GIT v1.5.1.4
[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
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 update-index?"
59                 die "$RESOLVEMSG"
60         fi
61
62         if ! git-diff-index --quiet 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" $msgnum
73         fi
74         echo ' '`git-rev-list --pretty=oneline -1 HEAD | \
75                                 sed 's/^[a-f0-9]\+ //'`
76
77         prev_head=`git-rev-parse HEAD^0`
78         # save the resulting commit so we can read-tree on it later
79         echo "$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_$hd
101                 return
102                 ;;
103         1)
104                 test -d "$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 $cmt"
114                 ;;
115         esac
116 }
117
118 finish_rb_merge () {
119         rm -r "$dotest"
120         echo "All done."
121 }
122
123 while case "$#" in 0) break ;; esac
124 do
125         case "$1" in
126         --continue)
127                 git-diff-files --quiet || {
128                         echo "You must edit all merge conflicts and then"
129                         echo "mark them as resolved using git update-index"
130                         exit 1
131                 }
132                 if test -d "$dotest"
133                 then
134                         prev_head="`cat $dotest/prev_head`"
135                         end="`cat $dotest/end`"
136                         msgnum="`cat $dotest/msgnum`"
137                         onto="`cat $dotest/onto`"
138                         continue_merge
139                         while test "$msgnum" -le "$end"
140                         do
141                                 call_merge "$msgnum"
142                                 continue_merge
143                         done
144                         finish_rb_merge
145                         exit
146                 fi
147                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
148                 exit
149                 ;;
150         --skip)
151                 if test -d "$dotest"
152                 then
153                         if test -d "$GIT_DIR/rr-cache"
154                         then
155                                 git-rerere clear
156                         fi
157                         prev_head="`cat $dotest/prev_head`"
158                         end="`cat $dotest/end`"
159                         msgnum="`cat $dotest/msgnum`"
160                         msgnum=$(($msgnum + 1))
161                         onto="`cat $dotest/onto`"
162                         while test "$msgnum" -le "$end"
163                         do
164                                 call_merge "$msgnum"
165                                 continue_merge
166                         done
167                         finish_rb_merge
168                         exit
169                 fi
170                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
171                 exit
172                 ;;
173         --abort)
174                 if test -d "$GIT_DIR/rr-cache"
175                 then
176                         git-rerere clear
177                 fi
178                 if test -d "$dotest"
179                 then
180                         rm -r "$dotest"
181                 elif test -d .dotest
182                 then
183                         rm -r .dotest
184                 else
185                         die "No rebase in progress?"
186                 fi
187                 git reset --hard ORIG_HEAD
188                 exit
189                 ;;
190         --onto)
191                 test 2 -le "$#" || usage
192                 newbase="$2"
193                 shift
194                 ;;
195         -M|-m|--m|--me|--mer|--merg|--merge)
196                 do_merge=t
197                 ;;
198         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
199                 --strateg=*|--strategy=*|\
200         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
201                 case "$#,$1" in
202                 *,*=*)
203                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
204                 1,*)
205                         usage ;;
206                 *)
207                         strategy="$2"
208                         shift ;;
209                 esac
210                 do_merge=t
211                 ;;
212         -v|--verbose)
213                 verbose=t
214                 ;;
215         -C*)
216                 git_am_opt=$1
217                 shift
218                 ;;
219         -*)
220                 usage
221                 ;;
222         *)
223                 break
224                 ;;
225         esac
226         shift
227 done
228
229 # Make sure we do not have .dotest
230 if test -z "$do_merge"
231 then
232         if mkdir .dotest
233         then
234                 rmdir .dotest
235         else
236                 echo >&2 '
237 It seems that I cannot create a .dotest directory, and I wonder if you
238 are in the middle of patch application or another rebase.  If that is not
239 the case, please rm -fr .dotest and run me again.  I am stopping in case
240 you still have something valuable there.'
241                 exit 1
242         fi
243 else
244         if test -d "$dotest"
245         then
246                 die "previous dotest directory $dotest still exists." \
247                         'try git-rebase < --continue | --abort >'
248         fi
249 fi
250
251 # The tree must be really really clean.
252 git-update-index --refresh || exit
253 diff=$(git-diff-index --cached --name-status -r HEAD)
254 case "$diff" in
255 ?*)     echo "cannot rebase: your index is not up-to-date"
256         echo "$diff"
257         exit 1
258         ;;
259 esac
260
261 # The upstream head must be given.  Make sure it is valid.
262 upstream_name="$1"
263 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
264     die "invalid upstream $upstream_name"
265
266 # Make sure the branch to rebase onto is valid.
267 onto_name=${newbase-"$upstream_name"}
268 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
269
270 # If a hook exists, give it a chance to interrupt
271 if test -x "$GIT_DIR/hooks/pre-rebase"
272 then
273         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
274                 echo >&2 "The pre-rebase hook refused to rebase."
275                 exit 1
276         }
277 fi
278
279 # If the branch to rebase is given, first switch to it.
280 case "$#" in
281 2)
282         branch_name="$2"
283         git-checkout "$2" || usage
284         ;;
285 *)
286         if branch_name=`git symbolic-ref -q HEAD`
287         then
288                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
289         else
290                 branch_name=HEAD ;# detached
291         fi
292         ;;
293 esac
294 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
295
296 # Now we are rebasing commits $upstream..$branch on top of $onto
297
298 # Check if we are already based on $onto, but this should be
299 # done only when upstream and onto are the same.
300 mb=$(git-merge-base "$onto" "$branch")
301 if test "$upstream" = "$onto" && test "$mb" = "$onto"
302 then
303         echo >&2 "Current branch $branch_name is up to date."
304         exit 0
305 fi
306
307 if test -n "$verbose"
308 then
309         echo "Changes from $mb to $onto:"
310         git-diff-tree --stat --summary "$mb" "$onto"
311 fi
312
313 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
314 echo "First, rewinding head to replay your work on top of it..."
315 git-reset --hard "$onto"
316
317 # If the $onto is a proper descendant of the tip of the branch, then
318 # we just fast forwarded.
319 if test "$mb" = "$branch"
320 then
321         echo >&2 "Fast-forwarded $branch_name to $onto_name."
322         exit 0
323 fi
324
325 if test -z "$do_merge"
326 then
327         git-format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
328         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG"
329         exit $?
330 fi
331
332 # start doing a rebase with git-merge
333 # this is rename-aware if the recursive (default) strategy is used
334
335 mkdir -p "$dotest"
336 echo "$onto" > "$dotest/onto"
337 echo "$onto_name" > "$dotest/onto_name"
338 prev_head=`git-rev-parse HEAD^0`
339 echo "$prev_head" > "$dotest/prev_head"
340
341 msgnum=0
342 for cmt in `git-rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
343 do
344         msgnum=$(($msgnum + 1))
345         echo "$cmt" > "$dotest/cmt.$msgnum"
346 done
347
348 echo 1 >"$dotest/msgnum"
349 echo $msgnum >"$dotest/end"
350
351 end=$msgnum
352 msgnum=1
353
354 while test "$msgnum" -le "$end"
355 do
356         call_merge "$msgnum"
357         continue_merge
358 done
359
360 finish_rb_merge