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