Merge branch 'maint'
[git] / git-rebase.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano.
4 #
5
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.
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 . git-sh-setup
31
32 RESOLVEMSG="
33 When you have resolved this problem run \"git rebase --continue\".
34 If you would prefer to skip this patch, instead run \"git rebase --skip\".
35 To restore the original branch and stop rebasing run \"git rebase --abort\".
36 "
37 unset newbase
38 strategy=recursive
39 do_merge=
40 dotest=$GIT_DIR/.dotest-merge
41 prec=4
42 verbose=
43
44 continue_merge () {
45         test -n "$prev_head" || die "prev_head must be defined"
46         test -d "$dotest" || die "$dotest directory does not exist"
47
48         unmerged=$(git-ls-files -u)
49         if test -n "$unmerged"
50         then
51                 echo "You still have unmerged paths in your index"
52                 echo "did you forget update-index?"
53                 die "$RESOLVEMSG"
54         fi
55
56         if test -n "`git-diff-index HEAD`"
57         then
58                 if ! git-commit -C "`cat $dotest/current`"
59                 then
60                         echo "Commit failed, please do not call \"git commit\""
61                         echo "directly, but instead do one of the following: "
62                         die "$RESOLVEMSG"
63                 fi
64                 printf "Committed: %0${prec}d" $msgnum
65         else
66                 printf "Already applied: %0${prec}d" $msgnum
67         fi
68         echo ' '`git-rev-list --pretty=oneline -1 HEAD | \
69                                 sed 's/^[a-f0-9]\+ //'`
70
71         prev_head=`git-rev-parse HEAD^0`
72         # save the resulting commit so we can read-tree on it later
73         echo "$prev_head" > "$dotest/prev_head"
74
75         # onto the next patch:
76         msgnum=$(($msgnum + 1))
77         echo "$msgnum" >"$dotest/msgnum"
78 }
79
80 call_merge () {
81         cmt="$(cat $dotest/cmt.$1)"
82         echo "$cmt" > "$dotest/current"
83         git-merge-$strategy "$cmt^" -- HEAD "$cmt"
84         rv=$?
85         case "$rv" in
86         0)
87                 return
88                 ;;
89         1)
90                 test -d "$GIT_DIR/rr-cache" && git-rerere
91                 die "$RESOLVEMSG"
92                 ;;
93         2)
94                 echo "Strategy: $rv $strategy failed, try another" 1>&2
95                 die "$RESOLVEMSG"
96                 ;;
97         *)
98                 die "Unknown exit code ($rv) from command:" \
99                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
100                 ;;
101         esac
102 }
103
104 finish_rb_merge () {
105         rm -r "$dotest"
106         echo "All done."
107 }
108
109 while case "$#" in 0) break ;; esac
110 do
111         case "$1" in
112         --continue)
113                 diff=$(git-diff-files)
114                 case "$diff" in
115                 ?*)     echo "You must edit all merge conflicts and then"
116                         echo "mark them as resolved using git update-index"
117                         exit 1
118                         ;;
119                 esac
120                 if test -d "$dotest"
121                 then
122                         prev_head="`cat $dotest/prev_head`"
123                         end="`cat $dotest/end`"
124                         msgnum="`cat $dotest/msgnum`"
125                         onto="`cat $dotest/onto`"
126                         continue_merge
127                         while test "$msgnum" -le "$end"
128                         do
129                                 call_merge "$msgnum"
130                                 continue_merge
131                         done
132                         finish_rb_merge
133                         exit
134                 fi
135                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" \
136                         --reflog-action=rebase
137                 exit
138                 ;;
139         --skip)
140                 if test -d "$dotest"
141                 then
142                         if test -d "$GIT_DIR/rr-cache"
143                         then
144                                 git-rerere clear
145                         fi
146                         prev_head="`cat $dotest/prev_head`"
147                         end="`cat $dotest/end`"
148                         msgnum="`cat $dotest/msgnum`"
149                         msgnum=$(($msgnum + 1))
150                         onto="`cat $dotest/onto`"
151                         while test "$msgnum" -le "$end"
152                         do
153                                 call_merge "$msgnum"
154                                 continue_merge
155                         done
156                         finish_rb_merge
157                         exit
158                 fi
159                 git am -3 --skip --resolvemsg="$RESOLVEMSG" \
160                         --reflog-action=rebase
161                 exit
162                 ;;
163         --abort)
164                 if test -d "$GIT_DIR/rr-cache"
165                 then
166                         git-rerere clear
167                 fi
168                 if test -d "$dotest"
169                 then
170                         rm -r "$dotest"
171                 elif test -d .dotest
172                 then
173                         rm -r .dotest
174                 else
175                         die "No rebase in progress?"
176                 fi
177                 git reset --hard ORIG_HEAD
178                 exit
179                 ;;
180         --onto)
181                 test 2 -le "$#" || usage
182                 newbase="$2"
183                 shift
184                 ;;
185         -M|-m|--m|--me|--mer|--merg|--merge)
186                 do_merge=t
187                 ;;
188         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
189                 --strateg=*|--strategy=*|\
190         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
191                 case "$#,$1" in
192                 *,*=*)
193                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
194                 1,*)
195                         usage ;;
196                 *)
197                         strategy="$2"
198                         shift ;;
199                 esac
200                 do_merge=t
201                 ;;
202         -v|--verbose)
203                 verbose=t
204                 ;;
205         -*)
206                 usage
207                 ;;
208         *)
209                 break
210                 ;;
211         esac
212         shift
213 done
214
215 # Make sure we do not have .dotest
216 if test -z "$do_merge"
217 then
218         if mkdir .dotest
219         then
220                 rmdir .dotest
221         else
222                 echo >&2 '
223 It seems that I cannot create a .dotest directory, and I wonder if you
224 are in the middle of patch application or another rebase.  If that is not
225 the case, please rm -fr .dotest and run me again.  I am stopping in case
226 you still have something valuable there.'
227                 exit 1
228         fi
229 else
230         if test -d "$dotest"
231         then
232                 die "previous dotest directory $dotest still exists." \
233                         'try git-rebase < --continue | --abort >'
234         fi
235 fi
236
237 # The tree must be really really clean.
238 git-update-index --refresh || exit
239 diff=$(git-diff-index --cached --name-status -r HEAD)
240 case "$diff" in
241 ?*)     echo "$diff"
242         exit 1
243         ;;
244 esac
245
246 # The upstream head must be given.  Make sure it is valid.
247 upstream_name="$1"
248 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
249     die "invalid upstream $upstream_name"
250
251 # If a hook exists, give it a chance to interrupt
252 if test -x "$GIT_DIR/hooks/pre-rebase"
253 then
254         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
255                 echo >&2 "The pre-rebase hook refused to rebase."
256                 exit 1
257         }
258 fi
259
260 # If the branch to rebase is given, first switch to it.
261 case "$#" in
262 2)
263         branch_name="$2"
264         git-checkout "$2" || usage
265         ;;
266 *)
267         branch_name=`git symbolic-ref HEAD` || die "No current branch"
268         branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
269         ;;
270 esac
271 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
272
273 # Make sure the branch to rebase onto is valid.
274 onto_name=${newbase-"$upstream_name"}
275 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
276
277 # Now we are rebasing commits $upstream..$branch on top of $onto
278
279 # Check if we are already based on $onto, but this should be
280 # done only when upstream and onto are the same.
281 mb=$(git-merge-base "$onto" "$branch")
282 if test "$upstream" = "$onto" && test "$mb" = "$onto"
283 then
284         echo >&2 "Current branch $branch_name is up to date."
285         exit 0
286 fi
287
288 if test -n "$verbose"
289 then
290         echo "Changes from $mb to $onto:"
291         git-diff-tree --stat --summary "$mb" "$onto"
292 fi
293
294 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
295 git-reset --hard "$onto"
296
297 # If the $onto is a proper descendant of the tip of the branch, then
298 # we just fast forwarded.
299 if test "$mb" = "$branch"
300 then
301         echo >&2 "Fast-forwarded $branch_name to $onto_name."
302         exit 0
303 fi
304
305 if test -z "$do_merge"
306 then
307         git-format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
308         git am --binary -3 -k --resolvemsg="$RESOLVEMSG" \
309                 --reflog-action=rebase
310         exit $?
311 fi
312
313 # start doing a rebase with git-merge
314 # this is rename-aware if the recursive (default) strategy is used
315
316 mkdir -p "$dotest"
317 echo "$onto" > "$dotest/onto"
318 prev_head=`git-rev-parse HEAD^0`
319 echo "$prev_head" > "$dotest/prev_head"
320
321 msgnum=0
322 for cmt in `git-rev-list --no-merges "$upstream"..ORIG_HEAD \
323                         | @@PERL@@ -e 'print reverse <>'`
324 do
325         msgnum=$(($msgnum + 1))
326         echo "$cmt" > "$dotest/cmt.$msgnum"
327 done
328
329 echo 1 >"$dotest/msgnum"
330 echo $msgnum >"$dotest/end"
331
332 end=$msgnum
333 msgnum=1
334
335 while test "$msgnum" -le "$end"
336 do
337         call_merge "$msgnum"
338         continue_merge
339 done
340
341 finish_rb_merge