Merge branch 'jn/fast-import-ondemand-checkpoint'
[git] / git-rebase.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano.
4 #
5
6 USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--no-ff] [--onto <newbase>] (<upstream>|--root) [<branch>] [--quiet | -q]'
7 LONG_USAGE='git-rebase replaces <branch> with a new branch of the
8 same name.  When the --onto option is provided the new branch starts
9 out with a HEAD equal to <newbase>, otherwise it is equal to <upstream>
10 It then attempts to create a new commit for each commit from the original
11 <branch> that does not exist in the <upstream> branch.
12
13 It is possible that a merge failure will prevent this process from being
14 completely automatic.  You will have to resolve any such merge failure
15 and run git rebase --continue.  Another option is to bypass the commit
16 that caused the merge failure with git rebase --skip.  To restore the
17 original <branch> and remove the .git/rebase-apply working files, use the
18 command git rebase --abort instead.
19
20 Note that if <branch> is not specified on the command line, the
21 currently checked out branch is used.
22
23 Example:       git-rebase master~1 topic
24
25         A---B---C topic                   A'\''--B'\''--C'\'' topic
26        /                   -->           /
27   D---E---F---G master          D---E---F---G master
28 '
29
30 SUBDIRECTORY_OK=Yes
31 OPTIONS_SPEC=
32 . git-sh-setup
33 set_reflog_action rebase
34 require_work_tree
35 cd_to_toplevel
36
37 LF='
38 '
39 OK_TO_SKIP_PRE_REBASE=
40 RESOLVEMSG="
41 When you have resolved this problem run \"git rebase --continue\".
42 If you would prefer to skip this patch, instead run \"git rebase --skip\".
43 To restore the original branch and stop rebasing run \"git rebase --abort\".
44 "
45 unset newbase
46 strategy=recursive
47 strategy_opts=
48 do_merge=
49 dotest="$GIT_DIR"/rebase-merge
50 prec=4
51 verbose=
52 diffstat=
53 test "$(git config --bool rebase.stat)" = true && diffstat=t
54 git_am_opt=
55 rebase_root=
56 force_rebase=
57 allow_rerere_autoupdate=
58
59 continue_merge () {
60         test -n "$prev_head" || die "prev_head must be defined"
61         test -d "$dotest" || die "$dotest directory does not exist"
62
63         unmerged=$(git ls-files -u)
64         if test -n "$unmerged"
65         then
66                 echo "You still have unmerged paths in your index"
67                 echo "did you forget to use git add?"
68                 die "$RESOLVEMSG"
69         fi
70
71         cmt=`cat "$dotest/current"`
72         if ! git diff-index --quiet --ignore-submodules HEAD --
73         then
74                 if ! git commit --no-verify -C "$cmt"
75                 then
76                         echo "Commit failed, please do not call \"git commit\""
77                         echo "directly, but instead do one of the following: "
78                         die "$RESOLVEMSG"
79                 fi
80                 if test -z "$GIT_QUIET"
81                 then
82                         printf "Committed: %0${prec}d " $msgnum
83                 fi
84                 echo "$cmt $(git rev-parse HEAD^0)" >> "$dotest/rewritten"
85         else
86                 if test -z "$GIT_QUIET"
87                 then
88                         printf "Already applied: %0${prec}d " $msgnum
89                 fi
90         fi
91         test -z "$GIT_QUIET" &&
92         GIT_PAGER='' git log --format=%s -1 "$cmt"
93
94         prev_head=`git rev-parse HEAD^0`
95         # save the resulting commit so we can read-tree on it later
96         echo "$prev_head" > "$dotest/prev_head"
97
98         # onto the next patch:
99         msgnum=$(($msgnum + 1))
100         echo "$msgnum" >"$dotest/msgnum"
101 }
102
103 call_merge () {
104         cmt="$(cat "$dotest/cmt.$1")"
105         echo "$cmt" > "$dotest/current"
106         hd=$(git rev-parse --verify HEAD)
107         cmt_name=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
108         msgnum=$(cat "$dotest/msgnum")
109         end=$(cat "$dotest/end")
110         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
111         eval GITHEAD_$hd='$(cat "$dotest/onto_name")'
112         export GITHEAD_$cmt GITHEAD_$hd
113         if test -n "$GIT_QUIET"
114         then
115                 GIT_MERGE_VERBOSITY=1 && export GIT_MERGE_VERBOSITY
116         fi
117         eval 'git-merge-$strategy' $strategy_opts '"$cmt^" -- "$hd" "$cmt"'
118         rv=$?
119         case "$rv" in
120         0)
121                 unset GITHEAD_$cmt GITHEAD_$hd
122                 return
123                 ;;
124         1)
125                 git rerere $allow_rerere_autoupdate
126                 die "$RESOLVEMSG"
127                 ;;
128         2)
129                 echo "Strategy: $rv $strategy failed, try another" 1>&2
130                 die "$RESOLVEMSG"
131                 ;;
132         *)
133                 die "Unknown exit code ($rv) from command:" \
134                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
135                 ;;
136         esac
137 }
138
139 move_to_original_branch () {
140         test -z "$head_name" &&
141                 head_name="$(cat "$dotest"/head-name)" &&
142                 onto="$(cat "$dotest"/onto)" &&
143                 orig_head="$(cat "$dotest"/orig-head)"
144         case "$head_name" in
145         refs/*)
146                 message="rebase finished: $head_name onto $onto"
147                 git update-ref -m "$message" \
148                         $head_name $(git rev-parse HEAD) $orig_head &&
149                 git symbolic-ref HEAD $head_name ||
150                 die "Could not move back to $head_name"
151                 ;;
152         esac
153 }
154
155 finish_rb_merge () {
156         move_to_original_branch
157         git notes copy --for-rewrite=rebase < "$dotest"/rewritten
158         if test -x "$GIT_DIR"/hooks/post-rewrite &&
159                 test -s "$dotest"/rewritten; then
160                 "$GIT_DIR"/hooks/post-rewrite rebase < "$dotest"/rewritten
161         fi
162         rm -r "$dotest"
163         say All done.
164 }
165
166 is_interactive () {
167         while test $# != 0
168         do
169                 case "$1" in
170                         -i|--interactive)
171                                 interactive_rebase=explicit
172                                 break
173                         ;;
174                         -p|--preserve-merges)
175                                 interactive_rebase=implied
176                         ;;
177                 esac
178                 shift
179         done
180
181         if [ "$interactive_rebase" = implied ]; then
182                 GIT_EDITOR=:
183                 export GIT_EDITOR
184         fi
185
186         test -n "$interactive_rebase" || test -f "$dotest"/interactive
187 }
188
189 run_pre_rebase_hook () {
190         if test -z "$OK_TO_SKIP_PRE_REBASE" &&
191            test -x "$GIT_DIR/hooks/pre-rebase"
192         then
193                 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} ||
194                 die "The pre-rebase hook refused to rebase."
195         fi
196 }
197
198 test -f "$GIT_DIR"/rebase-apply/applying &&
199         die 'It looks like git-am is in progress. Cannot rebase.'
200
201 is_interactive "$@" && exec git-rebase--interactive "$@"
202
203 while test $# != 0
204 do
205         case "$1" in
206         --no-verify)
207                 OK_TO_SKIP_PRE_REBASE=yes
208                 ;;
209         --verify)
210                 OK_TO_SKIP_PRE_REBASE=
211                 ;;
212         --continue)
213                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
214                         die "No rebase in progress?"
215
216                 git update-index --ignore-submodules --refresh &&
217                 git diff-files --quiet --ignore-submodules || {
218                         echo "You must edit all merge conflicts and then"
219                         echo "mark them as resolved using git add"
220                         exit 1
221                 }
222                 if test -d "$dotest"
223                 then
224                         prev_head=$(cat "$dotest/prev_head")
225                         end=$(cat "$dotest/end")
226                         msgnum=$(cat "$dotest/msgnum")
227                         onto=$(cat "$dotest/onto")
228                         GIT_QUIET=$(cat "$dotest/quiet")
229                         continue_merge
230                         while test "$msgnum" -le "$end"
231                         do
232                                 call_merge "$msgnum"
233                                 continue_merge
234                         done
235                         finish_rb_merge
236                         exit
237                 fi
238                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
239                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
240                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
241                 GIT_QUIET=$(cat "$GIT_DIR"/rebase-apply/quiet)
242                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
243                 move_to_original_branch
244                 exit
245                 ;;
246         --skip)
247                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
248                         die "No rebase in progress?"
249
250                 git reset --hard HEAD || exit $?
251                 if test -d "$dotest"
252                 then
253                         git rerere clear
254                         prev_head=$(cat "$dotest/prev_head")
255                         end=$(cat "$dotest/end")
256                         msgnum=$(cat "$dotest/msgnum")
257                         msgnum=$(($msgnum + 1))
258                         onto=$(cat "$dotest/onto")
259                         GIT_QUIET=$(cat "$dotest/quiet")
260                         while test "$msgnum" -le "$end"
261                         do
262                                 call_merge "$msgnum"
263                                 continue_merge
264                         done
265                         finish_rb_merge
266                         exit
267                 fi
268                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
269                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
270                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
271                 GIT_QUIET=$(cat "$GIT_DIR"/rebase-apply/quiet)
272                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
273                 move_to_original_branch
274                 exit
275                 ;;
276         --abort)
277                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
278                         die "No rebase in progress?"
279
280                 git rerere clear
281
282                 test -d "$dotest" || dotest="$GIT_DIR"/rebase-apply
283
284                 head_name="$(cat "$dotest"/head-name)" &&
285                 case "$head_name" in
286                 refs/*)
287                         git symbolic-ref HEAD $head_name ||
288                         die "Could not move back to $head_name"
289                         ;;
290                 esac
291                 git reset --hard $(cat "$dotest/orig-head")
292                 rm -r "$dotest"
293                 exit
294                 ;;
295         --onto)
296                 test 2 -le "$#" || usage
297                 newbase="$2"
298                 shift
299                 ;;
300         -M|-m|--m|--me|--mer|--merg|--merge)
301                 do_merge=t
302                 ;;
303         -X*|--strategy-option*)
304                 case "$#,$1" in
305                 1,-X|1,--strategy-option)
306                         usage ;;
307                 *,-X|*,--strategy-option)
308                         newopt="$2"
309                         shift ;;
310                 *,--strategy-option=*)
311                         newopt="$(expr " $1" : ' --strategy-option=\(.*\)')" ;;
312                 *,-X*)
313                         newopt="$(expr " $1" : ' -X\(.*\)')" ;;
314                 1,*)
315                         usage ;;
316                 esac
317                 strategy_opts="$strategy_opts $(git rev-parse --sq-quote "--$newopt")"
318                 do_merge=t
319                 ;;
320         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
321                 --strateg=*|--strategy=*|\
322         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
323                 case "$#,$1" in
324                 *,*=*)
325                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
326                 1,*)
327                         usage ;;
328                 *)
329                         strategy="$2"
330                         shift ;;
331                 esac
332                 do_merge=t
333                 ;;
334         -n|--no-stat)
335                 diffstat=
336                 ;;
337         --stat)
338                 diffstat=t
339                 ;;
340         -v|--verbose)
341                 verbose=t
342                 diffstat=t
343                 GIT_QUIET=
344                 ;;
345         -q|--quiet)
346                 GIT_QUIET=t
347                 git_am_opt="$git_am_opt -q"
348                 verbose=
349                 diffstat=
350                 ;;
351         --whitespace=*)
352                 git_am_opt="$git_am_opt $1"
353                 case "$1" in
354                 --whitespace=fix|--whitespace=strip)
355                         force_rebase=t
356                         ;;
357                 esac
358                 ;;
359         --ignore-whitespace)
360                 git_am_opt="$git_am_opt $1"
361                 ;;
362         --committer-date-is-author-date|--ignore-date)
363                 git_am_opt="$git_am_opt $1"
364                 force_rebase=t
365                 ;;
366         -C*)
367                 git_am_opt="$git_am_opt $1"
368                 ;;
369         --root)
370                 rebase_root=t
371                 ;;
372         -f|--f|--fo|--for|--forc|--force|--force-r|--force-re|--force-reb|--force-reba|--force-rebas|--force-rebase|--no-ff)
373                 force_rebase=t
374                 ;;
375         --rerere-autoupdate|--no-rerere-autoupdate)
376                 allow_rerere_autoupdate="$1"
377                 ;;
378         -*)
379                 usage
380                 ;;
381         *)
382                 break
383                 ;;
384         esac
385         shift
386 done
387 test $# -gt 2 && usage
388
389 if test $# -eq 0 && test -z "$rebase_root"
390 then
391         test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply || usage
392         test -d "$dotest" -o -f "$GIT_DIR"/rebase-apply/rebasing &&
393                 die 'A rebase is in progress, try --continue, --skip or --abort.'
394 fi
395
396 # Make sure we do not have $GIT_DIR/rebase-apply
397 if test -z "$do_merge"
398 then
399         if mkdir "$GIT_DIR"/rebase-apply 2>/dev/null
400         then
401                 rmdir "$GIT_DIR"/rebase-apply
402         else
403                 echo >&2 '
404 It seems that I cannot create a rebase-apply directory, and
405 I wonder if you are in the middle of patch application or another
406 rebase.  If that is not the case, please
407         rm -fr '"$GIT_DIR"'/rebase-apply
408 and run me again.  I am stopping in case you still have something
409 valuable there.'
410                 exit 1
411         fi
412 else
413         if test -d "$dotest"
414         then
415                 die "previous rebase directory $dotest still exists." \
416                         'Try git rebase (--continue | --abort | --skip)'
417         fi
418 fi
419
420 require_clean_work_tree "rebase" "Please commit or stash them."
421
422 if test -z "$rebase_root"
423 then
424         # The upstream head must be given.  Make sure it is valid.
425         upstream_name="$1"
426         shift
427         upstream=`git rev-parse --verify "${upstream_name}^0"` ||
428         die "invalid upstream $upstream_name"
429         unset root_flag
430         upstream_arg="$upstream_name"
431 else
432         test -z "$newbase" && die "--root must be used with --onto"
433         unset upstream_name
434         unset upstream
435         root_flag="--root"
436         upstream_arg="$root_flag"
437 fi
438
439 # Make sure the branch to rebase onto is valid.
440 onto_name=${newbase-"$upstream_name"}
441 case "$onto_name" in
442 *...*)
443         if      left=${onto_name%...*} right=${onto_name#*...} &&
444                 onto=$(git merge-base --all ${left:-HEAD} ${right:-HEAD})
445         then
446                 case "$onto" in
447                 ?*"$LF"?*)
448                         die "$onto_name: there are more than one merge bases"
449                         ;;
450                 '')
451                         die "$onto_name: there is no merge base"
452                         ;;
453                 esac
454         else
455                 die "$onto_name: there is no merge base"
456         fi
457         ;;
458 *)
459         onto=$(git rev-parse --verify "${onto_name}^0") || exit
460         ;;
461 esac
462
463 # If a hook exists, give it a chance to interrupt
464 run_pre_rebase_hook "$upstream_arg" "$@"
465
466 # If the branch to rebase is given, that is the branch we will rebase
467 # $branch_name -- branch being rebased, or HEAD (already detached)
468 # $orig_head -- commit object name of tip of the branch before rebasing
469 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
470 switch_to=
471 case "$#" in
472 1)
473         # Is it "rebase other $branchname" or "rebase other $commit"?
474         branch_name="$1"
475         switch_to="$1"
476
477         if git show-ref --verify --quiet -- "refs/heads/$1" &&
478            branch=$(git rev-parse -q --verify "refs/heads/$1")
479         then
480                 head_name="refs/heads/$1"
481         elif branch=$(git rev-parse -q --verify "$1")
482         then
483                 head_name="detached HEAD"
484         else
485                 usage
486         fi
487         ;;
488 *)
489         # Do not need to switch branches, we are already on it.
490         if branch_name=`git symbolic-ref -q HEAD`
491         then
492                 head_name=$branch_name
493                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
494         else
495                 head_name="detached HEAD"
496                 branch_name=HEAD ;# detached
497         fi
498         branch=$(git rev-parse --verify "${branch_name}^0") || exit
499         ;;
500 esac
501 orig_head=$branch
502
503 # Now we are rebasing commits $upstream..$branch (or with --root,
504 # everything leading up to $branch) on top of $onto
505
506 # Check if we are already based on $onto with linear history,
507 # but this should be done only when upstream and onto are the same.
508 mb=$(git merge-base "$onto" "$branch")
509 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
510         # linear history?
511         ! (git rev-list --parents "$onto".."$branch" | sane_grep " .* ") > /dev/null
512 then
513         if test -z "$force_rebase"
514         then
515                 # Lazily switch to the target branch if needed...
516                 test -z "$switch_to" || git checkout "$switch_to"
517                 say "Current branch $branch_name is up to date."
518                 exit 0
519         else
520                 say "Current branch $branch_name is up to date, rebase forced."
521         fi
522 fi
523
524 # Detach HEAD and reset the tree
525 say "First, rewinding head to replay your work on top of it..."
526 git checkout -q "$onto^0" || die "could not detach HEAD"
527 git update-ref ORIG_HEAD $branch
528
529 if test -n "$diffstat"
530 then
531         if test -n "$verbose"
532         then
533                 echo "Changes from $mb to $onto:"
534         fi
535         # We want color (if set), but no pager
536         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
537 fi
538
539 # If the $onto is a proper descendant of the tip of the branch, then
540 # we just fast-forwarded.
541 if test "$mb" = "$branch"
542 then
543         say "Fast-forwarded $branch_name to $onto_name."
544         move_to_original_branch
545         exit 0
546 fi
547
548 if test -n "$rebase_root"
549 then
550         revisions="$onto..$orig_head"
551 else
552         revisions="$upstream..$orig_head"
553 fi
554
555 if test -z "$do_merge"
556 then
557         git format-patch -k --stdout --full-index --ignore-if-in-upstream \
558                 --src-prefix=a/ --dst-prefix=b/ \
559                 --no-renames $root_flag "$revisions" |
560         git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
561         move_to_original_branch
562         ret=$?
563         test 0 != $ret -a -d "$GIT_DIR"/rebase-apply &&
564                 echo $head_name > "$GIT_DIR"/rebase-apply/head-name &&
565                 echo $onto > "$GIT_DIR"/rebase-apply/onto &&
566                 echo $orig_head > "$GIT_DIR"/rebase-apply/orig-head &&
567                 echo "$GIT_QUIET" > "$GIT_DIR"/rebase-apply/quiet
568         exit $ret
569 fi
570
571 # start doing a rebase with git-merge
572 # this is rename-aware if the recursive (default) strategy is used
573
574 mkdir -p "$dotest"
575 echo "$onto" > "$dotest/onto"
576 echo "$onto_name" > "$dotest/onto_name"
577 prev_head=$orig_head
578 echo "$prev_head" > "$dotest/prev_head"
579 echo "$orig_head" > "$dotest/orig-head"
580 echo "$head_name" > "$dotest/head-name"
581 echo "$GIT_QUIET" > "$dotest/quiet"
582
583 msgnum=0
584 for cmt in `git rev-list --reverse --no-merges "$revisions"`
585 do
586         msgnum=$(($msgnum + 1))
587         echo "$cmt" > "$dotest/cmt.$msgnum"
588 done
589
590 echo 1 >"$dotest/msgnum"
591 echo $msgnum >"$dotest/end"
592
593 end=$msgnum
594 msgnum=1
595
596 while test "$msgnum" -le "$end"
597 do
598         call_merge "$msgnum"
599         continue_merge
600 done
601
602 finish_rb_merge