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