Merge branch 'ms/commit-cc-option-helpstring' into 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 . git-sh-setup
14
15 # The file containing rebase commands, comments, and empty lines.
16 # This file is created by "git rebase -i" then edited by the user.  As
17 # the lines are processed, they are removed from the front of this
18 # file and written to the tail of $done.
19 todo="$state_dir"/git-rebase-todo
20
21 # The rebase command lines that have already been processed.  A line
22 # is moved here when it is first handled, before any associated user
23 # actions.
24 done="$state_dir"/done
25
26 # The commit message that is planned to be used for any changes that
27 # need to be committed following a user interaction.
28 msg="$state_dir"/message
29
30 # The file into which is accumulated the suggested commit message for
31 # squash/fixup commands.  When the first of a series of squash/fixups
32 # is seen, the file is created and the commit message from the
33 # previous commit and from the first squash/fixup commit are written
34 # to it.  The commit message for each subsequent squash/fixup commit
35 # is appended to the file as it is processed.
36 #
37 # The first line of the file is of the form
38 #     # This is a combination of $count commits.
39 # where $count is the number of commits whose messages have been
40 # written to the file so far (including the initial "pick" commit).
41 # Each time that a commit message is processed, this line is read and
42 # updated.  It is deleted just before the combined commit is made.
43 squash_msg="$state_dir"/message-squash
44
45 # If the current series of squash/fixups has not yet included a squash
46 # command, then this file exists and holds the commit message of the
47 # original "pick" commit.  (If the series ends without a "squash"
48 # command, then this can be used as the commit message of the combined
49 # commit without opening the editor.)
50 fixup_msg="$state_dir"/message-fixup
51
52 # $rewritten is the name of a directory containing files for each
53 # commit that is reachable by at least one merge base of $head and
54 # $upstream. They are not necessarily rewritten, but their children
55 # might be.  This ensures that commits on merged, but otherwise
56 # unrelated side branches are left alone. (Think "X" in the man page's
57 # example.)
58 rewritten="$state_dir"/rewritten
59
60 dropped="$state_dir"/dropped
61
62 # A script to set the GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
63 # GIT_AUTHOR_DATE that will be used for the commit that is currently
64 # being rebased.
65 author_script="$state_dir"/author-script
66
67 # When an "edit" rebase command is being processed, the SHA1 of the
68 # commit to be edited is recorded in this file.  When "git rebase
69 # --continue" is executed, if there are any staged changes then they
70 # will be amended to the HEAD commit, but only provided the HEAD
71 # commit is still the commit to be edited.  When any other rebase
72 # command is processed, this file is deleted.
73 amend="$state_dir"/amend
74
75 # For the post-rewrite hook, we make a list of rewritten commits and
76 # their new sha1s.  The rewritten-pending list keeps the sha1s of
77 # commits that have been processed, but not committed yet,
78 # e.g. because they are waiting for a 'squash' command.
79 rewritten_list="$state_dir"/rewritten-list
80 rewritten_pending="$state_dir"/rewritten-pending
81
82 GIT_CHERRY_PICK_HELP="$resolvemsg"
83 export GIT_CHERRY_PICK_HELP
84
85 warn () {
86         printf '%s\n' "$*" >&2
87 }
88
89 # Output the commit message for the specified commit.
90 commit_message () {
91         git cat-file commit "$1" | sed "1,/^$/d"
92 }
93
94 orig_reflog_action="$GIT_REFLOG_ACTION"
95
96 comment_for_reflog () {
97         case "$orig_reflog_action" in
98         ''|rebase*)
99                 GIT_REFLOG_ACTION="rebase -i ($1)"
100                 export GIT_REFLOG_ACTION
101                 ;;
102         esac
103 }
104
105 last_count=
106 mark_action_done () {
107         sed -e 1q < "$todo" >> "$done"
108         sed -e 1d < "$todo" >> "$todo".new
109         mv -f "$todo".new "$todo"
110         new_count=$(sane_grep -c '^[^#]' < "$done")
111         total=$(($new_count+$(sane_grep -c '^[^#]' < "$todo")))
112         if test "$last_count" != "$new_count"
113         then
114                 last_count=$new_count
115                 printf "Rebasing (%d/%d)\r" $new_count $total
116                 test -z "$verbose" || echo
117         fi
118 }
119
120 make_patch () {
121         sha1_and_parents="$(git rev-list --parents -1 "$1")"
122         case "$sha1_and_parents" in
123         ?*' '?*' '?*)
124                 git diff --cc $sha1_and_parents
125                 ;;
126         ?*' '?*)
127                 git diff-tree -p "$1^!"
128                 ;;
129         *)
130                 echo "Root commit"
131                 ;;
132         esac > "$state_dir"/patch
133         test -f "$msg" ||
134                 commit_message "$1" > "$msg"
135         test -f "$author_script" ||
136                 get_author_ident_from_commit "$1" > "$author_script"
137 }
138
139 die_with_patch () {
140         echo "$1" > "$state_dir"/stopped-sha
141         make_patch "$1"
142         git rerere
143         die "$2"
144 }
145
146 die_abort () {
147         rm -rf "$state_dir"
148         die "$1"
149 }
150
151 has_action () {
152         sane_grep '^[^#]' "$1" >/dev/null
153 }
154
155 # Run command with GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
156 # GIT_AUTHOR_DATE exported from the current environment.
157 do_with_author () {
158         (
159                 export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
160                 "$@"
161         )
162 }
163
164 git_sequence_editor () {
165         if test -z "$GIT_SEQUENCE_EDITOR"
166         then
167                 GIT_SEQUENCE_EDITOR="$(git config sequence.editor)"
168                 if [ -z "$GIT_SEQUENCE_EDITOR" ]
169                 then
170                         GIT_SEQUENCE_EDITOR="$(git var GIT_EDITOR)" || return $?
171                 fi
172         fi
173
174         eval "$GIT_SEQUENCE_EDITOR" '"$@"'
175 }
176
177 pick_one () {
178         ff=--ff
179         case "$1" in -n) sha1=$2; ff= ;; *) sha1=$1 ;; esac
180         case "$force_rebase" in '') ;; ?*) ff= ;; esac
181         output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
182         test -d "$rewritten" &&
183                 pick_one_preserving_merges "$@" && return
184         output git cherry-pick $ff "$@"
185 }
186
187 pick_one_preserving_merges () {
188         fast_forward=t
189         case "$1" in
190         -n)
191                 fast_forward=f
192                 sha1=$2
193                 ;;
194         *)
195                 sha1=$1
196                 ;;
197         esac
198         sha1=$(git rev-parse $sha1)
199
200         if test -f "$state_dir"/current-commit
201         then
202                 if test "$fast_forward" = t
203                 then
204                         while read current_commit
205                         do
206                                 git rev-parse HEAD > "$rewritten"/$current_commit
207                         done <"$state_dir"/current-commit
208                         rm "$state_dir"/current-commit ||
209                         die "Cannot write current commit's replacement sha1"
210                 fi
211         fi
212
213         echo $sha1 >> "$state_dir"/current-commit
214
215         # rewrite parents; if none were rewritten, we can fast-forward.
216         new_parents=
217         pend=" $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)"
218         if test "$pend" = " "
219         then
220                 pend=" root"
221         fi
222         while [ "$pend" != "" ]
223         do
224                 p=$(expr "$pend" : ' \([^ ]*\)')
225                 pend="${pend# $p}"
226
227                 if test -f "$rewritten"/$p
228                 then
229                         new_p=$(cat "$rewritten"/$p)
230
231                         # If the todo reordered commits, and our parent is marked for
232                         # rewriting, but hasn't been gotten to yet, assume the user meant to
233                         # drop it on top of the current HEAD
234                         if test -z "$new_p"
235                         then
236                                 new_p=$(git rev-parse HEAD)
237                         fi
238
239                         test $p != $new_p && fast_forward=f
240                         case "$new_parents" in
241                         *$new_p*)
242                                 ;; # do nothing; that parent is already there
243                         *)
244                                 new_parents="$new_parents $new_p"
245                                 ;;
246                         esac
247                 else
248                         if test -f "$dropped"/$p
249                         then
250                                 fast_forward=f
251                                 replacement="$(cat "$dropped"/$p)"
252                                 test -z "$replacement" && replacement=root
253                                 pend=" $replacement$pend"
254                         else
255                                 new_parents="$new_parents $p"
256                         fi
257                 fi
258         done
259         case $fast_forward in
260         t)
261                 output warn "Fast-forward to $sha1"
262                 output git reset --hard $sha1 ||
263                         die "Cannot fast-forward to $sha1"
264                 ;;
265         f)
266                 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
267
268                 if [ "$1" != "-n" ]
269                 then
270                         # detach HEAD to current parent
271                         output git checkout $first_parent 2> /dev/null ||
272                                 die "Cannot move HEAD to $first_parent"
273                 fi
274
275                 case "$new_parents" in
276                 ' '*' '*)
277                         test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
278
279                         # redo merge
280                         author_script_content=$(get_author_ident_from_commit $sha1)
281                         eval "$author_script_content"
282                         msg_content="$(commit_message $sha1)"
283                         # No point in merging the first parent, that's HEAD
284                         new_parents=${new_parents# $first_parent}
285                         if ! do_with_author output \
286                                 git merge --no-ff ${strategy:+-s $strategy} -m \
287                                         "$msg_content" $new_parents
288                         then
289                                 printf "%s\n" "$msg_content" > "$GIT_DIR"/MERGE_MSG
290                                 die_with_patch $sha1 "Error redoing merge $sha1"
291                         fi
292                         echo "$sha1 $(git rev-parse HEAD^0)" >> "$rewritten_list"
293                         ;;
294                 *)
295                         output git cherry-pick "$@" ||
296                                 die_with_patch $sha1 "Could not pick $sha1"
297                         ;;
298                 esac
299                 ;;
300         esac
301 }
302
303 nth_string () {
304         case "$1" in
305         *1[0-9]|*[04-9]) echo "$1"th;;
306         *1) echo "$1"st;;
307         *2) echo "$1"nd;;
308         *3) echo "$1"rd;;
309         esac
310 }
311
312 update_squash_messages () {
313         if test -f "$squash_msg"; then
314                 mv "$squash_msg" "$squash_msg".bak || exit
315                 count=$(($(sed -n \
316                         -e "1s/^# This is a combination of \(.*\) commits\./\1/p" \
317                         -e "q" < "$squash_msg".bak)+1))
318                 {
319                         echo "# This is a combination of $count commits."
320                         sed -e 1d -e '2,/^./{
321                                 /^$/d
322                         }' <"$squash_msg".bak
323                 } >"$squash_msg"
324         else
325                 commit_message HEAD > "$fixup_msg" || die "Cannot write $fixup_msg"
326                 count=2
327                 {
328                         echo "# This is a combination of 2 commits."
329                         echo "# The first commit's message is:"
330                         echo
331                         cat "$fixup_msg"
332                 } >"$squash_msg"
333         fi
334         case $1 in
335         squash)
336                 rm -f "$fixup_msg"
337                 echo
338                 echo "# This is the $(nth_string $count) commit message:"
339                 echo
340                 commit_message $2
341                 ;;
342         fixup)
343                 echo
344                 echo "# The $(nth_string $count) commit message will be skipped:"
345                 echo
346                 commit_message $2 | sed -e 's/^/#       /'
347                 ;;
348         esac >>"$squash_msg"
349 }
350
351 peek_next_command () {
352         sed -n -e "/^#/d" -e '/^$/d' -e "s/ .*//p" -e "q" < "$todo"
353 }
354
355 # A squash/fixup has failed.  Prepare the long version of the squash
356 # commit message, then die_with_patch.  This code path requires the
357 # user to edit the combined commit message for all commits that have
358 # been squashed/fixedup so far.  So also erase the old squash
359 # messages, effectively causing the combined commit to be used as the
360 # new basis for any further squash/fixups.  Args: sha1 rest
361 die_failed_squash() {
362         mv "$squash_msg" "$msg" || exit
363         rm -f "$fixup_msg"
364         cp "$msg" "$GIT_DIR"/MERGE_MSG || exit
365         warn
366         warn "Could not apply $1... $2"
367         die_with_patch $1 ""
368 }
369
370 flush_rewritten_pending() {
371         test -s "$rewritten_pending" || return
372         newsha1="$(git rev-parse HEAD^0)"
373         sed "s/$/ $newsha1/" < "$rewritten_pending" >> "$rewritten_list"
374         rm -f "$rewritten_pending"
375 }
376
377 record_in_rewritten() {
378         oldsha1="$(git rev-parse $1)"
379         echo "$oldsha1" >> "$rewritten_pending"
380
381         case "$(peek_next_command)" in
382         squash|s|fixup|f)
383                 ;;
384         *)
385                 flush_rewritten_pending
386                 ;;
387         esac
388 }
389
390 do_next () {
391         rm -f "$msg" "$author_script" "$amend" || exit
392         read -r command sha1 rest < "$todo"
393         case "$command" in
394         '#'*|''|noop)
395                 mark_action_done
396                 ;;
397         pick|p)
398                 comment_for_reflog pick
399
400                 mark_action_done
401                 pick_one $sha1 ||
402                         die_with_patch $sha1 "Could not apply $sha1... $rest"
403                 record_in_rewritten $sha1
404                 ;;
405         reword|r)
406                 comment_for_reflog reword
407
408                 mark_action_done
409                 pick_one $sha1 ||
410                         die_with_patch $sha1 "Could not apply $sha1... $rest"
411                 git commit --amend --no-post-rewrite
412                 record_in_rewritten $sha1
413                 ;;
414         edit|e)
415                 comment_for_reflog edit
416
417                 mark_action_done
418                 pick_one $sha1 ||
419                         die_with_patch $sha1 "Could not apply $sha1... $rest"
420                 echo "$sha1" > "$state_dir"/stopped-sha
421                 make_patch $sha1
422                 git rev-parse --verify HEAD > "$amend"
423                 warn "Stopped at $sha1... $rest"
424                 warn "You can amend the commit now, with"
425                 warn
426                 warn "  git commit --amend"
427                 warn
428                 warn "Once you are satisfied with your changes, run"
429                 warn
430                 warn "  git rebase --continue"
431                 warn
432                 exit 0
433                 ;;
434         squash|s|fixup|f)
435                 case "$command" in
436                 squash|s)
437                         squash_style=squash
438                         ;;
439                 fixup|f)
440                         squash_style=fixup
441                         ;;
442                 esac
443                 comment_for_reflog $squash_style
444
445                 test -f "$done" && has_action "$done" ||
446                         die "Cannot '$squash_style' without a previous commit"
447
448                 mark_action_done
449                 update_squash_messages $squash_style $sha1
450                 author_script_content=$(get_author_ident_from_commit HEAD)
451                 echo "$author_script_content" > "$author_script"
452                 eval "$author_script_content"
453                 output git reset --soft HEAD^
454                 pick_one -n $sha1 || die_failed_squash $sha1 "$rest"
455                 case "$(peek_next_command)" in
456                 squash|s|fixup|f)
457                         # This is an intermediate commit; its message will only be
458                         # used in case of trouble.  So use the long version:
459                         do_with_author output git commit --no-verify -F "$squash_msg" ||
460                                 die_failed_squash $sha1 "$rest"
461                         ;;
462                 *)
463                         # This is the final command of this squash/fixup group
464                         if test -f "$fixup_msg"
465                         then
466                                 do_with_author git commit --no-verify -F "$fixup_msg" ||
467                                         die_failed_squash $sha1 "$rest"
468                         else
469                                 cp "$squash_msg" "$GIT_DIR"/SQUASH_MSG || exit
470                                 rm -f "$GIT_DIR"/MERGE_MSG
471                                 do_with_author git commit --no-verify -e ||
472                                         die_failed_squash $sha1 "$rest"
473                         fi
474                         rm -f "$squash_msg" "$fixup_msg"
475                         ;;
476                 esac
477                 record_in_rewritten $sha1
478                 ;;
479         x|"exec")
480                 read -r command rest < "$todo"
481                 mark_action_done
482                 printf 'Executing: %s\n' "$rest"
483                 # "exec" command doesn't take a sha1 in the todo-list.
484                 # => can't just use $sha1 here.
485                 git rev-parse --verify HEAD > "$state_dir"/stopped-sha
486                 ${SHELL:-@SHELL_PATH@} -c "$rest" # Actual execution
487                 status=$?
488                 # Run in subshell because require_clean_work_tree can die.
489                 dirty=f
490                 (require_clean_work_tree "rebase" 2>/dev/null) || dirty=t
491                 if test "$status" -ne 0
492                 then
493                         warn "Execution failed: $rest"
494                         test "$dirty" = f ||
495                         warn "and made changes to the index and/or the working tree"
496
497                         warn "You can fix the problem, and then run"
498                         warn
499                         warn "  git rebase --continue"
500                         warn
501                         exit "$status"
502                 elif test "$dirty" = t
503                 then
504                         warn "Execution succeeded: $rest"
505                         warn "but left changes to the index and/or the working tree"
506                         warn "Commit or stash your changes, and then run"
507                         warn
508                         warn "  git rebase --continue"
509                         warn
510                         exit 1
511                 fi
512                 ;;
513         *)
514                 warn "Unknown command: $command $sha1 $rest"
515                 if git rev-parse --verify -q "$sha1" >/dev/null
516                 then
517                         die_with_patch $sha1 "Please fix this in the file $todo."
518                 else
519                         die "Please fix this in the file $todo."
520                 fi
521                 ;;
522         esac
523         test -s "$todo" && return
524
525         comment_for_reflog finish &&
526         shortonto=$(git rev-parse --short $onto) &&
527         newhead=$(git rev-parse HEAD) &&
528         case $head_name in
529         refs/*)
530                 message="$GIT_REFLOG_ACTION: $head_name onto $shortonto" &&
531                 git update-ref -m "$message" $head_name $newhead $orig_head &&
532                 git symbolic-ref \
533                   -m "$GIT_REFLOG_ACTION: returning to $head_name" \
534                   HEAD $head_name
535                 ;;
536         esac && {
537                 test ! -f "$state_dir"/verbose ||
538                         git diff-tree --stat $orig_head..HEAD
539         } &&
540         {
541                 test -s "$rewritten_list" &&
542                 git notes copy --for-rewrite=rebase < "$rewritten_list" ||
543                 true # we don't care if this copying failed
544         } &&
545         if test -x "$GIT_DIR"/hooks/post-rewrite &&
546                 test -s "$rewritten_list"; then
547                 "$GIT_DIR"/hooks/post-rewrite rebase < "$rewritten_list"
548                 true # we don't care if this hook failed
549         fi &&
550         rm -rf "$state_dir" &&
551         git gc --auto &&
552         warn "Successfully rebased and updated $head_name."
553
554         exit
555 }
556
557 do_rest () {
558         while :
559         do
560                 do_next
561         done
562 }
563
564 # skip picking commits whose parents are unchanged
565 skip_unnecessary_picks () {
566         fd=3
567         while read -r command rest
568         do
569                 # fd=3 means we skip the command
570                 case "$fd,$command" in
571                 3,pick|3,p)
572                         # pick a commit whose parent is current $onto -> skip
573                         sha1=${rest%% *}
574                         case "$(git rev-parse --verify --quiet "$sha1"^)" in
575                         "$onto"*)
576                                 onto=$sha1
577                                 ;;
578                         *)
579                                 fd=1
580                                 ;;
581                         esac
582                         ;;
583                 3,#*|3,)
584                         # copy comments
585                         ;;
586                 *)
587                         fd=1
588                         ;;
589                 esac
590                 printf '%s\n' "$command${rest:+ }$rest" >&$fd
591         done <"$todo" >"$todo.new" 3>>"$done" &&
592         mv -f "$todo".new "$todo" &&
593         case "$(peek_next_command)" in
594         squash|s|fixup|f)
595                 record_in_rewritten "$onto"
596                 ;;
597         esac ||
598         die "Could not skip unnecessary pick commands"
599 }
600
601 # Rearrange the todo list that has both "pick sha1 msg" and
602 # "pick sha1 fixup!/squash! msg" appears in it so that the latter
603 # comes immediately after the former, and change "pick" to
604 # "fixup"/"squash".
605 rearrange_squash () {
606         # extract fixup!/squash! lines and resolve any referenced sha1's
607         while read -r pick sha1 message
608         do
609                 case "$message" in
610                 "squash! "*|"fixup! "*)
611                         action="${message%%!*}"
612                         rest="${message#*! }"
613                         echo "$sha1 $action $rest"
614                         # if it's a single word, try to resolve to a full sha1 and
615                         # emit a second copy. This allows us to match on both message
616                         # and on sha1 prefix
617                         if test "${rest#* }" = "$rest"; then
618                                 fullsha="$(git rev-parse -q --verify "$rest" 2>/dev/null)"
619                                 if test -n "$fullsha"; then
620                                         # prefix the action to uniquely identify this line as
621                                         # intended for full sha1 match
622                                         echo "$sha1 +$action $fullsha"
623                                 fi
624                         fi
625                 esac
626         done >"$1.sq" <"$1"
627         test -s "$1.sq" || return
628
629         used=
630         while read -r pick sha1 message
631         do
632                 case " $used" in
633                 *" $sha1 "*) continue ;;
634                 esac
635                 printf '%s\n' "$pick $sha1 $message"
636                 used="$used$sha1 "
637                 while read -r squash action msg_content
638                 do
639                         case " $used" in
640                         *" $squash "*) continue ;;
641                         esac
642                         emit=0
643                         case "$action" in
644                         +*)
645                                 action="${action#+}"
646                                 # full sha1 prefix test
647                                 case "$msg_content" in "$sha1"*) emit=1;; esac ;;
648                         *)
649                                 # message prefix test
650                                 case "$message" in "$msg_content"*) emit=1;; esac ;;
651                         esac
652                         if test $emit = 1; then
653                                 printf '%s\n' "$action $squash $action! $msg_content"
654                                 used="$used$squash "
655                         fi
656                 done <"$1.sq"
657         done >"$1.rearranged" <"$1"
658         cat "$1.rearranged" >"$1"
659         rm -f "$1.sq" "$1.rearranged"
660 }
661
662 case "$action" in
663 continue)
664         # do we have anything to commit?
665         if git diff-index --cached --quiet --ignore-submodules HEAD --
666         then
667                 : Nothing to commit -- skip this
668         else
669                 if ! test -f "$author_script"
670                 then
671                         die "You have staged changes in your working tree. If these changes are meant to be
672 squashed into the previous commit, run:
673
674   git commit --amend
675
676 If they are meant to go into a new commit, run:
677
678   git commit
679
680 In both case, once you're done, continue with:
681
682   git rebase --continue
683 "
684                 fi
685                 . "$author_script" ||
686                         die "Error trying to find the author identity to amend commit"
687                 current_head=
688                 if test -f "$amend"
689                 then
690                         current_head=$(git rev-parse --verify HEAD)
691                         test "$current_head" = $(cat "$amend") ||
692                         die "\
693 You have uncommitted changes in your working tree. Please, commit them
694 first and then run 'git rebase --continue' again."
695                         git reset --soft HEAD^ ||
696                         die "Cannot rewind the HEAD"
697                 fi
698                 do_with_author git commit --no-verify -F "$msg" -e || {
699                         test -n "$current_head" && git reset --soft $current_head
700                         die "Could not commit staged changes."
701                 }
702         fi
703
704         record_in_rewritten "$(cat "$state_dir"/stopped-sha)"
705
706         require_clean_work_tree "rebase"
707         do_rest
708         ;;
709 skip)
710         git rerere clear
711
712         do_rest
713         ;;
714 esac
715
716 git var GIT_COMMITTER_IDENT >/dev/null ||
717         die "You need to set your committer info first"
718
719 comment_for_reflog start
720
721 if test ! -z "$switch_to"
722 then
723         output git checkout "$switch_to" -- ||
724                 die "Could not checkout $switch_to"
725 fi
726
727 orig_head=$(git rev-parse --verify HEAD) || die "No HEAD?"
728 mkdir "$state_dir" || die "Could not create temporary $state_dir"
729
730 : > "$state_dir"/interactive || die "Could not mark as interactive"
731 write_basic_state
732 if test t = "$preserve_merges"
733 then
734         if test -z "$rebase_root"
735         then
736                 mkdir "$rewritten" &&
737                 for c in $(git merge-base --all $orig_head $upstream)
738                 do
739                         echo $onto > "$rewritten"/$c ||
740                                 die "Could not init rewritten commits"
741                 done
742         else
743                 mkdir "$rewritten" &&
744                 echo $onto > "$rewritten"/root ||
745                         die "Could not init rewritten commits"
746         fi
747         # No cherry-pick because our first pass is to determine
748         # parents to rewrite and skipping dropped commits would
749         # prematurely end our probe
750         merges_option=
751 else
752         merges_option="--no-merges --cherry-pick"
753 fi
754
755 shorthead=$(git rev-parse --short $orig_head)
756 shortonto=$(git rev-parse --short $onto)
757 if test -z "$rebase_root"
758         # this is now equivalent to ! -z "$upstream"
759 then
760         shortupstream=$(git rev-parse --short $upstream)
761         revisions=$upstream...$orig_head
762         shortrevisions=$shortupstream..$shorthead
763 else
764         revisions=$onto...$orig_head
765         shortrevisions=$shorthead
766 fi
767 git rev-list $merges_option --pretty=oneline --abbrev-commit \
768         --abbrev=7 --reverse --left-right --topo-order \
769         $revisions | \
770         sed -n "s/^>//p" |
771 while read -r shortsha1 rest
772 do
773         if test t != "$preserve_merges"
774         then
775                 printf '%s\n' "pick $shortsha1 $rest" >> "$todo"
776         else
777                 sha1=$(git rev-parse $shortsha1)
778                 if test -z "$rebase_root"
779                 then
780                         preserve=t
781                         for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)
782                         do
783                                 if test -f "$rewritten"/$p
784                                 then
785                                         preserve=f
786                                 fi
787                         done
788                 else
789                         preserve=f
790                 fi
791                 if test f = "$preserve"
792                 then
793                         touch "$rewritten"/$sha1
794                         printf '%s\n' "pick $shortsha1 $rest" >> "$todo"
795                 fi
796         fi
797 done
798
799 # Watch for commits that been dropped by --cherry-pick
800 if test t = "$preserve_merges"
801 then
802         mkdir "$dropped"
803         # Save all non-cherry-picked changes
804         git rev-list $revisions --left-right --cherry-pick | \
805                 sed -n "s/^>//p" > "$state_dir"/not-cherry-picks
806         # Now all commits and note which ones are missing in
807         # not-cherry-picks and hence being dropped
808         git rev-list $revisions |
809         while read rev
810         do
811                 if test -f "$rewritten"/$rev -a "$(sane_grep "$rev" "$state_dir"/not-cherry-picks)" = ""
812                 then
813                         # Use -f2 because if rev-list is telling us this commit is
814                         # not worthwhile, we don't want to track its multiple heads,
815                         # just the history of its first-parent for others that will
816                         # be rebasing on top of it
817                         git rev-list --parents -1 $rev | cut -d' ' -s -f2 > "$dropped"/$rev
818                         short=$(git rev-list -1 --abbrev-commit --abbrev=7 $rev)
819                         sane_grep -v "^[a-z][a-z]* $short" <"$todo" > "${todo}2" ; mv "${todo}2" "$todo"
820                         rm "$rewritten"/$rev
821                 fi
822         done
823 fi
824
825 test -s "$todo" || echo noop >> "$todo"
826 test -n "$autosquash" && rearrange_squash "$todo"
827 cat >> "$todo" << EOF
828
829 # Rebase $shortrevisions onto $shortonto
830 #
831 # Commands:
832 #  p, pick = use commit
833 #  r, reword = use commit, but edit the commit message
834 #  e, edit = use commit, but stop for amending
835 #  s, squash = use commit, but meld into previous commit
836 #  f, fixup = like "squash", but discard this commit's log message
837 #  x, exec = run command (the rest of the line) using shell
838 #
839 # If you remove a line here THAT COMMIT WILL BE LOST.
840 # However, if you remove everything, the rebase will be aborted.
841 #
842 EOF
843
844 has_action "$todo" ||
845         die_abort "Nothing to do"
846
847 cp "$todo" "$todo".backup
848 git_sequence_editor "$todo" ||
849         die_abort "Could not execute editor"
850
851 has_action "$todo" ||
852         die_abort "Nothing to do"
853
854 test -d "$rewritten" || test -n "$force_rebase" || skip_unnecessary_picks
855
856 output git checkout $onto || die_abort "could not detach HEAD"
857 git update-ref ORIG_HEAD $orig_head
858 do_rest