Merge branch 'maint'
[git] / git-rebase--interactive.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2006 Johannes E. Schindelin
4
5 # SHORT DESCRIPTION
6 #
7 # This script makes it easy to fix up commits in the middle of a series,
8 # and rearrange commits.
9 #
10 # The original idea comes from Eric W. Biederman, in
11 # http://article.gmane.org/gmane.comp.version-control.git/22407
12
13 USAGE='(--continue | --abort | --skip | [--preserve-merges] [--verbose]
14         [--onto <branch>] <upstream> [<branch>])'
15
16 OPTIONS_SPEC=
17 . git-sh-setup
18 require_work_tree
19
20 DOTEST="$GIT_DIR/.dotest-merge"
21 TODO="$DOTEST"/git-rebase-todo
22 DONE="$DOTEST"/done
23 MSG="$DOTEST"/message
24 SQUASH_MSG="$DOTEST"/message-squash
25 REWRITTEN="$DOTEST"/rewritten
26 PRESERVE_MERGES=
27 STRATEGY=
28 VERBOSE=
29 test -d "$REWRITTEN" && PRESERVE_MERGES=t
30 test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
31 test -f "$DOTEST"/verbose && VERBOSE=t
32
33 GIT_CHERRY_PICK_HELP="  After resolving the conflicts,
34 mark the corrected paths with 'git add <paths>', and
35 run 'git rebase --continue'"
36 export GIT_CHERRY_PICK_HELP
37
38 warn () {
39         echo "$*" >&2
40 }
41
42 output () {
43         case "$VERBOSE" in
44         '')
45                 output=$("$@" 2>&1 )
46                 status=$?
47                 test $status != 0 && printf "%s\n" "$output"
48                 return $status
49                 ;;
50         *)
51                 "$@"
52                 ;;
53         esac
54 }
55
56 require_clean_work_tree () {
57         # test if working tree is dirty
58         git rev-parse --verify HEAD > /dev/null &&
59         git update-index --refresh &&
60         git diff-files --quiet &&
61         git diff-index --cached --quiet HEAD -- ||
62         die "Working tree is dirty"
63 }
64
65 ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
66
67 comment_for_reflog () {
68         case "$ORIG_REFLOG_ACTION" in
69         ''|rebase*)
70                 GIT_REFLOG_ACTION="rebase -i ($1)"
71                 export GIT_REFLOG_ACTION
72                 ;;
73         esac
74 }
75
76 mark_action_done () {
77         sed -e 1q < "$TODO" >> "$DONE"
78         sed -e 1d < "$TODO" >> "$TODO".new
79         mv -f "$TODO".new "$TODO"
80         count=$(($(grep -ve '^$' -e '^#' < "$DONE" | wc -l)))
81         total=$(($count+$(grep -ve '^$' -e '^#' < "$TODO" | wc -l)))
82         printf "Rebasing (%d/%d)\r" $count $total
83         test -z "$VERBOSE" || echo
84 }
85
86 make_patch () {
87         parent_sha1=$(git rev-parse --verify "$1"^) ||
88                 die "Cannot get patch for $1^"
89         git diff-tree -p "$parent_sha1".."$1" > "$DOTEST"/patch
90         test -f "$DOTEST"/message ||
91                 git cat-file commit "$1" | sed "1,/^$/d" > "$DOTEST"/message
92         test -f "$DOTEST"/author-script ||
93                 get_author_ident_from_commit "$1" > "$DOTEST"/author-script
94 }
95
96 die_with_patch () {
97         make_patch "$1"
98         git rerere
99         die "$2"
100 }
101
102 die_abort () {
103         rm -rf "$DOTEST"
104         die "$1"
105 }
106
107 has_action () {
108         grep -vqe '^$' -e '^#' "$1"
109 }
110
111 pick_one () {
112         no_ff=
113         case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
114         output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
115         test -d "$REWRITTEN" &&
116                 pick_one_preserving_merges "$@" && return
117         parent_sha1=$(git rev-parse --verify $sha1^) ||
118                 die "Could not get the parent of $sha1"
119         current_sha1=$(git rev-parse --verify HEAD)
120         if test "$no_ff$current_sha1" = "$parent_sha1"; then
121                 output git reset --hard $sha1
122                 test "a$1" = a-n && output git reset --soft $current_sha1
123                 sha1=$(git rev-parse --short $sha1)
124                 output warn Fast forward to $sha1
125         else
126                 output git cherry-pick "$@"
127         fi
128 }
129
130 pick_one_preserving_merges () {
131         case "$1" in -n) sha1=$2 ;; *) sha1=$1 ;; esac
132         sha1=$(git rev-parse $sha1)
133
134         if test -f "$DOTEST"/current-commit
135         then
136                 current_commit=$(cat "$DOTEST"/current-commit) &&
137                 git rev-parse HEAD > "$REWRITTEN"/$current_commit &&
138                 rm "$DOTEST"/current-commit ||
139                 die "Cannot write current commit's replacement sha1"
140         fi
141
142         # rewrite parents; if none were rewritten, we can fast-forward.
143         fast_forward=t
144         preserve=t
145         new_parents=
146         for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -f2-)
147         do
148                 if test -f "$REWRITTEN"/$p
149                 then
150                         preserve=f
151                         new_p=$(cat "$REWRITTEN"/$p)
152                         test $p != $new_p && fast_forward=f
153                         case "$new_parents" in
154                         *$new_p*)
155                                 ;; # do nothing; that parent is already there
156                         *)
157                                 new_parents="$new_parents $new_p"
158                                 ;;
159                         esac
160                 fi
161         done
162         case $fast_forward in
163         t)
164                 output warn "Fast forward to $sha1"
165                 test $preserve = f || echo $sha1 > "$REWRITTEN"/$sha1
166                 ;;
167         f)
168                 test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
169
170                 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
171                 # detach HEAD to current parent
172                 output git checkout $first_parent 2> /dev/null ||
173                         die "Cannot move HEAD to $first_parent"
174
175                 echo $sha1 > "$DOTEST"/current-commit
176                 case "$new_parents" in
177                 ' '*' '*)
178                         # redo merge
179                         author_script=$(get_author_ident_from_commit $sha1)
180                         eval "$author_script"
181                         msg="$(git cat-file commit $sha1 | sed -e '1,/^$/d')"
182                         # No point in merging the first parent, that's HEAD
183                         new_parents=${new_parents# $first_parent}
184                         if ! GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
185                                 GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
186                                 GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
187                                 output git merge $STRATEGY -m "$msg" \
188                                         $new_parents
189                         then
190                                 git rerere
191                                 printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
192                                 die Error redoing merge $sha1
193                         fi
194                         ;;
195                 *)
196                         output git cherry-pick "$@" ||
197                                 die_with_patch $sha1 "Could not pick $sha1"
198                         ;;
199                 esac
200                 ;;
201         esac
202 }
203
204 nth_string () {
205         case "$1" in
206         *1[0-9]|*[04-9]) echo "$1"th;;
207         *1) echo "$1"st;;
208         *2) echo "$1"nd;;
209         *3) echo "$1"rd;;
210         esac
211 }
212
213 make_squash_message () {
214         if test -f "$SQUASH_MSG"; then
215                 COUNT=$(($(sed -n "s/^# This is [^0-9]*\([1-9][0-9]*\).*/\1/p" \
216                         < "$SQUASH_MSG" | tail -n 1)+1))
217                 echo "# This is a combination of $COUNT commits."
218                 sed -n "2,\$p" < "$SQUASH_MSG"
219         else
220                 COUNT=2
221                 echo "# This is a combination of two commits."
222                 echo "# The first commit's message is:"
223                 echo
224                 git cat-file commit HEAD | sed -e '1,/^$/d'
225                 echo
226         fi
227         echo "# This is the $(nth_string $COUNT) commit message:"
228         echo
229         git cat-file commit $1 | sed -e '1,/^$/d'
230 }
231
232 peek_next_command () {
233         sed -n "1s/ .*$//p" < "$TODO"
234 }
235
236 do_next () {
237         rm -f "$DOTEST"/message "$DOTEST"/author-script \
238                 "$DOTEST"/amend || exit
239         read command sha1 rest < "$TODO"
240         case "$command" in
241         '#'*|'')
242                 mark_action_done
243                 ;;
244         pick|p)
245                 comment_for_reflog pick
246
247                 mark_action_done
248                 pick_one $sha1 ||
249                         die_with_patch $sha1 "Could not apply $sha1... $rest"
250                 ;;
251         edit|e)
252                 comment_for_reflog edit
253
254                 mark_action_done
255                 pick_one $sha1 ||
256                         die_with_patch $sha1 "Could not apply $sha1... $rest"
257                 make_patch $sha1
258                 : > "$DOTEST"/amend
259                 warn
260                 warn "You can amend the commit now, with"
261                 warn
262                 warn "  git commit --amend"
263                 warn
264                 exit 0
265                 ;;
266         squash|s)
267                 comment_for_reflog squash
268
269                 has_action "$DONE" ||
270                         die "Cannot 'squash' without a previous commit"
271
272                 mark_action_done
273                 make_squash_message $sha1 > "$MSG"
274                 case "$(peek_next_command)" in
275                 squash|s)
276                         EDIT_COMMIT=
277                         USE_OUTPUT=output
278                         cp "$MSG" "$SQUASH_MSG"
279                         ;;
280                 *)
281                         EDIT_COMMIT=-e
282                         USE_OUTPUT=
283                         rm -f "$SQUASH_MSG" || exit
284                         ;;
285                 esac
286
287                 failed=f
288                 author_script=$(get_author_ident_from_commit HEAD)
289                 output git reset --soft HEAD^
290                 pick_one -n $sha1 || failed=t
291                 echo "$author_script" > "$DOTEST"/author-script
292                 case $failed in
293                 f)
294                         # This is like --amend, but with a different message
295                         eval "$author_script"
296                         GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
297                         GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
298                         GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
299                         $USE_OUTPUT git commit -F "$MSG" $EDIT_COMMIT
300                         ;;
301                 t)
302                         cp "$MSG" "$GIT_DIR"/MERGE_MSG
303                         warn
304                         warn "Could not apply $sha1... $rest"
305                         die_with_patch $sha1 ""
306                         ;;
307                 esac
308                 ;;
309         *)
310                 warn "Unknown command: $command $sha1 $rest"
311                 die_with_patch $sha1 "Please fix this in the file $TODO."
312                 ;;
313         esac
314         test -s "$TODO" && return
315
316         comment_for_reflog finish &&
317         HEADNAME=$(cat "$DOTEST"/head-name) &&
318         OLDHEAD=$(cat "$DOTEST"/head) &&
319         SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
320         if test -d "$REWRITTEN"
321         then
322                 test -f "$DOTEST"/current-commit &&
323                         current_commit=$(cat "$DOTEST"/current-commit) &&
324                         git rev-parse HEAD > "$REWRITTEN"/$current_commit
325                 NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
326         else
327                 NEWHEAD=$(git rev-parse HEAD)
328         fi &&
329         case $HEADNAME in
330         refs/*)
331                 message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
332                 git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
333                 git symbolic-ref HEAD $HEADNAME
334                 ;;
335         esac && {
336                 test ! -f "$DOTEST"/verbose ||
337                         git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
338         } &&
339         rm -rf "$DOTEST" &&
340         git gc --auto &&
341         warn "Successfully rebased and updated $HEADNAME."
342
343         exit
344 }
345
346 do_rest () {
347         while :
348         do
349                 do_next
350         done
351 }
352
353 while test $# != 0
354 do
355         case "$1" in
356         --continue)
357                 comment_for_reflog continue
358
359                 test -d "$DOTEST" || die "No interactive rebase running"
360
361                 # commit if necessary
362                 git rev-parse --verify HEAD > /dev/null &&
363                 git update-index --refresh &&
364                 git diff-files --quiet &&
365                 ! git diff-index --cached --quiet HEAD -- &&
366                 . "$DOTEST"/author-script && {
367                         test ! -f "$DOTEST"/amend || git reset --soft HEAD^
368                 } &&
369                 export GIT_AUTHOR_NAME GIT_AUTHOR_NAME GIT_AUTHOR_DATE &&
370                 git commit -F "$DOTEST"/message -e
371
372                 require_clean_work_tree
373                 do_rest
374                 ;;
375         --abort)
376                 comment_for_reflog abort
377
378                 git rerere clear
379                 test -d "$DOTEST" || die "No interactive rebase running"
380
381                 HEADNAME=$(cat "$DOTEST"/head-name)
382                 HEAD=$(cat "$DOTEST"/head)
383                 case $HEADNAME in
384                 refs/*)
385                         git symbolic-ref HEAD $HEADNAME
386                         ;;
387                 esac &&
388                 output git reset --hard $HEAD &&
389                 rm -rf "$DOTEST"
390                 exit
391                 ;;
392         --skip)
393                 comment_for_reflog skip
394
395                 git rerere clear
396                 test -d "$DOTEST" || die "No interactive rebase running"
397
398                 output git reset --hard && do_rest
399                 ;;
400         -s|--strategy)
401                 case "$#,$1" in
402                 *,*=*)
403                         STRATEGY="-s "$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
404                 1,*)
405                         usage ;;
406                 *)
407                         STRATEGY="-s $2"
408                         shift ;;
409                 esac
410                 ;;
411         --merge)
412                 # we use merge anyway
413                 ;;
414         -C*)
415                 die "Interactive rebase uses merge, so $1 does not make sense"
416                 ;;
417         -v|--verbose)
418                 VERBOSE=t
419                 ;;
420         -p|--preserve-merges)
421                 PRESERVE_MERGES=t
422                 ;;
423         -i|--interactive)
424                 # yeah, we know
425                 ;;
426         ''|-h)
427                 usage
428                 ;;
429         *)
430                 test -d "$DOTEST" &&
431                         die "Interactive rebase already started"
432
433                 git var GIT_COMMITTER_IDENT >/dev/null ||
434                         die "You need to set your committer info first"
435
436                 comment_for_reflog start
437
438                 ONTO=
439                 case "$1" in
440                 --onto)
441                         ONTO=$(git rev-parse --verify "$2") ||
442                                 die "Does not point to a valid commit: $2"
443                         shift; shift
444                         ;;
445                 esac
446
447                 require_clean_work_tree
448
449                 if test ! -z "$2"
450                 then
451                         output git show-ref --verify --quiet "refs/heads/$2" ||
452                                 die "Invalid branchname: $2"
453                         output git checkout "$2" ||
454                                 die "Could not checkout $2"
455                 fi
456
457                 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
458                 UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
459
460                 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
461
462                 test -z "$ONTO" && ONTO=$UPSTREAM
463
464                 : > "$DOTEST"/interactive || die "Could not mark as interactive"
465                 git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
466                         echo "detached HEAD" > "$DOTEST"/head-name
467
468                 echo $HEAD > "$DOTEST"/head
469                 echo $UPSTREAM > "$DOTEST"/upstream
470                 echo $ONTO > "$DOTEST"/onto
471                 test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
472                 test t = "$VERBOSE" && : > "$DOTEST"/verbose
473                 if test t = "$PRESERVE_MERGES"
474                 then
475                         # $REWRITTEN contains files for each commit that is
476                         # reachable by at least one merge base of $HEAD and
477                         # $UPSTREAM. They are not necessarily rewritten, but
478                         # their children might be.
479                         # This ensures that commits on merged, but otherwise
480                         # unrelated side branches are left alone. (Think "X"
481                         # in the man page's example.)
482                         mkdir "$REWRITTEN" &&
483                         for c in $(git merge-base --all $HEAD $UPSTREAM)
484                         do
485                                 echo $ONTO > "$REWRITTEN"/$c ||
486                                         die "Could not init rewritten commits"
487                         done
488                         MERGES_OPTION=
489                 else
490                         MERGES_OPTION=--no-merges
491                 fi
492
493                 SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
494                 SHORTHEAD=$(git rev-parse --short $HEAD)
495                 SHORTONTO=$(git rev-parse --short $ONTO)
496                 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
497                         --abbrev=7 --reverse --left-right --cherry-pick \
498                         $UPSTREAM...$HEAD | \
499                         sed -n "s/^>/pick /p" > "$TODO"
500                 cat >> "$TODO" << EOF
501
502 # Rebase $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
503 #
504 # Commands:
505 #  pick = use commit
506 #  edit = use commit, but stop for amending
507 #  squash = use commit, but meld into previous commit
508 #
509 # If you remove a line here THAT COMMIT WILL BE LOST.
510 # However, if you remove everything, the rebase will be aborted.
511 #
512 EOF
513
514                 has_action "$TODO" ||
515                         die_abort "Nothing to do"
516
517                 cp "$TODO" "$TODO".backup
518                 git_editor "$TODO" ||
519                         die "Could not execute editor"
520
521                 has_action "$TODO" ||
522                         die_abort "Nothing to do"
523
524                 output git checkout $ONTO && do_rest
525                 ;;
526         esac
527         shift
528 done