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