Merge branch 'jk/add-ignore-errors-bit-assignment-fix'
[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 y=!                same as --reschedule-failed-exec -x
30 k,keep-empty       preserve empty commits during rebase
31 allow-empty-message allow rebasing commits with empty messages
32 stat!              display a diffstat of what changed upstream
33 n,no-stat!         do not show diffstat of what changed upstream
34 verify             allow pre-rebase hook to run
35 rerere-autoupdate  allow rerere to update index with resolved conflicts
36 root!              rebase all reachable commits up to the root(s)
37 autosquash         move commits that begin with squash!/fixup! under -i
38 signoff            add a Signed-off-by: line to each commit
39 committer-date-is-author-date! passed to 'git am'
40 ignore-date!       passed to 'git am'
41 whitespace=!       passed to 'git apply'
42 ignore-whitespace! passed to 'git apply'
43 C=!                passed to 'git apply'
44 S,gpg-sign?        GPG-sign commits
45  Actions:
46 continue!          continue
47 abort!             abort and check out the original branch
48 skip!              skip current patch and continue
49 edit-todo!         edit the todo list during an interactive rebase
50 quit!              abort but keep HEAD where it is
51 show-current-patch! show the patch file being applied or merged
52 reschedule-failed-exec automatically reschedule failed exec commands
53 "
54 . git-sh-setup
55 set_reflog_action rebase
56 require_work_tree_exists
57 cd_to_toplevel
58
59 LF='
60 '
61 ok_to_skip_pre_rebase=
62
63 squash_onto=
64 unset onto
65 unset restrict_revision
66 cmd=
67 strategy=
68 strategy_opts=
69 do_merge=
70 merge_dir="$GIT_DIR"/rebase-merge
71 apply_dir="$GIT_DIR"/rebase-apply
72 verbose=
73 diffstat=
74 test "$(git config --bool rebase.stat)" = true && diffstat=t
75 autostash="$(git config --bool rebase.autostash || echo false)"
76 fork_point=auto
77 git_am_opt=
78 git_format_patch_opt=
79 rebase_root=
80 force_rebase=
81 allow_rerere_autoupdate=
82 # Non-empty if a rebase was in progress when 'git rebase' was invoked
83 in_progress=
84 # One of {am, merge, interactive}
85 type=
86 # One of {"$GIT_DIR"/rebase-apply, "$GIT_DIR"/rebase-merge}
87 state_dir=
88 # One of {'', continue, skip, abort}, as parsed from command line
89 action=
90 rebase_merges=
91 rebase_cousins=
92 preserve_merges=
93 autosquash=
94 keep_empty=
95 allow_empty_message=--allow-empty-message
96 signoff=
97 reschedule_failed_exec=
98 test "$(git config --bool rebase.autosquash)" = "true" && autosquash=t
99 case "$(git config --bool commit.gpgsign)" in
100 true)   gpg_sign_opt=-S ;;
101 *)      gpg_sign_opt= ;;
102 esac
103 test "$(git config --bool rebase.reschedulefailedexec)" = "true" &&
104 reschedule_failed_exec=--reschedule-failed-exec
105 . git-rebase--common
106
107 read_basic_state () {
108         test -f "$state_dir/head-name" &&
109         test -f "$state_dir/onto" &&
110         head_name=$(cat "$state_dir"/head-name) &&
111         onto=$(cat "$state_dir"/onto) &&
112         # We always write to orig-head, but interactive rebase used to write to
113         # head. Fall back to reading from head to cover for the case that the
114         # user upgraded git with an ongoing interactive rebase.
115         if test -f "$state_dir"/orig-head
116         then
117                 orig_head=$(cat "$state_dir"/orig-head)
118         else
119                 orig_head=$(cat "$state_dir"/head)
120         fi &&
121         GIT_QUIET=$(cat "$state_dir"/quiet) &&
122         test -f "$state_dir"/verbose && verbose=t
123         test -f "$state_dir"/strategy && strategy="$(cat "$state_dir"/strategy)"
124         test -f "$state_dir"/strategy_opts &&
125                 strategy_opts="$(cat "$state_dir"/strategy_opts)"
126         test -f "$state_dir"/allow_rerere_autoupdate &&
127                 allow_rerere_autoupdate="$(cat "$state_dir"/allow_rerere_autoupdate)"
128         test -f "$state_dir"/gpg_sign_opt &&
129                 gpg_sign_opt="$(cat "$state_dir"/gpg_sign_opt)"
130         test -f "$state_dir"/signoff && {
131                 signoff="$(cat "$state_dir"/signoff)"
132                 force_rebase=t
133         }
134         test -f "$state_dir"/reschedule-failed-exec &&
135                 reschedule_failed_exec=t
136 }
137
138 finish_rebase () {
139         rm -f "$(git rev-parse --git-path REBASE_HEAD)"
140         apply_autostash &&
141         { git gc --auto || true; } &&
142         rm -rf "$state_dir"
143 }
144
145 run_interactive () {
146         GIT_CHERRY_PICK_HELP="$resolvemsg"
147         export GIT_CHERRY_PICK_HELP
148
149         test -n "$keep_empty" && keep_empty="--keep-empty"
150         test -n "$rebase_merges" && rebase_merges="--rebase-merges"
151         test -n "$rebase_cousins" && rebase_cousins="--rebase-cousins"
152         test -n "$autosquash" && autosquash="--autosquash"
153         test -n "$verbose" && verbose="--verbose"
154         test -n "$force_rebase" && force_rebase="--no-ff"
155         test -n "$restrict_revision" && \
156                 restrict_revision="--restrict-revision=^$restrict_revision"
157         test -n "$upstream" && upstream="--upstream=$upstream"
158         test -n "$onto" && onto="--onto=$onto"
159         test -n "$squash_onto" && squash_onto="--squash-onto=$squash_onto"
160         test -n "$onto_name" && onto_name="--onto-name=$onto_name"
161         test -n "$head_name" && head_name="--head-name=$head_name"
162         test -n "$strategy" && strategy="--strategy=$strategy"
163         test -n "$strategy_opts" && strategy_opts="--strategy-opts=$strategy_opts"
164         test -n "$switch_to" && switch_to="--switch-to=$switch_to"
165         test -n "$cmd" && cmd="--cmd=$cmd"
166         test -n "$action" && action="--$action"
167
168         exec git rebase--interactive "$action" "$keep_empty" "$rebase_merges" "$rebase_cousins" \
169                 "$upstream" "$onto" "$squash_onto" "$restrict_revision" \
170                 "$allow_empty_message" "$autosquash" "$verbose" \
171                 "$force_rebase" "$onto_name" "$head_name" "$strategy" \
172                 "$strategy_opts" "$cmd" "$switch_to" \
173                 "$allow_rerere_autoupdate" "$gpg_sign_opt" "$signoff" \
174                 "$reschedule_failed_exec"
175 }
176
177 run_specific_rebase () {
178         if [ "$interactive_rebase" = implied ]; then
179                 GIT_EDITOR=:
180                 export GIT_EDITOR
181                 autosquash=
182         fi
183
184         if test -n "$interactive_rebase" -a -z "$preserve_merges"
185         then
186                 run_interactive
187         else
188                 . git-rebase--$type
189
190                 if test -z "$preserve_merges"
191                 then
192                         git_rebase__$type
193                 else
194                         git_rebase__preserve_merges
195                 fi
196         fi
197
198         ret=$?
199         if test $ret -eq 0
200         then
201                 finish_rebase
202         elif test $ret -eq 2 # special exit status for rebase -p
203         then
204                 apply_autostash &&
205                 rm -rf "$state_dir" &&
206                 die "Nothing to do"
207         fi
208         exit $ret
209 }
210
211 run_pre_rebase_hook () {
212         if test -z "$ok_to_skip_pre_rebase" &&
213            test -x "$(git rev-parse --git-path hooks/pre-rebase)"
214         then
215                 "$(git rev-parse --git-path hooks/pre-rebase)" ${1+"$@"} ||
216                 die "$(gettext "The pre-rebase hook refused to rebase.")"
217         fi
218 }
219
220 test -f "$apply_dir"/applying &&
221         die "$(gettext "It looks like 'git am' is in progress. Cannot rebase.")"
222
223 if test -d "$apply_dir"
224 then
225         type=am
226         state_dir="$apply_dir"
227 elif test -d "$merge_dir"
228 then
229         if test -d "$merge_dir"/rewritten
230         then
231                 type=preserve-merges
232                 interactive_rebase=explicit
233                 preserve_merges=t
234         elif test -f "$merge_dir"/interactive
235         then
236                 type=interactive
237                 interactive_rebase=explicit
238         else
239                 type=merge
240         fi
241         state_dir="$merge_dir"
242 fi
243 test -n "$type" && in_progress=t
244
245 total_argc=$#
246 while test $# != 0
247 do
248         case "$1" in
249         --no-verify)
250                 ok_to_skip_pre_rebase=yes
251                 ;;
252         --verify)
253                 ok_to_skip_pre_rebase=
254                 ;;
255         --continue|--skip|--abort|--quit|--edit-todo|--show-current-patch)
256                 test $total_argc -eq 2 || usage
257                 action=${1##--}
258                 ;;
259         --onto=*)
260                 onto="${1#--onto=}"
261                 ;;
262         --exec=*)
263                 cmd="${cmd}exec ${1#--exec=}${LF}"
264                 test -z "$interactive_rebase" && interactive_rebase=implied
265                 ;;
266         -y*)
267                 reschedule_failed_exec=--reschedule-failed-exec
268                 cmd="${cmd}exec ${1#-y}${LF}"
269                 test -z "$interactive_rebase" && interactive_rebase=implied
270                 ;;
271         --interactive)
272                 interactive_rebase=explicit
273                 ;;
274         --keep-empty)
275                 keep_empty=yes
276                 ;;
277         --allow-empty-message)
278                 allow_empty_message=--allow-empty-message
279                 ;;
280         --no-keep-empty)
281                 keep_empty=
282                 ;;
283         --rebase-merges)
284                 rebase_merges=t
285                 test -z "$interactive_rebase" && interactive_rebase=implied
286                 ;;
287         --rebase-merges=*)
288                 rebase_merges=t
289                 case "${1#*=}" in
290                 rebase-cousins) rebase_cousins=t;;
291                 no-rebase-cousins) rebase_cousins=;;
292                 *) die "Unknown mode: $1";;
293                 esac
294                 test -z "$interactive_rebase" && interactive_rebase=implied
295                 ;;
296         --preserve-merges)
297                 preserve_merges=t
298                 test -z "$interactive_rebase" && interactive_rebase=implied
299                 ;;
300         --autosquash)
301                 autosquash=t
302                 ;;
303         --no-autosquash)
304                 autosquash=
305                 ;;
306         --fork-point)
307                 fork_point=t
308                 ;;
309         --no-fork-point)
310                 fork_point=
311                 ;;
312         --merge)
313                 do_merge=t
314                 ;;
315         --strategy-option=*)
316                 strategy_opts="$strategy_opts $(git rev-parse --sq-quote "--${1#--strategy-option=}" | sed -e s/^.//)"
317                 do_merge=t
318                 test -z "$strategy" && strategy=recursive
319                 ;;
320         --strategy=*)
321                 strategy="${1#--strategy=}"
322                 do_merge=t
323                 ;;
324         --no-stat)
325                 diffstat=
326                 ;;
327         --stat)
328                 diffstat=t
329                 ;;
330         --autostash)
331                 autostash=true
332                 ;;
333         --no-autostash)
334                 autostash=false
335                 ;;
336         --verbose)
337                 verbose=t
338                 diffstat=t
339                 GIT_QUIET=
340                 ;;
341         --quiet)
342                 GIT_QUIET=t
343                 git_am_opt="$git_am_opt -q"
344                 verbose=
345                 diffstat=
346                 ;;
347         --whitespace=*)
348                 git_am_opt="$git_am_opt --whitespace=${1#--whitespace=}"
349                 case "${1#--whitespace=}" in
350                 fix|strip)
351                         force_rebase=t
352                         ;;
353                 warn|nowarn|error|error-all)
354                         ;; # okay, known whitespace option
355                 *)
356                         die "fatal: Invalid whitespace option: '${1#*=}'"
357                         ;;
358                 esac
359                 ;;
360         --ignore-whitespace)
361                 git_am_opt="$git_am_opt $1"
362                 ;;
363         --signoff)
364                 signoff=--signoff
365                 ;;
366         --no-signoff)
367                 signoff=
368                 ;;
369         --committer-date-is-author-date|--ignore-date)
370                 git_am_opt="$git_am_opt $1"
371                 force_rebase=t
372                 ;;
373         -C*[!0-9]*)
374                 die "fatal: switch \`C' expects a numerical value"
375                 ;;
376         -C*)
377                 git_am_opt="$git_am_opt $1"
378                 ;;
379         --root)
380                 rebase_root=t
381                 ;;
382         --force-rebase|--no-ff)
383                 force_rebase=t
384                 ;;
385         --rerere-autoupdate|--no-rerere-autoupdate)
386                 allow_rerere_autoupdate="$1"
387                 ;;
388         --gpg-sign)
389                 gpg_sign_opt=-S
390                 ;;
391         --gpg-sign=*)
392                 gpg_sign_opt="-S${1#--gpg-sign=}"
393                 ;;
394         --reschedule-failed-exec)
395                 reschedule_failed_exec=--reschedule-failed-exec
396                 ;;
397         --no-reschedule-failed-exec)
398                 reschedule_failed_exec=
399                 ;;
400         --)
401                 shift
402                 break
403                 ;;
404         *)
405                 usage
406                 ;;
407         esac
408         shift
409 done
410 test $# -gt 2 && usage
411
412 if test -n "$action"
413 then
414         test -z "$in_progress" && die "$(gettext "No rebase in progress?")"
415         # Only interactive rebase uses detailed reflog messages
416         if test -n "$interactive_rebase" && test "$GIT_REFLOG_ACTION" = rebase
417         then
418                 GIT_REFLOG_ACTION="rebase -i ($action)"
419                 export GIT_REFLOG_ACTION
420         fi
421 fi
422
423 if test "$action" = "edit-todo" && test -z "$interactive_rebase"
424 then
425         die "$(gettext "The --edit-todo action can only be used during interactive rebase.")"
426 fi
427
428 case "$action" in
429 continue)
430         # Sanity check
431         git rev-parse --verify HEAD >/dev/null ||
432                 die "$(gettext "Cannot read HEAD")"
433         git update-index --ignore-submodules --refresh &&
434         git diff-files --quiet --ignore-submodules || {
435                 echo "$(gettext "You must edit all merge conflicts and then
436 mark them as resolved using git add")"
437                 exit 1
438         }
439         read_basic_state
440         run_specific_rebase
441         ;;
442 skip)
443         output git reset --hard HEAD || exit $?
444         read_basic_state
445         run_specific_rebase
446         ;;
447 abort)
448         git rerere clear
449         read_basic_state
450         case "$head_name" in
451         refs/*)
452                 git symbolic-ref -m "rebase: aborting" HEAD $head_name ||
453                 die "$(eval_gettext "Could not move back to \$head_name")"
454                 ;;
455         esac
456         output git reset --hard $orig_head
457         finish_rebase
458         exit
459         ;;
460 quit)
461         exec rm -rf "$state_dir"
462         ;;
463 edit-todo)
464         run_specific_rebase
465         ;;
466 show-current-patch)
467         run_specific_rebase
468         die "BUG: run_specific_rebase is not supposed to return here"
469         ;;
470 esac
471
472 # Make sure no rebase is in progress
473 if test -n "$in_progress"
474 then
475         state_dir_base=${state_dir##*/}
476         cmd_live_rebase="git rebase (--continue | --abort | --skip)"
477         cmd_clear_stale_rebase="rm -fr \"$state_dir\""
478         die "
479 $(eval_gettext 'It seems that there is already a $state_dir_base directory, and
480 I wonder if you are in the middle of another rebase.  If that is the
481 case, please try
482         $cmd_live_rebase
483 If that is not the case, please
484         $cmd_clear_stale_rebase
485 and run me again.  I am stopping in case you still have something
486 valuable there.')"
487 fi
488
489 if test -n "$rebase_root" && test -z "$onto"
490 then
491         test -z "$interactive_rebase" && interactive_rebase=implied
492 fi
493
494 if test -n "$keep_empty"
495 then
496         test -z "$interactive_rebase" && interactive_rebase=implied
497 fi
498
499 if test -n "$interactive_rebase"
500 then
501         if test -z "$preserve_merges"
502         then
503                 type=interactive
504         else
505                 type=preserve-merges
506         fi
507
508         state_dir="$merge_dir"
509 elif test -n "$do_merge"
510 then
511         type=merge
512         state_dir="$merge_dir"
513 else
514         type=am
515         state_dir="$apply_dir"
516 fi
517
518 if test -t 2 && test -z "$GIT_QUIET"
519 then
520         git_format_patch_opt="$git_format_patch_opt --progress"
521 fi
522
523 if test -n "$git_am_opt"; then
524         incompatible_opts=$(echo " $git_am_opt " | \
525                             sed -e 's/ -q / /g' -e 's/^ \(.*\) $/\1/')
526         if test -n "$interactive_rebase"
527         then
528                 if test -n "$incompatible_opts"
529                 then
530                         die "$(gettext "error: cannot combine interactive options (--interactive, --exec, --rebase-merges, --preserve-merges, --keep-empty, --root + --onto) with am options ($incompatible_opts)")"
531                 fi
532         fi
533         if test -n "$do_merge"; then
534                 if test -n "$incompatible_opts"
535                 then
536                         die "$(gettext "error: cannot combine merge options (--merge, --strategy, --strategy-option) with am options ($incompatible_opts)")"
537                 fi
538         fi
539 fi
540
541 if test -n "$signoff"
542 then
543         test -n "$preserve_merges" &&
544                 die "$(gettext "error: cannot combine '--signoff' with '--preserve-merges'")"
545         git_am_opt="$git_am_opt $signoff"
546         force_rebase=t
547 fi
548
549 if test -n "$preserve_merges"
550 then
551         # Note: incompatibility with --signoff handled in signoff block above
552         # Note: incompatibility with --interactive is just a strong warning;
553         #       git-rebase.txt caveats with "unless you know what you are doing"
554         test -n "$rebase_merges" &&
555                 die "$(gettext "error: cannot combine '--preserve-merges' with '--rebase-merges'")"
556
557         test -n "$reschedule_failed_exec" &&
558                 die "$(gettext "error: cannot combine '--preserve-merges' with '--reschedule-failed-exec'")"
559 fi
560
561 if test -n "$rebase_merges"
562 then
563         test -n "$strategy_opts" &&
564                 die "$(gettext "error: cannot combine '--rebase-merges' with '--strategy-option'")"
565         test -n "$strategy" &&
566                 die "$(gettext "error: cannot combine '--rebase-merges' with '--strategy'")"
567 fi
568
569 if test -z "$rebase_root"
570 then
571         case "$#" in
572         0)
573                 if ! upstream_name=$(git rev-parse --symbolic-full-name \
574                         --verify -q @{upstream} 2>/dev/null)
575                 then
576                         . git-parse-remote
577                         error_on_missing_default_upstream "rebase" "rebase" \
578                                 "against" "git rebase $(gettext '<branch>')"
579                 fi
580
581                 test "$fork_point" = auto && fork_point=t
582                 ;;
583         *)      upstream_name="$1"
584                 if test "$upstream_name" = "-"
585                 then
586                         upstream_name="@{-1}"
587                 fi
588                 shift
589                 ;;
590         esac
591         upstream=$(peel_committish "${upstream_name}") ||
592         die "$(eval_gettext "invalid upstream '\$upstream_name'")"
593         upstream_arg="$upstream_name"
594 else
595         if test -z "$onto"
596         then
597                 empty_tree=$(git hash-object -t tree /dev/null)
598                 onto=$(git commit-tree $empty_tree </dev/null)
599                 squash_onto="$onto"
600         fi
601         unset upstream_name
602         unset upstream
603         test $# -gt 1 && usage
604         upstream_arg=--root
605 fi
606
607 # Make sure the branch to rebase onto is valid.
608 onto_name=${onto-"$upstream_name"}
609 case "$onto_name" in
610 *...*)
611         if      left=${onto_name%...*} right=${onto_name#*...} &&
612                 onto=$(git merge-base --all ${left:-HEAD} ${right:-HEAD})
613         then
614                 case "$onto" in
615                 ?*"$LF"?*)
616                         die "$(eval_gettext "\$onto_name: there are more than one merge bases")"
617                         ;;
618                 '')
619                         die "$(eval_gettext "\$onto_name: there is no merge base")"
620                         ;;
621                 esac
622         else
623                 die "$(eval_gettext "\$onto_name: there is no merge base")"
624         fi
625         ;;
626 *)
627         onto=$(peel_committish "$onto_name") ||
628         die "$(eval_gettext "Does not point to a valid commit: \$onto_name")"
629         ;;
630 esac
631
632 # If the branch to rebase is given, that is the branch we will rebase
633 # $branch_name -- branch/commit being rebased, or HEAD (already detached)
634 # $orig_head -- commit object name of tip of the branch before rebasing
635 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
636 switch_to=
637 case "$#" in
638 1)
639         # Is it "rebase other $branchname" or "rebase other $commit"?
640         branch_name="$1"
641         switch_to="$1"
642
643         # Is it a local branch?
644         if git show-ref --verify --quiet -- "refs/heads/$branch_name" &&
645            orig_head=$(git rev-parse -q --verify "refs/heads/$branch_name")
646         then
647                 head_name="refs/heads/$branch_name"
648         # If not is it a valid ref (branch or commit)?
649         elif orig_head=$(git rev-parse -q --verify "$branch_name")
650         then
651                 head_name="detached HEAD"
652
653         else
654                 die "$(eval_gettext "fatal: no such branch/commit '\$branch_name'")"
655         fi
656         ;;
657 0)
658         # Do not need to switch branches, we are already on it.
659         if branch_name=$(git symbolic-ref -q HEAD)
660         then
661                 head_name=$branch_name
662                 branch_name=$(expr "z$branch_name" : 'zrefs/heads/\(.*\)')
663         else
664                 head_name="detached HEAD"
665                 branch_name=HEAD
666         fi
667         orig_head=$(git rev-parse --verify HEAD) || exit
668         ;;
669 *)
670         die "BUG: unexpected number of arguments left to parse"
671         ;;
672 esac
673
674 if test "$fork_point" = t
675 then
676         new_upstream=$(git merge-base --fork-point "$upstream_name" \
677                         "${switch_to:-HEAD}")
678         if test -n "$new_upstream"
679         then
680                 restrict_revision=$new_upstream
681         fi
682 fi
683
684 if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null
685 then
686         stash_sha1=$(git stash create "autostash") ||
687         die "$(gettext 'Cannot autostash')"
688
689         mkdir -p "$state_dir" &&
690         echo $stash_sha1 >"$state_dir/autostash" &&
691         stash_abbrev=$(git rev-parse --short $stash_sha1) &&
692         echo "$(eval_gettext 'Created autostash: $stash_abbrev')" &&
693         git reset --hard
694 fi
695
696 require_clean_work_tree "rebase" "$(gettext "Please commit or stash them.")"
697
698 # Now we are rebasing commits $upstream..$orig_head (or with --root,
699 # everything leading up to $orig_head) on top of $onto
700
701 # Check if we are already based on $onto with linear history,
702 # but this should be done only when upstream and onto are the same
703 # and if this is not an interactive rebase.
704 mb=$(git merge-base "$onto" "$orig_head")
705 if test -z "$interactive_rebase" && test "$upstream" = "$onto" &&
706         test "$mb" = "$onto" && test -z "$restrict_revision" &&
707         # linear history?
708         ! (git rev-list --parents "$onto".."$orig_head" | sane_grep " .* ") > /dev/null
709 then
710         if test -z "$force_rebase"
711         then
712                 # Lazily switch to the target branch if needed...
713                 test -z "$switch_to" ||
714                 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $switch_to" \
715                         git checkout -q "$switch_to" --
716                 if test "$branch_name" = "HEAD" &&
717                          ! git symbolic-ref -q HEAD
718                 then
719                         say "$(eval_gettext "HEAD is up to date.")"
720                 else
721                         say "$(eval_gettext "Current branch \$branch_name is up to date.")"
722                 fi
723                 finish_rebase
724                 exit 0
725         else
726                 if test "$branch_name" = "HEAD" &&
727                          ! git symbolic-ref -q HEAD
728                 then
729                         say "$(eval_gettext "HEAD is up to date, rebase forced.")"
730                 else
731                         say "$(eval_gettext "Current branch \$branch_name is up to date, rebase forced.")"
732                 fi
733         fi
734 fi
735
736 # If a hook exists, give it a chance to interrupt
737 run_pre_rebase_hook "$upstream_arg" "$@"
738
739 if test -n "$diffstat"
740 then
741         if test -n "$verbose"
742         then
743                 if test -z "$mb"
744                 then
745                         echo "$(eval_gettext "Changes to \$onto:")"
746                 else
747                         echo "$(eval_gettext "Changes from \$mb to \$onto:")"
748                 fi
749         fi
750         mb_tree="${mb:-$(git hash-object -t tree /dev/null)}"
751         # We want color (if set), but no pager
752         GIT_PAGER='' git diff --stat --summary "$mb_tree" "$onto"
753 fi
754
755 test -n "$interactive_rebase" && run_specific_rebase
756
757 # Detach HEAD and reset the tree
758 say "$(gettext "First, rewinding head to replay your work on top of it...")"
759
760 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name" \
761         git checkout -q "$onto^0" || die "could not detach HEAD"
762 git update-ref ORIG_HEAD $orig_head
763
764 # If the $onto is a proper descendant of the tip of the branch, then
765 # we just fast-forwarded.
766 if test "$mb" = "$orig_head"
767 then
768         say "$(eval_gettext "Fast-forwarded \$branch_name to \$onto_name.")"
769         move_to_original_branch
770         finish_rebase
771         exit 0
772 fi
773
774 if test -n "$rebase_root"
775 then
776         revisions="$onto..$orig_head"
777 else
778         revisions="${restrict_revision-$upstream}..$orig_head"
779 fi
780
781 run_specific_rebase