Revert 88494423 (removal of duplicate parents in the output codepath)
[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         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_$hd
101                 return
102                 ;;
103         1)
104                 git rerere
105                 die "$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 case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
126         do
127                 shift
128         done && test -n "$1"
129 }
130
131 is_interactive "$@" && exec git-rebase--interactive "$@"
132
133 while case "$#" in 0) break ;; esac
134 do
135         case "$1" in
136         --continue)
137                 git diff-files --quiet || {
138                         echo "You must edit all merge conflicts and then"
139                         echo "mark them as resolved using git add"
140                         exit 1
141                 }
142                 if test -d "$dotest"
143                 then
144                         prev_head="`cat $dotest/prev_head`"
145                         end="`cat $dotest/end`"
146                         msgnum="`cat $dotest/msgnum`"
147                         onto="`cat $dotest/onto`"
148                         continue_merge
149                         while test "$msgnum" -le "$end"
150                         do
151                                 call_merge "$msgnum"
152                                 continue_merge
153                         done
154                         finish_rb_merge
155                         exit
156                 fi
157                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
158                 exit
159                 ;;
160         --skip)
161                 if test -d "$dotest"
162                 then
163                         git rerere clear
164                         prev_head="`cat $dotest/prev_head`"
165                         end="`cat $dotest/end`"
166                         msgnum="`cat $dotest/msgnum`"
167                         msgnum=$(($msgnum + 1))
168                         onto="`cat $dotest/onto`"
169                         while test "$msgnum" -le "$end"
170                         do
171                                 call_merge "$msgnum"
172                                 continue_merge
173                         done
174                         finish_rb_merge
175                         exit
176                 fi
177                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
178                 exit
179                 ;;
180         --abort)
181                 git rerere clear
182                 if test -d "$dotest"
183                 then
184                         rm -r "$dotest"
185                 elif test -d .dotest
186                 then
187                         rm -r .dotest
188                 else
189                         die "No rebase in progress?"
190                 fi
191                 git reset --hard ORIG_HEAD
192                 exit
193                 ;;
194         --onto)
195                 test 2 -le "$#" || usage
196                 newbase="$2"
197                 shift
198                 ;;
199         -M|-m|--m|--me|--mer|--merg|--merge)
200                 do_merge=t
201                 ;;
202         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
203                 --strateg=*|--strategy=*|\
204         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
205                 case "$#,$1" in
206                 *,*=*)
207                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
208                 1,*)
209                         usage ;;
210                 *)
211                         strategy="$2"
212                         shift ;;
213                 esac
214                 do_merge=t
215                 ;;
216         -v|--verbose)
217                 verbose=t
218                 ;;
219         -C*)
220                 git_am_opt=$1
221                 shift
222                 ;;
223         -*)
224                 usage
225                 ;;
226         *)
227                 break
228                 ;;
229         esac
230         shift
231 done
232
233 # Make sure we do not have .dotest
234 if test -z "$do_merge"
235 then
236         if mkdir .dotest
237         then
238                 rmdir .dotest
239         else
240                 echo >&2 '
241 It seems that I cannot create a .dotest directory, and I wonder if you
242 are in the middle of patch application or another rebase.  If that is not
243 the case, please rm -fr .dotest and run me again.  I am stopping in case
244 you still have something valuable there.'
245                 exit 1
246         fi
247 else
248         if test -d "$dotest"
249         then
250                 die "previous dotest directory $dotest still exists." \
251                         'try git-rebase < --continue | --abort >'
252         fi
253 fi
254
255 # The tree must be really really clean.
256 git update-index --refresh || exit
257 diff=$(git diff-index --cached --name-status -r HEAD)
258 case "$diff" in
259 ?*)     echo "cannot rebase: your index is not up-to-date"
260         echo "$diff"
261         exit 1
262         ;;
263 esac
264
265 # The upstream head must be given.  Make sure it is valid.
266 upstream_name="$1"
267 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
268     die "invalid upstream $upstream_name"
269
270 # Make sure the branch to rebase onto is valid.
271 onto_name=${newbase-"$upstream_name"}
272 onto=$(git rev-parse --verify "${onto_name}^0") || exit
273
274 # If a hook exists, give it a chance to interrupt
275 if test -x "$GIT_DIR/hooks/pre-rebase"
276 then
277         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
278                 echo >&2 "The pre-rebase hook refused to rebase."
279                 exit 1
280         }
281 fi
282
283 # If the branch to rebase is given, first switch to it.
284 case "$#" in
285 2)
286         branch_name="$2"
287         git-checkout "$2" || usage
288         ;;
289 *)
290         if branch_name=`git symbolic-ref -q HEAD`
291         then
292                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
293         else
294                 branch_name=HEAD ;# detached
295         fi
296         ;;
297 esac
298 branch=$(git rev-parse --verify "${branch_name}^0") || exit
299
300 # Now we are rebasing commits $upstream..$branch on top of $onto
301
302 # Check if we are already based on $onto with linear history,
303 # but this should be done only when upstream and onto are the same.
304 mb=$(git merge-base "$onto" "$branch")
305 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
306         # linear history?
307         ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
308 then
309         echo >&2 "Current branch $branch_name is up to date."
310         exit 0
311 fi
312
313 if test -n "$verbose"
314 then
315         echo "Changes from $mb to $onto:"
316         # We want color (if set), but no pager
317         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
318 fi
319
320 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
321 echo "First, rewinding head to replay your work on top of it..."
322 git-reset --hard "$onto"
323
324 # If the $onto is a proper descendant of the tip of the branch, then
325 # we just fast forwarded.
326 if test "$mb" = "$branch"
327 then
328         echo >&2 "Fast-forwarded $branch_name to $onto_name."
329         exit 0
330 fi
331
332 if test -z "$do_merge"
333 then
334         git format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
335         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG"
336         exit $?
337 fi
338
339 # start doing a rebase with git-merge
340 # this is rename-aware if the recursive (default) strategy is used
341
342 mkdir -p "$dotest"
343 echo "$onto" > "$dotest/onto"
344 echo "$onto_name" > "$dotest/onto_name"
345 prev_head=`git rev-parse HEAD^0`
346 echo "$prev_head" > "$dotest/prev_head"
347
348 msgnum=0
349 for cmt in `git rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
350 do
351         msgnum=$(($msgnum + 1))
352         echo "$cmt" > "$dotest/cmt.$msgnum"
353 done
354
355 echo 1 >"$dotest/msgnum"
356 echo $msgnum >"$dotest/end"
357
358 end=$msgnum
359 msgnum=1
360
361 while test "$msgnum" -le "$end"
362 do
363         call_merge "$msgnum"
364         continue_merge
365 done
366
367 finish_rb_merge