do
172                 if ! is_expected_rev "$_rev"; then
173                         rm -f "$GIT_DIR/BISECT_ANCESTORS_OK"
174                         rm -f "$GIT_DIR/BISECT_EXPECTED_REV"
175                         return
176                 fi
177         done
178 }
179
180 bisect_skip() {
181         all=''
182         for arg in "$@"
183         do
184             case "$arg" in
185             *..*)
186                 revs=$(git rev-list "$arg") || die "Bad rev input: $arg" ;;
187             *)
188                 revs=$(git rev-parse --sq-quote "$arg") ;;
189             esac
190             all="$all $revs"
191         done
192         eval bisect_state 'skip' $all
193 }
194
195 bisect_state() {
196         bisect_autostart
197         state=$1
198         case "$#,$state" in
199         0,*)
200                 die "Please call 'bisect_state' with at least one argument." ;;
201         1,bad|1,good|1,skip)
202                 rev=$(git rev-parse --verify HEAD) ||
203                         die "Bad rev input: HEAD"
204                 bisect_write "$state" "$rev"
205                 check_expected_revs "$rev" ;;
206         2,bad|*,good|*,skip)
207                 shift
208                 eval=''
209                 for rev in "$@"
210                 do
211                         sha=$(git rev-parse --verify "$rev^{commit}") ||
212                                 die "Bad rev input: $rev"
213                         eval="$eval bisect_write '$state' '$sha'; "
214                 done
215                 eval "$eval"
216                 check_expected_revs "$@" ;;
217         *,bad)
218                 die "'git bisect bad' can take only one argument." ;;
219         *)
220                 usage ;;
221         esac
222         bisect_auto_next
223 }
224
225 bisect_next_check() {
226         missing_good= missing_bad=
227         git show-ref -q --verify refs/bisect/bad || missing_bad=t
228         test -n "$(git for-each-ref "refs/bisect/good-*")" || missing_good=t
229
230         case "$missing_good,$missing_bad,$1" in
231         ,,*)
232                 : have both good and bad - ok
233                 ;;
234         *,)
235                 # do not have both but not asked to fail - just report.
236                 false
237                 ;;
238         t,,good)
239                 # have bad but not good.  we could bisect although
240                 # this is less optimum.
241                 echo >&2 'Warning: bisecting only with a bad commit.'
242                 if test -t 0
243                 then
244                         printf >&2 'Are you sure [Y/n]? '
245                         read yesno
246                         case "$yesno" in [Nn]*) exit 1 ;; esac
247                 fi
248                 : bisect without good...
249                 ;;
250         *)
251                 THEN=''
252                 test -s "$GIT_DIR/BISECT_START" || {
253                         echo >&2 'You need to start by "git bisect start".'
254                         THEN='then '
255                 }
256                 echo >&2 'You '$THEN'need to give me at least one good' \
257                         'and one bad revisions.'
258                 echo >&2 '(You can use "git bisect bad" and' \
259                         '"git bisect good" for that.)'
260                 exit 1 ;;
261         esac
262 }
263
264 bisect_auto_next() {
265         bisect_next_check && bisect_next || :
266 }
267
268 bisect_next() {
269         case "$#" in 0) ;; *) usage ;; esac
270         bisect_autostart
271         bisect_next_check good
272
273         # Perform all bisection computation, display and checkout
274         git bisect--helper --next-all
275         res=$?
276
277         # Check if we should exit because bisection is finished
278         test $res -eq 10 && exit 0
279
280         # Check for an error in the bisection process
281         test $res -ne 0 && exit $res
282
283         return 0
284 }
285
286 bisect_visualize() {
287         bisect_next_check fail
288
289         if test $# = 0
290         then
291                 case "${DISPLAY+set}${SESSIONNAME+set}${MSYSTEM+set}${SECURITYSESSIONID+set}" in
292                 '')     set git log ;;
293                 set*)   set gitk ;;
294                 esac
295         else
296                 case "$1" in
297                 git*|tig) ;;
298                 -*)     set git log "$@" ;;
299                 *)      set git "$@" ;;
300                 esac
301         fi
302
303         eval '"$@"' --bisect -- $(cat "$GIT_DIR/BISECT_NAMES")
304 }
305
306 bisect_reset() {
307         test -s "$GIT_DIR/BISECT_START" || {
308                 echo "We are not bisecting."
309                 return
310         }
311         case "$#" in
312         0) branch=$(cat "$GIT_DIR/BISECT_START") ;;
313         1) git rev-parse --quiet --verify "$1^{commit}" > /dev/null ||
314                die "'$1' is not a valid commit"
315            branch="$1" ;;
316         *)
317             usage ;;
318         esac
319         git checkout "$branch" -- && bisect_clean_state
320 }
321
322 bisect_clean_state() {
323         # There may be some refs packed during bisection.
324         git for-each-ref --format='%(refname) %(objectname)' refs/bisect/\* |
325         while read ref hash
326         do
327                 git update-ref -d $ref $hash || exit
328         done
329         rm -f "$GIT_DIR/BISECT_EXPECTED_REV" &&
330         rm -f "$GIT_DIR/BISECT_ANCESTORS_OK" &&
331         rm -f "$GIT_DIR/BISECT_LOG" &&
332         rm -f "$GIT_DIR/BISECT_NAMES" &&
333         rm -f "$GIT_DIR/BISECT_RUN" &&
334         # Cleanup head-name if it got left by an old version of git-bisect
335         rm -f "$GIT_DIR/head-name" &&
336
337         rm -f "$GIT_DIR/BISECT_START"
338 }
339
340 bisect_replay () {
341         test -r "$1" || die "cannot read $1 for replaying"
342         bisect_reset
343         while read git bisect command rev
344         do
345                 test "$git $bisect" = "git bisect" -o "$git" = "git-bisect" || continue
346                 if test "$git" = "git-bisect"; then
347                         rev="$command"
348                         command="$bisect"
349                 fi
350                 case "$command" in
351                 start)
352                         cmd="bisect_start $rev"
353                         eval "$cmd" ;;
354                 good|bad|skip)
355                         bisect_write "$command" "$rev" ;;
356                 *)
357                         die "?? what are you talking about?" ;;
358                 esac
359         done <"$1"
360         bisect_auto_next
361 }
362
363 bisect_run () {
364     bisect_next_check fail
365
366     while true
367     do
368       echo "running $@"
369       "$@"
370       res=$?
371
372       # Check for really bad run error.
373       if [ $res -lt 0 -o $res -ge 128 ]; then
374           echo >&2 "bisect run failed:"
375           echo >&2 "exit code $res from '$@' is < 0 or >= 128"
376           exit $res
377       fi
378
379       # Find current state depending on run success or failure.
380       # A special exit code of 125 means cannot test.
381       if [ $res -eq 125 ]; then
382           state='skip'
383       elif [ $res -gt 0 ]; then
384           state='bad'
385       else
386           state='good'
387       fi
388
389       # We have to use a subshell because "bisect_state" can exit.
390       ( bisect_state $state > "$GIT_DIR/BISECT_RUN" )
391       res=$?
392
393       cat "$GIT_DIR/BISECT_RUN"
394
395       if sane_grep "first bad commit could be any of" "$GIT_DIR/BISECT_RUN" \
396                 > /dev/null; then
397           echo >&2 "bisect run cannot continue any more"
398           exit $res
399       fi
400
401       if [ $res -ne 0 ]; then
402           echo >&2 "bisect run failed:"
403           echo >&2 "'bisect_state $state' exited with error code $res"
404           exit $res
405       fi
406
407       if sane_grep "is the first bad commit" "$GIT_DIR/BISECT_RUN" > /dev/null; then
408           echo "bisect run success"
409           exit 0;
410       fi
411
412     done
413 }
414
415
416 case "$#" in
417 0)
418     usage ;;
419 *)
420     cmd="$1"
421     shift
422     case "$cmd" in
423     help)
424         git bisect -h ;;
425     start)
426         bisect_start "$@" ;;
427     bad|good)
428         bisect_state "$cmd" "$@" ;;
429     skip)
430         bisect_skip "$@" ;;
431     next)
432         # Not sure we want "next" at the UI level anymore.
433         bisect_next "$@" ;;
434     visualize|view)
435         bisect_visualize "$@" ;;
436     reset)
437         bisect_reset "$@" ;;
438     replay)
439         bisect_replay "$@" ;;
440     log)
441         cat "$GIT_DIR/BISECT_LOG" ;;
442     run)
443         bisect_run "$@" ;;
444     *)
445         usage ;;
446     esac
447 esac