Sync with GIT 1.6.2.5
[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 OPTIONS_KEEPDASHDASH=
14 OPTIONS_SPEC="\
15 git-rebase [-i] [options] [--] <upstream> [<branch>]
16 git-rebase [-i] (--continue | --abort | --skip)
17 --
18  Available options are
19 v,verbose          display a diffstat of what changed upstream
20 onto=              rebase onto given branch instead of upstream
21 p,preserve-merges  try to recreate merges instead of ignoring them
22 s,strategy=        use the given merge strategy
23 m,merge            always used (no-op)
24 i,interactive      always used (no-op)
25  Actions:
26 continue           continue rebasing process
27 abort              abort rebasing process and restore original branch
28 skip               skip current patch and continue rebasing process
29 no-verify          override pre-rebase hook from stopping the operation
30 root               rebase all reachable commmits up to the root(s)
31 "
32
33 . git-sh-setup
34 require_work_tree
35
36 DOTEST="$GIT_DIR/rebase-merge"
37 TODO="$DOTEST"/git-rebase-todo
38 DONE="$DOTEST"/done
39 MSG="$DOTEST"/message
40 SQUASH_MSG="$DOTEST"/message-squash
41 REWRITTEN="$DOTEST"/rewritten
42 DROPPED="$DOTEST"/dropped
43 PRESERVE_MERGES=
44 STRATEGY=
45 ONTO=
46 VERBOSE=
47 OK_TO_SKIP_PRE_REBASE=
48 REBASE_ROOT=
49
50 GIT_CHERRY_PICK_HELP="  After resolving the conflicts,
51 mark the corrected paths with 'git add <paths>', and
52 run 'git rebase --continue'"
53 export GIT_CHERRY_PICK_HELP
54
55 warn () {
56         echo "$*" >&2
57 }
58
59 output () {
60         case "$VERBOSE" in
61         '')
62                 output=$("$@" 2>&1 )
63                 status=$?
64                 test $status != 0 && printf "%s\n" "$output"
65                 return $status
66                 ;;
67         *)
68                 "$@"
69                 ;;
70         esac
71 }
72
73 run_pre_rebase_hook () {
74         if test -z "$OK_TO_SKIP_PRE_REBASE" &&
75            test -x "$GIT_DIR/hooks/pre-rebase"
76         then
77                 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
78                         echo >&2 "The pre-rebase hook refused to rebase."
79                         exit 1
80                 }
81         fi
82 }
83
84 require_clean_work_tree () {
85         # test if working tree is dirty
86         git rev-parse --verify HEAD > /dev/null &&
87         git update-index --ignore-submodules --refresh &&
88         git diff-files --quiet --ignore-submodules &&
89         git diff-index --cached --quiet HEAD --ignore-submodules -- ||
90         die "Working tree is dirty"
91 }
92
93 ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
94
95 comment_for_reflog () {
96         case "$ORIG_REFLOG_ACTION" in
97         ''|rebase*)
98                 GIT_REFLOG_ACTION="rebase -i ($1)"
99                 export GIT_REFLOG_ACTION
100                 ;;
101         esac
102 }
103
104 last_count=
105 mark_action_done () {
106         sed -e 1q < "$TODO" >> "$DONE"
107         sed -e 1d < "$TODO" >> "$TODO".new
108         mv -f "$TODO".new "$TODO"
109         count=$(grep -c '^[^#]' < "$DONE")
110         total=$(($count+$(grep -c '^[^#]' < "$TODO")))
111         if test "$last_count" != "$count"
112         then
113                 last_count=$count
114                 printf "Rebasing (%d/%d)\r" $count $total
115                 test -z "$VERBOSE" || echo
116         fi
117 }
118
119 make_patch () {
120         sha1_and_parents="$(git rev-list --parents -1 "$1")"
121         case "$sha1_and_parents" in
122         ?*' '?*' '?*)
123                 git diff --cc $sha1_and_parents
124                 ;;
125         ?*' '?*)
126                 git diff-tree -p "$1^!"
127                 ;;
128         *)
129                 echo "Root commit"
130                 ;;
131         esac > "$DOTEST"/patch
132         test -f "$DOTEST"/message ||
133                 git cat-file commit "$1" | sed "1,/^$/d" > "$DOTEST"/message
134         test -f "$DOTEST"/author-script ||
135                 get_author_ident_from_commit "$1" > "$DOTEST"/author-script
136 }
137
138 die_with_patch () {
139         make_patch "$1"
140         git rerere
141         die "$2"
142 }
143
144 die_abort () {
145         rm -rf "$DOTEST"
146         die "$1"
147 }
148
149 has_action () {
150         grep '^[^#]' "$1" >/dev/null
151 }
152
153 pick_one () {
154         no_ff=
155         case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
156         output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
157         test -d "$REWRITTEN" &&
158                 pick_one_preserving_merges "$@" && return
159         if test ! -z "$REBASE_ROOT"
160         then
161                 output git cherry-pick "$@"
162                 return
163         fi
164         parent_sha1=$(git rev-parse --verify $sha1^) ||
165                 die "Could not get the parent of $sha1"
166         current_sha1=$(git rev-parse --verify HEAD)
167         if test "$no_ff$current_sha1" = "$parent_sha1"; then
168                 output git reset --hard $sha1
169                 test "a$1" = a-n && output git reset --soft $current_sha1
170                 sha1=$(git rev-parse --short $sha1)
171                 output warn Fast forward to $sha1
172         else
173                 output git cherry-pick "$@"
174         fi
175 }
176
177 pick_one_preserving_merges () {
178         fast_forward=t
179         case "$1" in
180         -n)
181                 fast_forward=f
182                 sha1=$2
183                 ;;
184         *)
185                 sha1=$1
186                 ;;
187         esac
188         sha1=$(git rev-parse $sha1)
189
190         if test -f "$DOTEST"/current-commit
191         then
192                 if test "$fast_forward" = t
193                 then
194                         cat "$DOTEST"/current-commit | while read current_commit
195                         do
196                                 git rev-parse HEAD > "$REWRITTEN"/$current_commit
197                         done
198                         rm "$DOTEST"/current-commit ||
199                         die "Cannot write current commit's replacement sha1"
200                 fi
201         fi
202
203         echo $sha1 >> "$DOTEST"/current-commit
204
205         # rewrite parents; if none were rewritten, we can fast-forward.
206         new_parents=
207         pend=" $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)"
208         if test "$pend" = " "
209         then
210                 pend=" root"
211         fi
212         while [ "$pend" != "" ]
213         do
214                 p=$(expr "$pend" : ' \([^ ]*\)')
215                 pend="${pend# $p}"
216
217                 if test -f "$REWRITTEN"/$p
218                 then
219                         new_p=$(cat "$REWRITTEN"/$p)
220
221                         # If the todo reordered commits, and our parent is marked for
222                         # rewriting, but hasn't been gotten to yet, assume the user meant to
223                         # drop it on top of the current HEAD
224                         if test -z "$new_p"
225                         then
226                                 new_p=$(git rev-parse HEAD)
227                         fi
228
229                         test $p != $new_p && fast_forward=f
230                         case "$new_parents" in
231                         *$new_p*)
232                                 ;; # do nothing; that parent is already there
233                         *)
234                                 new_parents="$new_parents $new_p"
235                                 ;;
236                         esac
237                 else
238                         if test -f "$DROPPED"/$p
239                         then
240                                 fast_forward=f
241                                 replacement="$(cat "$DROPPED"/$p)"
242                                 test -z "$replacement" && replacement=root
243                                 pend=" $replacement$pend"
244                         else
245                                 new_parents="$new_parents $p"
246                         fi
247                 fi
248         done
249         case $fast_forward in
250         t)
251                 output warn "Fast forward to $sha1"
252                 output git reset --hard $sha1 ||
253                         die "Cannot fast forward to $sha1"
254                 ;;
255         f)
256                 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
257
258                 if [ "$1" != "-n" ]
259                 then
260                         # detach HEAD to current parent
261                         output git checkout $first_parent 2> /dev/null ||
262                                 die "Cannot move HEAD to $first_parent"
263                 fi
264
265                 case "$new_parents" in
266                 ' '*' '*)
267                         test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
268
269                         # redo merge
270                         author_script=$(get_author_ident_from_commit $sha1)
271                         eval "$author_script"
272                         msg="$(git cat-file commit $sha1 | sed -e '1,/^$/d')"
273                         # No point in merging the first parent, that's HEAD
274                         new_parents=${new_parents# $first_parent}
275                         if ! GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
276                                 GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
277                                 GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
278                                 output git merge $STRATEGY -m "$msg" \
279                                         $new_parents
280                         then
281                                 printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
282                                 die_with_patch $sha1 "Error redoing merge $sha1"
283                         fi
284                         ;;
285                 *)
286                         output git cherry-pick "$@" ||
287                                 die_with_patch $sha1 "Could not pick $sha1"
288                         ;;
289                 esac
290                 ;;
291         esac
292 }
293
294 nth_string () {
295         case "$1" in
296         *1[0-9]|*[04-9]) echo "$1"th;;
297         *1) echo "$1"st;;
298         *2) echo "$1"nd;;
299         *3) echo "$1"rd;;
300         esac
301 }
302
303 make_squash_message () {
304         if test -f "$SQUASH_MSG"; then
305                 COUNT=$(($(sed -n "s/^# This is [^0-9]*\([1-9][0-9]*\).*/\1/p" \
306                         < "$SQUASH_MSG" | sed -ne '$p')+1))
307                 echo "# This is a combination of $COUNT commits."
308                 sed -e 1d -e '2,/^./{
309                         /^$/d
310                 }' <"$SQUASH_MSG"
311         else
312                 COUNT=2
313                 echo "# This is a combination of two commits."
314                 echo "# The first commit's message is:"
315                 echo
316                 git cat-file commit HEAD | sed -e '1,/^$/d'
317         fi
318         echo
319         echo "# This is the $(nth_string $COUNT) commit message:"
320         echo
321         git cat-file commit $1 | sed -e '1,/^$/d'
322 }
323
324 peek_next_command () {
325         sed -n "1s/ .*$//p" < "$TODO"
326 }
327
328 do_next () {
329         rm -f "$DOTEST"/message "$DOTEST"/author-script \
330                 "$DOTEST"/amend || exit
331         read command sha1 rest < "$TODO"
332         case "$command" in
333         '#'*|''|noop)
334                 mark_action_done
335                 ;;
336         pick|p)
337                 comment_for_reflog pick
338
339                 mark_action_done
340                 pick_one $sha1 ||
341                         die_with_patch $sha1 "Could not apply $sha1... $rest"
342                 ;;
343         edit|e)
344                 comment_for_reflog edit
345
346                 mark_action_done
347                 pick_one $sha1 ||
348                         die_with_patch $sha1 "Could not apply $sha1... $rest"
349                 make_patch $sha1
350                 git rev-parse --verify HEAD > "$DOTEST"/amend
351                 warn "Stopped at $sha1... $rest"
352                 warn "You can amend the commit now, with"
353                 warn
354                 warn "  git commit --amend"
355                 warn
356                 warn "Once you are satisfied with your changes, run"
357                 warn
358                 warn "  git rebase --continue"
359                 warn
360                 exit 0
361                 ;;
362         squash|s)
363                 comment_for_reflog squash
364
365                 test -f "$DONE" && has_action "$DONE" ||
366                         die "Cannot 'squash' without a previous commit"
367
368                 mark_action_done
369                 make_squash_message $sha1 > "$MSG"
370                 failed=f
371                 author_script=$(get_author_ident_from_commit HEAD)
372                 output git reset --soft HEAD^
373                 pick_one -n $sha1 || failed=t
374                 case "$(peek_next_command)" in
375                 squash|s)
376                         USE_OUTPUT=output
377                         MSG_OPT=-F
378                         EDIT_OR_FILE="$MSG"
379                         cp "$MSG" "$SQUASH_MSG"
380                         ;;
381                 *)
382                         USE_OUTPUT=
383                         MSG_OPT=
384                         EDIT_OR_FILE=-e
385                         rm -f "$SQUASH_MSG" || exit
386                         cp "$MSG" "$GIT_DIR"/SQUASH_MSG
387                         rm -f "$GIT_DIR"/MERGE_MSG || exit
388                         ;;
389                 esac
390                 echo "$author_script" > "$DOTEST"/author-script
391                 if test $failed = f
392                 then
393                         # This is like --amend, but with a different message
394                         eval "$author_script"
395                         GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
396                         GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
397                         GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
398                         $USE_OUTPUT git commit --no-verify \
399                                 $MSG_OPT "$EDIT_OR_FILE" || failed=t
400                 fi
401                 if test $failed = t
402                 then
403                         cp "$MSG" "$GIT_DIR"/MERGE_MSG
404                         warn
405                         warn "Could not apply $sha1... $rest"
406                         die_with_patch $sha1 ""
407                 fi
408                 ;;
409         *)
410                 warn "Unknown command: $command $sha1 $rest"
411                 die_with_patch $sha1 "Please fix this in the file $TODO."
412                 ;;
413         esac
414         test -s "$TODO" && return
415
416         comment_for_reflog finish &&
417         HEADNAME=$(cat "$DOTEST"/head-name) &&
418         OLDHEAD=$(cat "$DOTEST"/head) &&
419         SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
420         NEWHEAD=$(git rev-parse HEAD) &&
421         case $HEADNAME in
422         refs/*)
423                 message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
424                 git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
425                 git symbolic-ref HEAD $HEADNAME
426                 ;;
427         esac && {
428                 test ! -f "$DOTEST"/verbose ||
429                         git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
430         } &&
431         rm -rf "$DOTEST" &&
432         git gc --auto &&
433         warn "Successfully rebased and updated $HEADNAME."
434
435         exit
436 }
437
438 do_rest () {
439         while :
440         do
441                 do_next
442         done
443 }
444
445 # skip picking commits whose parents are unchanged
446 skip_unnecessary_picks () {
447         fd=3
448         while read command sha1 rest
449         do
450                 # fd=3 means we skip the command
451                 case "$fd,$command,$(git rev-parse --verify --quiet $sha1^)" in
452                 3,pick,"$ONTO"*|3,p,"$ONTO"*)
453                         # pick a commit whose parent is current $ONTO -> skip
454                         ONTO=$sha1
455                         ;;
456                 3,#*|3,,*)
457                         # copy comments
458                         ;;
459                 *)
460                         fd=1
461                         ;;
462                 esac
463                 echo "$command${sha1:+ }$sha1${rest:+ }$rest" >&$fd
464         done <"$TODO" >"$TODO.new" 3>>"$DONE" &&
465         mv -f "$TODO".new "$TODO" ||
466         die "Could not skip unnecessary pick commands"
467 }
468
469 # check if no other options are set
470 is_standalone () {
471         test $# -eq 2 -a "$2" = '--' &&
472         test -z "$ONTO" &&
473         test -z "$PRESERVE_MERGES" &&
474         test -z "$STRATEGY" &&
475         test -z "$VERBOSE"
476 }
477
478 get_saved_options () {
479         test -d "$REWRITTEN" && PRESERVE_MERGES=t
480         test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
481         test -f "$DOTEST"/verbose && VERBOSE=t
482         test -f "$DOTEST"/rebase-root && REBASE_ROOT=t
483 }
484
485 while test $# != 0
486 do
487         case "$1" in
488         --no-verify)
489                 OK_TO_SKIP_PRE_REBASE=yes
490                 ;;
491         --verify)
492                 ;;
493         --continue)
494                 is_standalone "$@" || usage
495                 get_saved_options
496                 comment_for_reflog continue
497
498                 test -d "$DOTEST" || die "No interactive rebase running"
499
500                 # Sanity check
501                 git rev-parse --verify HEAD >/dev/null ||
502                         die "Cannot read HEAD"
503                 git update-index --ignore-submodules --refresh &&
504                         git diff-files --quiet --ignore-submodules ||
505                         die "Working tree is dirty"
506
507                 # do we have anything to commit?
508                 if git diff-index --cached --quiet --ignore-submodules HEAD --
509                 then
510                         : Nothing to commit -- skip this
511                 else
512                         . "$DOTEST"/author-script ||
513                                 die "Cannot find the author identity"
514                         amend=
515                         if test -f "$DOTEST"/amend
516                         then
517                                 amend=$(git rev-parse --verify HEAD)
518                                 test "$amend" = $(cat "$DOTEST"/amend) ||
519                                 die "\
520 You have uncommitted changes in your working tree. Please, commit them
521 first and then run 'git rebase --continue' again."
522                                 git reset --soft HEAD^ ||
523                                 die "Cannot rewind the HEAD"
524                         fi
525                         export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE &&
526                         git commit --no-verify -F "$DOTEST"/message -e || {
527                                 test -n "$amend" && git reset --soft $amend
528                                 die "Could not commit staged changes."
529                         }
530                 fi
531
532                 require_clean_work_tree
533                 do_rest
534                 ;;
535         --abort)
536                 is_standalone "$@" || usage
537                 get_saved_options
538                 comment_for_reflog abort
539
540                 git rerere clear
541                 test -d "$DOTEST" || die "No interactive rebase running"
542
543                 HEADNAME=$(cat "$DOTEST"/head-name)
544                 HEAD=$(cat "$DOTEST"/head)
545                 case $HEADNAME in
546                 refs/*)
547                         git symbolic-ref HEAD $HEADNAME
548                         ;;
549                 esac &&
550                 output git reset --hard $HEAD &&
551                 rm -rf "$DOTEST"
552                 exit
553                 ;;
554         --skip)
555                 is_standalone "$@" || usage
556                 get_saved_options
557                 comment_for_reflog skip
558
559                 git rerere clear
560                 test -d "$DOTEST" || die "No interactive rebase running"
561
562                 output git reset --hard && do_rest
563                 ;;
564         -s)
565                 case "$#,$1" in
566                 *,*=*)
567                         STRATEGY="-s "$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
568                 1,*)
569                         usage ;;
570                 *)
571                         STRATEGY="-s $2"
572                         shift ;;
573                 esac
574                 ;;
575         -m)
576                 # we use merge anyway
577                 ;;
578         -v)
579                 VERBOSE=t
580                 ;;
581         -p)
582                 PRESERVE_MERGES=t
583                 ;;
584         -i)
585                 # yeah, we know
586                 ;;
587         --root)
588                 REBASE_ROOT=t
589                 ;;
590         --onto)
591                 shift
592                 ONTO=$(git rev-parse --verify "$1") ||
593                         die "Does not point to a valid commit: $1"
594                 ;;
595         --)
596                 shift
597                 test -z "$REBASE_ROOT" -a $# -ge 1 -a $# -le 2 ||
598                 test ! -z "$REBASE_ROOT" -a $# -le 1 || usage
599                 test -d "$DOTEST" &&
600                         die "Interactive rebase already started"
601
602                 git var GIT_COMMITTER_IDENT >/dev/null ||
603                         die "You need to set your committer info first"
604
605                 if test -z "$REBASE_ROOT"
606                 then
607                         UPSTREAM_ARG="$1"
608                         UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
609                         test -z "$ONTO" && ONTO=$UPSTREAM
610                         shift
611                 else
612                         UPSTREAM=
613                         UPSTREAM_ARG=--root
614                         test -z "$ONTO" &&
615                                 die "You must specify --onto when using --root"
616                 fi
617                 run_pre_rebase_hook "$UPSTREAM_ARG" "$@"
618
619                 comment_for_reflog start
620
621                 require_clean_work_tree
622
623                 if test ! -z "$1"
624                 then
625                         output git show-ref --verify --quiet "refs/heads/$1" ||
626                                 die "Invalid branchname: $1"
627                         output git checkout "$1" ||
628                                 die "Could not checkout $1"
629                 fi
630
631                 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
632                 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
633
634                 : > "$DOTEST"/interactive || die "Could not mark as interactive"
635                 git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
636                         echo "detached HEAD" > "$DOTEST"/head-name
637
638                 echo $HEAD > "$DOTEST"/head
639                 case "$REBASE_ROOT" in
640                 '')
641                         rm -f "$DOTEST"/rebase-root ;;
642                 *)
643                         : >"$DOTEST"/rebase-root ;;
644                 esac
645                 echo $ONTO > "$DOTEST"/onto
646                 test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
647                 test t = "$VERBOSE" && : > "$DOTEST"/verbose
648                 if test t = "$PRESERVE_MERGES"
649                 then
650                         # $REWRITTEN contains files for each commit that is
651                         # reachable by at least one merge base of $HEAD and
652                         # $UPSTREAM. They are not necessarily rewritten, but
653                         # their children might be.
654                         # This ensures that commits on merged, but otherwise
655                         # unrelated side branches are left alone. (Think "X"
656                         # in the man page's example.)
657                         if test -z "$REBASE_ROOT"
658                         then
659                                 mkdir "$REWRITTEN" &&
660                                 for c in $(git merge-base --all $HEAD $UPSTREAM)
661                                 do
662                                         echo $ONTO > "$REWRITTEN"/$c ||
663                                                 die "Could not init rewritten commits"
664                                 done
665                         else
666                                 mkdir "$REWRITTEN" &&
667                                 echo $ONTO > "$REWRITTEN"/root ||
668                                         die "Could not init rewritten commits"
669                         fi
670                         # No cherry-pick because our first pass is to determine
671                         # parents to rewrite and skipping dropped commits would
672                         # prematurely end our probe
673                         MERGES_OPTION=
674                         first_after_upstream="$(git rev-list --reverse --first-parent $UPSTREAM..$HEAD | head -n 1)"
675                 else
676                         MERGES_OPTION="--no-merges --cherry-pick"
677                 fi
678
679                 SHORTHEAD=$(git rev-parse --short $HEAD)
680                 SHORTONTO=$(git rev-parse --short $ONTO)
681                 if test -z "$REBASE_ROOT"
682                         # this is now equivalent to ! -z "$UPSTREAM"
683                 then
684                         SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
685                         REVISIONS=$UPSTREAM...$HEAD
686                         SHORTREVISIONS=$SHORTUPSTREAM..$SHORTHEAD
687                 else
688                         REVISIONS=$ONTO...$HEAD
689                         SHORTREVISIONS=$SHORTHEAD
690                 fi
691                 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
692                         --abbrev=7 --reverse --left-right --topo-order \
693                         $REVISIONS | \
694                         sed -n "s/^>//p" | while read shortsha1 rest
695                 do
696                         if test t != "$PRESERVE_MERGES"
697                         then
698                                 echo "pick $shortsha1 $rest" >> "$TODO"
699                         else
700                                 sha1=$(git rev-parse $shortsha1)
701                                 if test -z "$REBASE_ROOT"
702                                 then
703                                         preserve=t
704                                         for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)
705                                         do
706                                                 if test -f "$REWRITTEN"/$p -a \( $p != $UPSTREAM -o $sha1 = $first_after_upstream \)
707                                                 then
708                                                         preserve=f
709                                                 fi
710                                         done
711                                 else
712                                         preserve=f
713                                 fi
714                                 if test f = "$preserve"
715                                 then
716                                         touch "$REWRITTEN"/$sha1
717                                         echo "pick $shortsha1 $rest" >> "$TODO"
718                                 fi
719                         fi
720                 done
721
722                 # Watch for commits that been dropped by --cherry-pick
723                 if test t = "$PRESERVE_MERGES"
724                 then
725                         mkdir "$DROPPED"
726                         # Save all non-cherry-picked changes
727                         git rev-list $REVISIONS --left-right --cherry-pick | \
728                                 sed -n "s/^>//p" > "$DOTEST"/not-cherry-picks
729                         # Now all commits and note which ones are missing in
730                         # not-cherry-picks and hence being dropped
731                         git rev-list $REVISIONS |
732                         while read rev
733                         do
734                                 if test -f "$REWRITTEN"/$rev -a "$(grep "$rev" "$DOTEST"/not-cherry-picks)" = ""
735                                 then
736                                         # Use -f2 because if rev-list is telling us this commit is
737                                         # not worthwhile, we don't want to track its multiple heads,
738                                         # just the history of its first-parent for others that will
739                                         # be rebasing on top of it
740                                         git rev-list --parents -1 $rev | cut -d' ' -s -f2 > "$DROPPED"/$rev
741                                         short=$(git rev-list -1 --abbrev-commit --abbrev=7 $rev)
742                                         grep -v "^[a-z][a-z]* $short" <"$TODO" > "${TODO}2" ; mv "${TODO}2" "$TODO"
743                                         rm "$REWRITTEN"/$rev
744                                 fi
745                         done
746                 fi
747
748                 test -s "$TODO" || echo noop >> "$TODO"
749                 cat >> "$TODO" << EOF
750
751 # Rebase $SHORTREVISIONS onto $SHORTONTO
752 #
753 # Commands:
754 #  p, pick = use commit
755 #  e, edit = use commit, but stop for amending
756 #  s, squash = use commit, but meld into previous commit
757 #
758 # If you remove a line here THAT COMMIT WILL BE LOST.
759 # However, if you remove everything, the rebase will be aborted.
760 #
761 EOF
762
763                 has_action "$TODO" ||
764                         die_abort "Nothing to do"
765
766                 cp "$TODO" "$TODO".backup
767                 git_editor "$TODO" ||
768                         die "Could not execute editor"
769
770                 has_action "$TODO" ||
771                         die_abort "Nothing to do"
772
773                 test -d "$REWRITTEN" || skip_unnecessary_picks
774
775                 git update-ref ORIG_HEAD $HEAD
776                 output git checkout $ONTO && do_rest
777                 ;;
778         esac
779         shift
780 done