bisect--helper: `bisect_start` shell function partially in C
[git] / git-legacy-rebase.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano.
4 #
5
6 SUBDIRECTORY_OK=Yes
7 OPTIONS_KEEPDASHDASH=
8 OPTIONS_STUCKLONG=t
9 OPTIONS_SPEC="\
10 git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] [<upstream>] [<branch>]
11 git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] --root [<branch>]
12 git rebase --continue | --abort | --skip | --edit-todo
13 --
14  Available options are
15 v,verbose!         display a diffstat of what changed upstream
16 q,quiet!           be quiet. implies --no-stat
17 autostash          automatically stash/stash pop before and after
18 fork-point         use 'merge-base --fork-point' to refine upstream
19 onto=!             rebase onto given branch instead of upstream
20 r,rebase-merges?   try to rebase merges instead of skipping them
21 p,preserve-merges! try to recreate merges instead of ignoring them
22 s,strategy=!       use the given merge strategy
23 X,strategy-option=! pass the argument through to the merge strategy
24 no-ff!             cherry-pick all commits, even if unchanged
25 f,force-rebase!    cherry-pick all commits, even if unchanged
26 m,merge!           use merging strategies to rebase
27 i,interactive!     let the user edit the list of commits to rebase
28 x,exec=!           add exec lines after each commit of the editable list
29 k,keep-empty       preserve empty commits during rebase
30 allow-empty-message allow rebasing commits with empty messages
31 stat!              display a diffstat of what changed upstream
32 n,no-stat!         do not show diffstat of what changed upstream
33 verify             allow pre-rebase hook to run
34 rerere-autoupdate  allow rerere to update index with resolved conflicts
35 root!              rebase all reachable commits up to the root(s)
36 autosquash         move commits that begin with squash!/fixup! under -i
37 signoff            add a Signed-off-by: line to each commit
38 committer-date-is-author-date! passed to 'git am'
39 ignore-date!       passed to 'git am'
40 whitespace=!       passed to 'git apply'
41 ignore-whitespace! passed to 'git apply'
42 C=!                passed to 'git apply'
43 S,gpg-sign?        GPG-sign commits
44  Actions:
45 continue!          continue
46 abort!             abort and check out the original branch
47 skip!              skip current patch and continue
48 edit-todo!         edit the todo list during an interactive rebase
49 quit!              abort but keep HEAD where it is
50 show-current-patch! show the patch file being applied or merged
51 "
52 . git-sh-setup
53 set_reflog_action rebase
54 require_work_tree_exists
55 cd_to_toplevel
56
57 LF='
58 '
59 ok_to_skip_pre_rebase=
60
61 squash_onto=
62 unset onto
63 unset restrict_revision
64 cmd=
65 strategy=
66 strategy_opts=
67 do_merge=
68 merge_dir="$GIT_DIR"/rebase-merge
69 apply_dir="$GIT_DIR"/rebase-apply
70 verbose=
71 diffstat=
72 test "$(git config --bool rebase.stat)" = true && diffstat=t
73 autostash="$(git config --bool rebase.autostash || echo false)"
74 fork_point=auto
75 git_am_opt=
76 git_format_patch_opt=
77 rebase_root=
78 force_rebase=
79 allow_rerere_autoupdate=
80 # Non-empty if a rebase was in progress when 'git rebase' was invoked
81 in_progress=
82 # One of {am, merge, interactive}
83 type=
84 # One of {"$GIT_DIR"/rebase-apply, "$GIT_DIR"/rebase-merge}
85 state_dir=
86 # One of {'', continue, skip, abort}, as parsed from command line
87 action=
88 rebase_merges=
89 rebase_cousins=
90 preserve_merges=
91 autosquash=
92 keep_empty=
93 allow_empty_message=--allow-empty-message
94 signoff=
95 test "$(git config --bool rebase.autosquash)" = "true" && autosquash=t
96 case "$(git config --bool commit.gpgsign)" in
97 true)   gpg_sign_opt=-S ;;
98 *)      gpg_sign_opt= ;;
99 esac
100 . git-rebase--common
101
102 read_basic_state () {
103         test -f "$state_dir/head-name" &&
104         test -f "$state_dir/onto" &&
105         head_name=$(cat "$state_dir"/head-name) &&
106         onto=$(cat "$state_dir"/onto) &&
107         # We always write to orig-head, but interactive rebase used to write to
108         # head. Fall back to reading from head to cover for the case that the
109         # user upgraded git with an ongoing interactive rebase.
110         if test -f "$state_dir"/orig-head
111         then
112                 orig_head=$(cat "$state_dir"/orig-head)
113         else
114                 orig_head=$(cat "$state_dir"/head)
115         fi &&
116         GIT_QUIET=$(cat "$state_dir"/quiet) &&
117         test -f "$state_dir"/verbose && verbose=t
118         test -f "$state_dir"/strategy && strategy="$(cat "$state_dir"/strategy)"
119         test -f "$state_dir"/strategy_opts &&
120                 strategy_opts="$(cat "$state_dir"/strategy_opts)"
121         test -f "$state_dir"/allow_rerere_autoupdate &&
122                 allow_rerere_autoupdate="$(cat "$state_dir"/allow_rerere_autoupdate)"
123         test -f "$state_dir"/gpg_sign_opt &&
124                 gpg_sign_opt="$(cat "$state_dir"/gpg_sign_opt)"
125         test -f "$state_dir"/signoff && {
126                 signoff="$(cat "$state_dir"/signoff)"
127                 force_rebase=t
128         }
129 }
130
131 finish_rebase () {
132         rm -f "$(git rev-parse --git-path REBASE_HEAD)"
133         apply_autostash &&
134         { git gc --auto || true; } &&
135         rm -rf "$state_dir"
136 }
137
138 run_interactive () {
139         GIT_CHERRY_PICK_HELP="$resolvemsg"
140         export GIT_CHERRY_PICK_HELP
141
142         test -n "$keep_empty" && keep_empty="--keep-empty"
143         test -n "$rebase_merges" && rebase_merges="--rebase-merges"
144         test -n "$rebase_cousins" && rebase_cousins="--rebase-cousins"
145         test -n "$autosquash" && autosquash="--autosquash"
146         test -n "$verbose" && verbose="--verbose"
147         test -n "$force_rebase" && force_rebase="--no-ff"
148         test -n "$restrict_revision" && \
149                 restrict_revision="--restrict-revision=^$restrict_revision"
150         test -n "$upstream" && upstream="--upstream=$upstream"
151         test -n "$onto" && onto="--onto=$onto"
152         test -n "$squash_onto" && squash_onto="--squash-onto=$squash_onto"
153         test -n "$onto_name" && onto_name="--onto-name=$onto_name"
154         test -n "$head_name" && head_name="--head-name=$head_name"
155         test -n "$strategy" && strategy="--strategy=$strategy"
156         test -n "$strategy_opts" && strategy_opts="--strategy-opts=$strategy_opts"
157         test -n "$switch_to" && switch_to="--switch-to=$switch_to"
158         test -n "$cmd" && cmd="--cmd=$cmd"
159         test -n "$action" && action="--$action"
160
161         exec git rebase--interactive "$action" "$keep_empty" "$rebase_merges" "$rebase_cousins" \
162                 "$upstream" "$onto" "$squash_onto" "$restrict_revision" \
163                 "$allow_empty_message" "$autosquash" "$verbose" \
164                 "$force_rebase" "$onto_name" "$head_name" "$strategy" \
165                 "$strategy_opts" "$cmd" "$switch_to" \
166                 "$allow_rerere_autoupdate" "$gpg_sign_opt" "$signoff"
167 }
168
169 run_specific_rebase () {
170         if [ "$interactive_rebase" = implied ]; then
171                 GIT_EDITOR=:
172                 export GIT_EDITOR
173                 autosquash=
174         fi
175
176         if test -n "$interactive_rebase" -a -z "$preserve_merges"
177         then
178                 run_interactive
179         else
180                 . git-rebase--$type
181
182                 if test -z "$preserve_merges"
183                 then
184                         git_rebase__$type
185                 else
186                         git_rebase__preserve_merges
187                 fi
188         fi
189
190         ret=$?
191         if test $ret -eq 0
192         then
193                 finish_rebase
194         elif test $ret -eq 2 # special exit status for rebase -p
195         then
196                 apply_autostash &&
197                 rm -rf "$state_dir" &&
198                 die "Nothing to do"
199         fi
200         exit $ret
201 }
202
203 run_pre_rebase_hook () {
204         if test -z "$ok_to_skip_pre_rebase" &&
205            test -x "$(git rev-parse --git-path hooks/pre-rebase)"
206         then
207                 "$(git rev-parse --git-path hooks/pre-rebase)" ${1+"$@"} ||
208                 die "$(gettext "The pre-rebase hook refused to rebase.")"
209         fi
210 }
211
212 test -f "$apply_dir"/applying &&
213         die "$(gettext "It looks like 'git am' is in progress. Cannot rebase.")"
214
215 if test -d "$apply_dir"
216 then
217         type=am
218         state_dir="$apply_dir"
219 elif test -d "$merge_dir"
220 then
221         if test -d "$merge_dir"/rewritten
222         then
223                 type=preserve-merges
224                 interactive_rebase=explicit
225                 preserve_merges=t
226         elif test -f "$merge_dir"/interactive
227         then
228                 type=interactive
229                 interactive_rebase=explicit
230         else
231                 type=merge
232         fi
233         state_dir="$merge_dir"
234 fi
235 test -n "$type" && in_progress=t
236
237 total_argc=$#
238 while test $# != 0
239 do
240         case "$1" in
241         --no-verify)
242                 ok_to_skip_pre_rebase=yes
243                 ;;
244         --verify)
245                 ok_to_skip_pre_rebase=
246                 ;;
247         --continue|--skip|--abort|--quit|--edit-todo|--show-current-patch)
248                 test $total_argc -eq 2 || usage
249                 action=${1##--}
250                 ;;
251         --onto=*)
252                 onto="${1#--onto=}"
253                 ;;
254         --exec=*)
255                 cmd="${cmd}exec ${1#--exec=}${LF}"
256                 test -z "$interactive_rebase" && interactive_rebase=implied
257                 ;;
258         --interactive)
259                 interactive_rebase=explicit
260                 ;;
261         --keep-empty)
262                 keep_empty=yes
263                 ;;
264         --allow-empty-message)
265                 allow_empty_message=--allow-empty-message
266                 ;;
267         --no-keep-empty)
268                 keep_empty=
269                 ;;
270         --rebase-merges)
271                 rebase_merges=t
272                 test -z "$interactive_rebase" && interactive_rebase=implied
273                 ;;
274         --rebase-merges=*)
275                 rebase_merges=t
276                 case "${1#*=}" in
277                 rebase-cousins) rebase_cousins=t;;
278                 no-rebase-cousins) rebase_cousins=;;
279                 *) die "Unknown mode: $1";;
280                 esac
281                 test -z "$interactive_rebase" && interactive_rebase=implied
282                 ;;
283         --preserve-merges)
284                 preserve_merges=t
285                 test -z "$interactive_rebase" && interactive_rebase=implied
286                 ;;
287         --autosquash)
288                 autosquash=t
289                 ;;
290         --no-autosquash)
291                 autosquash=
292                 ;;
293         --fork-point)
294                 fork_point=t
295                 ;;
296         --no-fork-point)
297                 fork_point=
298                 ;;
299         --merge)
300                 do_merge=t
301                 ;;
302         --strategy-option=*)
303                 strategy_opts="$strategy_opts $(git rev-parse --sq-quote "--${1#--strategy-option=}" | sed -e s/^.//)"
304                 do_merge=t
305                 test -z "$strategy" && strategy=recursive
306                 ;;
307         --strategy=*)
308                 strategy="${1#--strategy=}"
309                 do_merge=t
310                 ;;
311         --no-stat)
312                 diffstat=
313                 ;;
314         --stat)
315                 diffstat=t
316                 ;;
317         --autostash)
318                 autostash=true
319                 ;;
320         --no-autostash)
321                 autostash=false
322                 ;;
323         --verbose)
324                 verbose=t
325                 diffstat=t
326                 GIT_QUIET=
327                 ;;
328         --quiet)
329                 GIT_QUIET=t
330                 git_am_opt="$git_am_opt -q"
331                 verbose=
332                 diffstat=
333                 ;;
334         --whitespace=*)
335                 git_am_opt="$git_am_opt --whitespace=${1#--whitespace=}"
336                 case "${1#--whitespace=}" in
337                 fix|strip)
338                         force_rebase=t
339                         ;;
340                 warn|nowarn|error|error-all)
341                         ;; # okay, known whitespace option
342                 *)
343                         die "fatal: Invalid whitespace option: '${1#*=}'"
344                         ;;
345                 esac
346                 ;;
347         --ignore-whitespace)
348                 git_am_opt="$git_am_opt $1"
349                 ;;
350         --signoff)
351                 signoff=--signoff
352                 ;;
353         --no-signoff)
354                 signoff=
355                 ;;
356         --committer-date-is-author-date|--ignore-date)
357                 git_am_opt="$git_am_opt $1"
358                 force_rebase=t
359                 ;;
360         -C*[!0-9]*)
361                 die "fatal: switch \`C' expects a numerical value"
362                 ;;
363         -C*)
364                 git_am_opt="$git_am_opt $1"
365                 ;;
366         --root)
367                 rebase_root=t
368                 ;;
369         --force-rebase|--no-ff)
370                 force_rebase=t
371                 ;;
372         --rerere-autoupdate|--no-rerere-autoupdate)
373                 allow_rerere_autoupdate="$1"
374                 ;;
375         --gpg-sign)
376                 gpg_sign_opt=-S
377                 ;;
378         --gpg-sign=*)
379                 gpg_sign_opt="-S${1#--gpg-sign=}"
380                 ;;
381         --)
382                 shift
383                 break
384                 ;;
385         *)
386                 usage
387                 ;;
388         esac
389         shift
390 done
391 test $# -gt 2 && usage
392
393 if test -n "$action"
394 then
395         test -z "$in_progress" && die "$(gettext "No rebase in progress?")"
396         # Only interactive rebase uses detailed reflog messages
397         if test -n "$interactive_rebase" && test "$GIT_REFLOG_ACTION" = rebase
398         then
399                 GIT_REFLOG_ACTION="rebase -i ($action)"
400                 export GIT_REFLOG_ACTION
401         fi
402 fi
403
404 if test "$action" = "edit-todo" && test -z "$interactive_rebase"
405 then
406         die "$(gettext "The --edit-todo action can only be used during interactive rebase.")"
407 fi
408
409 case "$action" in
410 continue)
411         # Sanity check
412         git rev-parse --verify HEAD >/dev/null ||
413                 die "$(gettext "Cannot read HEAD")"
414         git update-index --ignore-submodules --refresh &&
415         git diff-files --quiet --ignore-submodules || {
416                 echo "$(gettext "You must edit all merge conflicts and then
417 mark them as resolved using git add")"
418                 exit 1
419         }
420         read_basic_state
421         run_specific_rebase
422         ;;
423 skip)
424         output git reset --hard HEAD || exit $?
425         read_basic_state
426         run_specific_rebase
427         ;;
428 abort)
429         git rerere clear
430         read_basic_state
431         case "$head_name" in
432         refs/*)
433                 git symbolic-ref -m "rebase: aborting" HEAD $head_name ||
434                 die "$(eval_gettext "Could not move back to \$head_name")"
435                 ;;
436         esac
437         output git reset --hard $orig_head
438         finish_rebase
439         exit
440         ;;
441 quit)
442         exec rm -rf "$state_dir"
443         ;;
444 edit-todo)
445         run_specific_rebase
446         ;;
447 show-current-patch)
448         run_specific_rebase
449         die "BUG: run_specific_rebase is not supposed to return here"
450         ;;
451 esac
452
453 # Make sure no rebase is in progress
454 if test -n "$in_progress"
455 then
456         state_dir_base=${state_dir##*/}
457         cmd_live_rebase="git rebase (--continue | --abort | --skip)"
458         cmd_clear_stale_rebase="rm -fr \"$state_dir\""
459         die "
460 $(eval_gettext 'It seems that there is already a $state_dir_base directory, and
461 I wonder if you are in the middle of another rebase.  If that is the
462 case, please try
463         $cmd_live_rebase
464 If that is not the case, please
465         $cmd_clear_stale_rebase
466 and run me again.  I am stopping in case you still have something
467 valuable there.')"
468 fi
469
470 if test -n "$rebase_root" && test -z "$onto"
471 then
472         test -z "$interactive_rebase" && interactive_rebase=implied
473 fi
474
475 if test -n "$keep_empty"
476 then
477         test -z "$interactive_rebase" && interactive_rebase=implied
478 fi
479
480 if test -n "$interactive_rebase"
481 then
482         if test -z "$preserve_merges"
483         then
484                 type=interactive
485         else
486                 type=preserve-merges
487         fi
488
489         state_dir="$merge_dir"
490 elif test -n "$do_merge"
491 then
492         type=merge
493         state_dir="$merge_dir"
494 else
495         type=am
496         state_dir="$apply_dir"
497 fi
498
499 if test -t 2 && test -z "$GIT_QUIET"
500 then
501         git_format_patch_opt="$git_format_patch_opt --progress"
502 fi
503
504 if test -n "$git_am_opt"; then
505         incompatible_opts=$(echo " $git_am_opt " | \
506                             sed -e 's/ -q / /g' -e 's/^ \(.*\) $/\1/')
507         if test -n "$interactive_rebase"
508         then
509                 if test -n "$incompatible_opts"
510                 then
511                         die "$(gettext "error: cannot combine interactive options (--interactive, --exec, --rebase-merges, --preserve-merges, --keep-empty, --root + --onto) with am options ($incompatible_opts)")"
512                 fi
513         fi
514         if test -n "$do_merge"; then
515                 if test -n "$incompatible_opts"
516                 then
517                         die "$(gettext "error: cannot combine merge options (--merge, --strategy, --strategy-option) with am options ($incompatible_opts)")"
518                 fi
519         fi
520 fi
521
522 if test -n "$signoff"
523 then
524         test -n "$preserve_merges" &&
525                 die "$(gettext "error: cannot combine '--signoff' with '--preserve-merges'")"
526         git_am_opt="$git_am_opt $signoff"
527         force_rebase=t
528 fi
529
530 if test -n "$preserve_merges"
531 then
532         # Note: incompatibility with --signoff handled in signoff block above
533         # Note: incompatibility with --interactive is just a strong warning;
534         #       git-rebase.txt caveats with "unless you know what you are doing"
535         test -n "$rebase_merges" &&
536                 die "$(gettext "error: cannot combine '--preserve-merges' with '--rebase-merges'")"
537 fi
538
539 if test -n "$rebase_merges"
540 then
541         test -n "$strategy_opts" &&
542                 die "$(gettext "error: cannot combine '--rebase-merges' with '--strategy-option'")"
543         test -n "$strategy" &&
544                 die "$(gettext "error: cannot combine '--rebase-merges' with '--strategy'")"
545 fi
546
547 if test -z "$rebase_root"
548 then
549         case "$#" in
550         0)
551                 if ! upstream_name=$(git rev-parse --symbolic-full-name \
552                         --verify -q @{upstream} 2>/dev/null)
553                 then
554                         . git-parse-remote
555                         error_on_missing_default_upstream "rebase" "rebase" \
556                                 "against" "git rebase $(gettext '<branch>')"
557                 fi
558
559                 test "$fork_point" = auto && fork_point=t
560                 ;;
561         *)      upstream_name="$1"
562                 if test "$upstream_name" = "-"
563                 then
564                         upstream_name="@{-1}"
565                 fi
566                 shift
567                 ;;
568         esac
569         upstream=$(peel_committish "${upstream_name}") ||
570         die "$(eval_gettext "invalid upstream '\$upstream_name'")"
571         upstream_arg="$upstream_name"
572 else
573         if test -z "$onto"
574         then
575                 empty_tree=$(git hash-object -t tree /dev/null)
576                 onto=$(git commit-tree $empty_tree </dev/null)
577                 squash_onto="$onto"
578         fi
579         unset upstream_name
580         unset upstream
581         test $# -gt 1 && usage
582         upstream_arg=--root
583 fi
584
585 # Make sure the branch to rebase onto is valid.
586 onto_name=${onto-"$upstream_name"}
587 case "$onto_name" in
588 *...*)
589         if      left=${onto_name%...*} right=${onto_name#*...} &&
590                 onto=$(git merge-base --all ${left:-HEAD} ${right:-HEAD})
591         then
592                 case "$onto" in
593                 ?*"$LF"?*)
594                         die "$(eval_gettext "\$onto_name: there are more than one merge bases")"
595                         ;;
596                 '')
597                         die "$(eval_gettext "\$onto_name: there is no merge base")"
598                         ;;
599                 esac
600         else
601                 die "$(eval_gettext "\$onto_name: there is no merge base")"
602         fi
603         ;;
604 *)
605         onto=$(peel_committish "$onto_name") ||
606         die "$(eval_gettext "Does not point to a valid commit: \$onto_name")"
607         ;;
608 esac
609
610 # If the branch to rebase is given, that is the branch we will rebase
611 # $branch_name -- branch/commit being rebased, or HEAD (already detached)
612 # $orig_head -- commit object name of tip of the branch before rebasing
613 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
614 switch_to=
615 case "$#" in
616 1)
617         # Is it "rebase other $branchname" or "rebase other $commit"?
618         branch_name="$1"
619         switch_to="$1"
620
621         # Is it a local branch?
622         if git show-ref --verify --quiet -- "refs/heads/$branch_name" &&
623            orig_head=$(git rev-parse -q --verify "refs/heads/$branch_name")
624         then
625                 head_name="refs/heads/$branch_name"
626         # If not is it a valid ref (branch or commit)?
627         elif orig_head=$(git rev-parse -q --verify "$branch_name")
628         then
629                 head_name="detached HEAD"
630
631         else
632                 die "$(eval_gettext "fatal: no such branch/commit '\$branch_name'")"
633         fi
634         ;;
635 0)
636         # Do not need to switch branches, we are already on it.
637         if branch_name=$(git symbolic-ref -q HEAD)
638         then
639                 head_name=$branch_name
640                 branch_name=$(expr "z$branch_name" : 'zrefs/heads/\(.*\)')
641         else
642                 head_name="detached HEAD"
643                 branch_name=HEAD
644         fi
645         orig_head=$(git rev-parse --verify HEAD) || exit
646         ;;
647 *)
648         die "BUG: unexpected number of arguments left to parse"
649         ;;
650 esac
651
652 if test "$fork_point" = t
653 then
654         new_upstream=$(git merge-base --fork-point "$upstream_name" \
655                         "${switch_to:-HEAD}")
656         if test -n "$new_upstream"
657         then
658                 restrict_revision=$new_upstream
659         fi
660 fi
661
662 if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null
663 then
664         stash_sha1=$(git stash create "autostash") ||
665         die "$(gettext 'Cannot autostash')"
666
667         mkdir -p "$state_dir" &&
668         echo $stash_sha1 >"$state_dir/autostash" &&
669         stash_abbrev=$(git rev-parse --short $stash_sha1) &&
670         echo "$(eval_gettext 'Created autostash: $stash_abbrev')" &&
671         git reset --hard
672 fi
673
674 require_clean_work_tree "rebase" "$(gettext "Please commit or stash them.")"
675
676 # Now we are rebasing commits $upstream..$orig_head (or with --root,
677 # everything leading up to $orig_head) on top of $onto
678
679 # Check if we are already based on $onto with linear history,
680 # but this should be done only when upstream and onto are the same
681 # and if this is not an interactive rebase.
682 mb=$(git merge-base "$onto" "$orig_head")
683 if test -z "$interactive_rebase" && test "$upstream" = "$onto" &&
684         test "$mb" = "$onto" && test -z "$restrict_revision" &&
685         # linear history?
686         ! (git rev-list --parents "$onto".."$orig_head" | sane_grep " .* ") > /dev/null
687 then
688         if test -z "$force_rebase"
689         then
690                 # Lazily switch to the target branch if needed...
691                 test -z "$switch_to" ||
692                 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $switch_to" \
693                         git checkout -q "$switch_to" --
694                 if test "$branch_name" = "HEAD" &&
695                          ! git symbolic-ref -q HEAD
696                 then
697                         say "$(eval_gettext "HEAD is up to date.")"
698                 else
699                         say "$(eval_gettext "Current branch \$branch_name is up to date.")"
700                 fi
701                 finish_rebase
702                 exit 0
703         else
704                 if test "$branch_name" = "HEAD" &&
705                          ! git symbolic-ref -q HEAD
706                 then
707                         say "$(eval_gettext "HEAD is up to date, rebase forced.")"
708                 else
709                         say "$(eval_gettext "Current branch \$branch_name is up to date, rebase forced.")"
710                 fi
711         fi
712 fi
713
714 # If a hook exists, give it a chance to interrupt
715 run_pre_rebase_hook "$upstream_arg" "$@"
716
717 if test -n "$diffstat"
718 then
719         if test -n "$verbose"
720         then
721                 if test -z "$mb"
722                 then
723                         echo "$(eval_gettext "Changes to \$onto:")"
724                 else
725                         echo "$(eval_gettext "Changes from \$mb to \$onto:")"
726                 fi
727         fi
728         mb_tree="${mb:-$(git hash-object -t tree /dev/null)}"
729         # We want color (if set), but no pager
730         GIT_PAGER='' git diff --stat --summary "$mb_tree" "$onto"
731 fi
732
733 test -n "$interactive_rebase" && run_specific_rebase
734
735 # Detach HEAD and reset the tree
736 say "$(gettext "First, rewinding head to replay your work on top of it...")"
737
738 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name" \
739         git checkout -q "$onto^0" || die "could not detach HEAD"
740 git update-ref ORIG_HEAD $orig_head
741
742 # If the $onto is a proper descendant of the tip of the branch, then
743 # we just fast-forwarded.
744 if test "$mb" = "$orig_head"
745 then
746         say "$(eval_gettext "Fast-forwarded \$branch_name to \$onto_name.")"
747         move_to_original_branch
748         finish_rebase
749         exit 0
750 fi
751
752 if test -n "$rebase_root"
753 then
754         revisions="$onto..$orig_head"
755 else
756         revisions="${restrict_revision-$upstream}..$orig_head"
757 fi
758
759 run_specific_rebase