git-svn: fix some potential bugs with --follow-parent
[git/dscho.git] / git-rebase.sh
blobb51d19d12e6d5a108f13c4ec60c5f5a6e560ef47
1 #!/bin/sh
3 # Copyright (c) 2005 Junio C Hamano.
6 USAGE='[-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.
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.
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.
24 Example:       git-rebase master~1 topic
26         A---B---C topic                   A'\''--B'\''--C'\'' topic
27        /                   -->           /
28   D---E---F---G master          D---E---F---G master
31 SUBDIRECTORY_OK=Yes
32 . git-sh-setup
33 set_reflog_action rebase
34 require_work_tree
35 cd_to_toplevel
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\".
42 unset newbase
43 strategy=recursive
44 do_merge=
45 dotest=$GIT_DIR/.dotest-merge
46 prec=4
47 verbose=
48 git_am_opt=
50 continue_merge () {
51         test -n "$prev_head" || die "prev_head must be defined"
52         test -d "$dotest" || die "$dotest directory does not exist"
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 update-index?"
59                 die "$RESOLVEMSG"
60         fi
62         if test -n "`git-diff-index HEAD`"
63         then
64                 if ! git-commit -C "`cat $dotest/current`"
65                 then
66                         echo "Commit failed, please do not call \"git commit\""
67                         echo "directly, but instead do one of the following: "
68                         die "$RESOLVEMSG"
69                 fi
70                 printf "Committed: %0${prec}d" $msgnum
71         else
72                 printf "Already applied: %0${prec}d" $msgnum
73         fi
74         echo ' '`git-rev-list --pretty=oneline -1 HEAD | \
75                                 sed 's/^[a-f0-9]\+ //'`
77         prev_head=`git-rev-parse HEAD^0`
78         # save the resulting commit so we can read-tree on it later
79         echo "$prev_head" > "$dotest/prev_head"
81         # onto the next patch:
82         msgnum=$(($msgnum + 1))
83         echo "$msgnum" >"$dotest/msgnum"
86 call_merge () {
87         cmt="$(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_$hd
101                 return
102                 ;;
103         1)
104                 test -d "$GIT_DIR/rr-cache" && 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 $cmt"
114                 ;;
115         esac
118 finish_rb_merge () {
119         rm -r "$dotest"
120         echo "All done."
123 while case "$#" in 0) break ;; esac
125         case "$1" in
126         --continue)
127                 diff=$(git-diff-files)
128                 case "$diff" in
129                 ?*)     echo "You must edit all merge conflicts and then"
130                         echo "mark them as resolved using git update-index"
131                         exit 1
132                         ;;
133                 esac
134                 if test -d "$dotest"
135                 then
136                         prev_head="`cat $dotest/prev_head`"
137                         end="`cat $dotest/end`"
138                         msgnum="`cat $dotest/msgnum`"
139                         onto="`cat $dotest/onto`"
140                         continue_merge
141                         while test "$msgnum" -le "$end"
142                         do
143                                 call_merge "$msgnum"
144                                 continue_merge
145                         done
146                         finish_rb_merge
147                         exit
148                 fi
149                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
150                 exit
151                 ;;
152         --skip)
153                 if test -d "$dotest"
154                 then
155                         if test -d "$GIT_DIR/rr-cache"
156                         then
157                                 git-rerere clear
158                         fi
159                         prev_head="`cat $dotest/prev_head`"
160                         end="`cat $dotest/end`"
161                         msgnum="`cat $dotest/msgnum`"
162                         msgnum=$(($msgnum + 1))
163                         onto="`cat $dotest/onto`"
164                         while test "$msgnum" -le "$end"
165                         do
166                                 call_merge "$msgnum"
167                                 continue_merge
168                         done
169                         finish_rb_merge
170                         exit
171                 fi
172                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
173                 exit
174                 ;;
175         --abort)
176                 if test -d "$GIT_DIR/rr-cache"
177                 then
178                         git-rerere clear
179                 fi
180                 if test -d "$dotest"
181                 then
182                         rm -r "$dotest"
183                 elif test -d .dotest
184                 then
185                         rm -r .dotest
186                 else
187                         die "No rebase in progress?"
188                 fi
189                 git reset --hard ORIG_HEAD
190                 exit
191                 ;;
192         --onto)
193                 test 2 -le "$#" || usage
194                 newbase="$2"
195                 shift
196                 ;;
197         -M|-m|--m|--me|--mer|--merg|--merge)
198                 do_merge=t
199                 ;;
200         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
201                 --strateg=*|--strategy=*|\
202         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
203                 case "$#,$1" in
204                 *,*=*)
205                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
206                 1,*)
207                         usage ;;
208                 *)
209                         strategy="$2"
210                         shift ;;
211                 esac
212                 do_merge=t
213                 ;;
214         -v|--verbose)
215                 verbose=t
216                 ;;
217         -C*)
218                 git_am_opt=$1
219                 shift
220                 ;;
221         -*)
222                 usage
223                 ;;
224         *)
225                 break
226                 ;;
227         esac
228         shift
229 done
231 # Make sure we do not have .dotest
232 if test -z "$do_merge"
233 then
234         if mkdir .dotest
235         then
236                 rmdir .dotest
237         else
238                 echo >&2 '
239 It seems that I cannot create a .dotest directory, and I wonder if you
240 are in the middle of patch application or another rebase.  If that is not
241 the case, please rm -fr .dotest and run me again.  I am stopping in case
242 you still have something valuable there.'
243                 exit 1
244         fi
245 else
246         if test -d "$dotest"
247         then
248                 die "previous dotest directory $dotest still exists." \
249                         'try git-rebase < --continue | --abort >'
250         fi
253 # The tree must be really really clean.
254 git-update-index --refresh || exit
255 diff=$(git-diff-index --cached --name-status -r HEAD)
256 case "$diff" in
257 ?*)     echo "cannot rebase: your index is not up-to-date"
258         echo "$diff"
259         exit 1
260         ;;
261 esac
263 # The upstream head must be given.  Make sure it is valid.
264 upstream_name="$1"
265 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
266     die "invalid upstream $upstream_name"
268 # If a hook exists, give it a chance to interrupt
269 if test -x "$GIT_DIR/hooks/pre-rebase"
270 then
271         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
272                 echo >&2 "The pre-rebase hook refused to rebase."
273                 exit 1
274         }
277 # If the branch to rebase is given, first switch to it.
278 case "$#" in
280         branch_name="$2"
281         git-checkout "$2" || usage
282         ;;
284         if branch_name=`git symbolic-ref -q HEAD`
285         then
286                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
287         else
288                 branch_name=HEAD ;# detached
289         fi
290         ;;
291 esac
292 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
294 # Make sure the branch to rebase onto is valid.
295 onto_name=${newbase-"$upstream_name"}
296 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
298 # Now we are rebasing commits $upstream..$branch on top of $onto
300 # Check if we are already based on $onto, but this should be
301 # done only when upstream and onto are the same.
302 mb=$(git-merge-base "$onto" "$branch")
303 if test "$upstream" = "$onto" && test "$mb" = "$onto"
304 then
305         echo >&2 "Current branch $branch_name is up to date."
306         exit 0
309 if test -n "$verbose"
310 then
311         echo "Changes from $mb to $onto:"
312         git-diff-tree --stat --summary "$mb" "$onto"
315 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
316 echo "First, rewinding head to replay your work on top of it..."
317 git-reset --hard "$onto"
319 # If the $onto is a proper descendant of the tip of the branch, then
320 # we just fast forwarded.
321 if test "$mb" = "$branch"
322 then
323         echo >&2 "Fast-forwarded $branch_name to $onto_name."
324         exit 0
327 if test -z "$do_merge"
328 then
329         git-format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
330         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG"
331         exit $?
334 # start doing a rebase with git-merge
335 # this is rename-aware if the recursive (default) strategy is used
337 mkdir -p "$dotest"
338 echo "$onto" > "$dotest/onto"
339 echo "$onto_name" > "$dotest/onto_name"
340 prev_head=`git-rev-parse HEAD^0`
341 echo "$prev_head" > "$dotest/prev_head"
343 msgnum=0
344 for cmt in `git-rev-list --no-merges "$upstream"..ORIG_HEAD \
345                         | @@PERL@@ -e 'print reverse <>'`
347         msgnum=$(($msgnum + 1))
348         echo "$cmt" > "$dotest/cmt.$msgnum"
349 done
351 echo 1 >"$dotest/msgnum"
352 echo $msgnum >"$dotest/end"
354 end=$msgnum
355 msgnum=1
357 while test "$msgnum" -le "$end"
359         call_merge "$msgnum"
360         continue_merge
361 done
363 finish_rb_merge