Merge branch 'bc/reflog-fix' into js/reflog-delete
[git] / git-rebase.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano.
4 #
5
6 USAGE='[--interactive | -i] [-v] [--onto <newbase>] <upstream> [<branch>]'
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 .dotest working files, use the command
18 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.  You must be in the top
22 directory of your project to start (or continue) a rebase.
23
24 Example:       git-rebase master~1 topic
25
26         A---B---C topic                   A'\''--B'\''--C'\'' topic
27        /                   -->           /
28   D---E---F---G master          D---E---F---G master
29 '
30
31 SUBDIRECTORY_OK=Yes
32 OPTIONS_SPEC=
33 . git-sh-setup
34 set_reflog_action rebase
35 require_work_tree
36 cd_to_toplevel
37
38 RESOLVEMSG="
39 When you have resolved this problem run \"git rebase --continue\".
40 If you would prefer to skip this patch, instead run \"git rebase --skip\".
41 To restore the original branch and stop rebasing run \"git rebase --abort\".
42 "
43 unset newbase
44 strategy=recursive
45 do_merge=
46 dotest=$GIT_DIR/.dotest-merge
47 prec=4
48 verbose=
49 git_am_opt=
50
51 continue_merge () {
52         test -n "$prev_head" || die "prev_head must be defined"
53         test -d "$dotest" || die "$dotest directory does not exist"
54
55         unmerged=$(git ls-files -u)
56         if test -n "$unmerged"
57         then
58                 echo "You still have unmerged paths in your index"
59                 echo "did you forget to use git add?"
60                 die "$RESOLVEMSG"
61         fi
62
63         cmt=`cat "$dotest/current"`
64         if ! git diff-index --quiet HEAD --
65         then
66                 if ! git-commit -C "$cmt"
67                 then
68                         echo "Commit failed, please do not call \"git commit\""
69                         echo "directly, but instead do one of the following: "
70                         die "$RESOLVEMSG"
71                 fi
72                 printf "Committed: %0${prec}d " $msgnum
73         else
74                 printf "Already applied: %0${prec}d " $msgnum
75         fi
76         git rev-list --pretty=oneline -1 "$cmt" | sed -e 's/^[^ ]* //'
77
78         prev_head=`git rev-parse HEAD^0`
79         # save the resulting commit so we can read-tree on it later
80         echo "$prev_head" > "$dotest/prev_head"
81
82         # onto the next patch:
83         msgnum=$(($msgnum + 1))
84         echo "$msgnum" >"$dotest/msgnum"
85 }
86
87 call_merge () {
88         cmt="$(cat "$dotest/cmt.$1")"
89         echo "$cmt" > "$dotest/current"
90         hd=$(git rev-parse --verify HEAD)
91         cmt_name=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
92         msgnum=$(cat "$dotest/msgnum")
93         end=$(cat "$dotest/end")
94         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
95         eval GITHEAD_$hd='$(cat "$dotest/onto_name")'
96         export GITHEAD_$cmt GITHEAD_$hd
97         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
98         rv=$?
99         case "$rv" in
100         0)
101                 unset GITHEAD_$cmt GITHEAD_$hd
102                 return
103                 ;;
104         1)
105                 git rerere
106                 die "$RESOLVEMSG"
107                 ;;
108         2)
109                 echo "Strategy: $rv $strategy failed, try another" 1>&2
110                 die "$RESOLVEMSG"
111                 ;;
112         *)
113                 die "Unknown exit code ($rv) from command:" \
114                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
115                 ;;
116         esac
117 }
118
119 move_to_original_branch () {
120         test -z "$head_name" &&
121                 head_name="$(cat "$dotest"/head-name)" &&
122                 onto="$(cat "$dotest"/onto)" &&
123                 orig_head="$(cat "$dotest"/orig-head)"
124         case "$head_name" in
125         refs/*)
126                 message="rebase finished: $head_name onto $onto"
127                 git update-ref -m "$message" \
128                         $head_name $(git rev-parse HEAD) $orig_head &&
129                 git symbolic-ref HEAD $head_name ||
130                 die "Could not move back to $head_name"
131                 ;;
132         esac
133 }
134
135 finish_rb_merge () {
136         move_to_original_branch
137         rm -r "$dotest"
138         echo "All done."
139 }
140
141 is_interactive () {
142         test -f "$dotest"/interactive ||
143         while :; do case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
144                 shift
145         done && test -n "$1"
146 }
147
148 is_interactive "$@" && exec git-rebase--interactive "$@"
149
150 while test $# != 0
151 do
152         case "$1" in
153         --continue)
154                 git diff-files --quiet || {
155                         echo "You must edit all merge conflicts and then"
156                         echo "mark them as resolved using git add"
157                         exit 1
158                 }
159                 if test -d "$dotest"
160                 then
161                         prev_head=$(cat "$dotest/prev_head")
162                         end=$(cat "$dotest/end")
163                         msgnum=$(cat "$dotest/msgnum")
164                         onto=$(cat "$dotest/onto")
165                         continue_merge
166                         while test "$msgnum" -le "$end"
167                         do
168                                 call_merge "$msgnum"
169                                 continue_merge
170                         done
171                         finish_rb_merge
172                         exit
173                 fi
174                 head_name=$(cat .dotest/head-name) &&
175                 onto=$(cat .dotest/onto) &&
176                 orig_head=$(cat .dotest/orig-head) &&
177                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
178                 move_to_original_branch
179                 exit
180                 ;;
181         --skip)
182                 git reset --hard HEAD || exit $?
183                 if test -d "$dotest"
184                 then
185                         git rerere clear
186                         prev_head=$(cat "$dotest/prev_head")
187                         end=$(cat "$dotest/end")
188                         msgnum=$(cat "$dotest/msgnum")
189                         msgnum=$(($msgnum + 1))
190                         onto=$(cat "$dotest/onto")
191                         while test "$msgnum" -le "$end"
192                         do
193                                 call_merge "$msgnum"
194                                 continue_merge
195                         done
196                         finish_rb_merge
197                         exit
198                 fi
199                 head_name=$(cat .dotest/head-name) &&
200                 onto=$(cat .dotest/onto) &&
201                 orig_head=$(cat .dotest/orig-head) &&
202                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
203                 move_to_original_branch
204                 exit
205                 ;;
206         --abort)
207                 git rerere clear
208                 if test -d "$dotest"
209                 then
210                         move_to_original_branch
211                         rm -r "$dotest"
212                 elif test -d .dotest
213                 then
214                         dotest=.dotest
215                         move_to_original_branch
216                         rm -r .dotest
217                 else
218                         die "No rebase in progress?"
219                 fi
220                 git reset --hard ORIG_HEAD
221                 exit
222                 ;;
223         --onto)
224                 test 2 -le "$#" || usage
225                 newbase="$2"
226                 shift
227                 ;;
228         -M|-m|--m|--me|--mer|--merg|--merge)
229                 do_merge=t
230                 ;;
231         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
232                 --strateg=*|--strategy=*|\
233         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
234                 case "$#,$1" in
235                 *,*=*)
236                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
237                 1,*)
238                         usage ;;
239                 *)
240                         strategy="$2"
241                         shift ;;
242                 esac
243                 do_merge=t
244                 ;;
245         -v|--verbose)
246                 verbose=t
247                 ;;
248         --whitespace=*)
249                 git_am_opt="$git_am_opt $1"
250                 ;;
251         -C*)
252                 git_am_opt="$git_am_opt $1"
253                 ;;
254         -*)
255                 usage
256                 ;;
257         *)
258                 break
259                 ;;
260         esac
261         shift
262 done
263
264 # Make sure we do not have .dotest
265 if test -z "$do_merge"
266 then
267         if mkdir .dotest
268         then
269                 rmdir .dotest
270         else
271                 echo >&2 '
272 It seems that I cannot create a .dotest directory, and I wonder if you
273 are in the middle of patch application or another rebase.  If that is not
274 the case, please rm -fr .dotest and run me again.  I am stopping in case
275 you still have something valuable there.'
276                 exit 1
277         fi
278 else
279         if test -d "$dotest"
280         then
281                 die "previous dotest directory $dotest still exists." \
282                         'try git-rebase < --continue | --abort >'
283         fi
284 fi
285
286 # The tree must be really really clean.
287 git update-index --refresh || exit
288 diff=$(git diff-index --cached --name-status -r HEAD --)
289 case "$diff" in
290 ?*)     echo "cannot rebase: your index is not up-to-date"
291         echo "$diff"
292         exit 1
293         ;;
294 esac
295
296 # The upstream head must be given.  Make sure it is valid.
297 upstream_name="$1"
298 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
299     die "invalid upstream $upstream_name"
300
301 # Make sure the branch to rebase onto is valid.
302 onto_name=${newbase-"$upstream_name"}
303 onto=$(git rev-parse --verify "${onto_name}^0") || exit
304
305 # If a hook exists, give it a chance to interrupt
306 if test -x "$GIT_DIR/hooks/pre-rebase"
307 then
308         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
309                 echo >&2 "The pre-rebase hook refused to rebase."
310                 exit 1
311         }
312 fi
313
314 # If the branch to rebase is given, first switch to it.
315 case "$#" in
316 2)
317         branch_name="$2"
318         git-checkout "$2" || usage
319         ;;
320 *)
321         if branch_name=`git symbolic-ref -q HEAD`
322         then
323                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
324         else
325                 branch_name=HEAD ;# detached
326         fi
327         ;;
328 esac
329 branch=$(git rev-parse --verify "${branch_name}^0") || exit
330
331 # Now we are rebasing commits $upstream..$branch on top of $onto
332
333 # Check if we are already based on $onto with linear history,
334 # but this should be done only when upstream and onto are the same.
335 mb=$(git merge-base "$onto" "$branch")
336 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
337         # linear history?
338         ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
339 then
340         echo >&2 "Current branch $branch_name is up to date."
341         exit 0
342 fi
343
344 if test -n "$verbose"
345 then
346         echo "Changes from $mb to $onto:"
347         # We want color (if set), but no pager
348         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
349 fi
350
351 # move to a detached HEAD
352 orig_head=$(git rev-parse HEAD^0)
353 head_name=$(git symbolic-ref HEAD 2> /dev/null)
354 case "$head_name" in
355 '')
356         head_name="detached HEAD"
357         ;;
358 *)
359         git checkout "$orig_head" > /dev/null 2>&1 ||
360                 die "could not detach HEAD"
361         ;;
362 esac
363
364 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
365 echo "First, rewinding head to replay your work on top of it..."
366 git-reset --hard "$onto"
367
368 # If the $onto is a proper descendant of the tip of the branch, then
369 # we just fast forwarded.
370 if test "$mb" = "$branch"
371 then
372         echo >&2 "Fast-forwarded $branch_name to $onto_name."
373         move_to_original_branch
374         exit 0
375 fi
376
377 if test -z "$do_merge"
378 then
379         git format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
380         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG" &&
381         move_to_original_branch
382         ret=$?
383         test 0 != $ret -a -d .dotest &&
384                 echo $head_name > .dotest/head-name &&
385                 echo $onto > .dotest/onto &&
386                 echo $orig_head > .dotest/orig-head
387         exit $ret
388 fi
389
390 # start doing a rebase with git-merge
391 # this is rename-aware if the recursive (default) strategy is used
392
393 mkdir -p "$dotest"
394 echo "$onto" > "$dotest/onto"
395 echo "$onto_name" > "$dotest/onto_name"
396 prev_head=$orig_head
397 echo "$prev_head" > "$dotest/prev_head"
398 echo "$orig_head" > "$dotest/orig-head"
399 echo "$head_name" > "$dotest/head-name"
400
401 msgnum=0
402 for cmt in `git rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
403 do
404         msgnum=$(($msgnum + 1))
405         echo "$cmt" > "$dotest/cmt.$msgnum"
406 done
407
408 echo 1 >"$dotest/msgnum"
409 echo $msgnum >"$dotest/end"
410
411 end=$msgnum
412 msgnum=1
413
414 while test "$msgnum" -le "$end"
415 do
416         call_merge "$msgnum"
417         continue_merge
418 done
419
420 finish_rb_merge