Don't create a final empty packfile in fast-import.
[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 set_reflog_action rebase
32 require_work_tree
33
34 RESOLVEMSG="
35 When you have resolved this problem run \"git rebase --continue\".
36 If you would prefer to skip this patch, instead run \"git rebase --skip\".
37 To restore the original branch and stop rebasing run \"git rebase --abort\".
38 "
39 unset newbase
40 strategy=recursive
41 do_merge=
42 dotest=$GIT_DIR/.dotest-merge
43 prec=4
44 verbose=
45
46 continue_merge () {
47         test -n "$prev_head" || die "prev_head must be defined"
48         test -d "$dotest" || die "$dotest directory does not exist"
49
50         unmerged=$(git-ls-files -u)
51         if test -n "$unmerged"
52         then
53                 echo "You still have unmerged paths in your index"
54                 echo "did you forget update-index?"
55                 die "$RESOLVEMSG"
56         fi
57
58         if test -n "`git-diff-index HEAD`"
59         then
60                 if ! git-commit -C "`cat $dotest/current`"
61                 then
62                         echo "Commit failed, please do not call \"git commit\""
63                         echo "directly, but instead do one of the following: "
64                         die "$RESOLVEMSG"
65                 fi
66                 printf "Committed: %0${prec}d" $msgnum
67         else
68                 printf "Already applied: %0${prec}d" $msgnum
69         fi
70         echo ' '`git-rev-list --pretty=oneline -1 HEAD | \
71                                 sed 's/^[a-f0-9]\+ //'`
72
73         prev_head=`git-rev-parse HEAD^0`
74         # save the resulting commit so we can read-tree on it later
75         echo "$prev_head" > "$dotest/prev_head"
76
77         # onto the next patch:
78         msgnum=$(($msgnum + 1))
79         echo "$msgnum" >"$dotest/msgnum"
80 }
81
82 call_merge () {
83         cmt="$(cat $dotest/cmt.$1)"
84         echo "$cmt" > "$dotest/current"
85         hd=$(git-rev-parse --verify HEAD)
86         cmt_name=$(git-symbolic-ref HEAD)
87         msgnum=$(cat $dotest/msgnum)
88         end=$(cat $dotest/end)
89         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
90         eval GITHEAD_$hd='"$(cat $dotest/onto_name)"'
91         export GITHEAD_$cmt GITHEAD_$hd
92         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
93         rv=$?
94         case "$rv" in
95         0)
96                 unset GITHEAD_$cmt GITHEAD_$hd
97                 return
98                 ;;
99         1)
100                 test -d "$GIT_DIR/rr-cache" && git-rerere
101                 die "$RESOLVEMSG"
102                 ;;
103         2)
104                 echo "Strategy: $rv $strategy failed, try another" 1>&2
105                 die "$RESOLVEMSG"
106                 ;;
107         *)
108                 die "Unknown exit code ($rv) from command:" \
109                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
110                 ;;
111         esac
112 }
113
114 finish_rb_merge () {
115         rm -r "$dotest"
116         echo "All done."
117 }
118
119 while case "$#" in 0) break ;; esac
120 do
121         case "$1" in
122         --continue)
123                 diff=$(git-diff-files)
124                 case "$diff" in
125                 ?*)     echo "You must edit all merge conflicts and then"
126                         echo "mark them as resolved using git update-index"
127                         exit 1
128                         ;;
129                 esac
130                 if test -d "$dotest"
131                 then
132                         prev_head="`cat $dotest/prev_head`"
133                         end="`cat $dotest/end`"
134                         msgnum="`cat $dotest/msgnum`"
135                         onto="`cat $dotest/onto`"
136                         continue_merge
137                         while test "$msgnum" -le "$end"
138                         do
139                                 call_merge "$msgnum"
140                                 continue_merge
141                         done
142                         finish_rb_merge
143                         exit
144                 fi
145                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
146                 exit
147                 ;;
148         --skip)
149                 if test -d "$dotest"
150                 then
151                         if test -d "$GIT_DIR/rr-cache"
152                         then
153                                 git-rerere clear
154                         fi
155                         prev_head="`cat $dotest/prev_head`"
156                         end="`cat $dotest/end`"
157                         msgnum="`cat $dotest/msgnum`"
158                         msgnum=$(($msgnum + 1))
159                         onto="`cat $dotest/onto`"
160                         while test "$msgnum" -le "$end"
161                         do
162                                 call_merge "$msgnum"
163                                 continue_merge
164                         done
165                         finish_rb_merge
166                         exit
167                 fi
168                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
169                 exit
170                 ;;
171         --abort)
172                 if test -d "$GIT_DIR/rr-cache"
173                 then
174                         git-rerere clear
175                 fi
176                 if test -d "$dotest"
177                 then
178                         rm -r "$dotest"
179                 elif test -d .dotest
180                 then
181                         rm -r .dotest
182                 else
183                         die "No rebase in progress?"
184                 fi
185                 git reset --hard ORIG_HEAD
186                 exit
187                 ;;
188         --onto)
189                 test 2 -le "$#" || usage
190                 newbase="$2"
191                 shift
192                 ;;
193         -M|-m|--m|--me|--mer|--merg|--merge)
194                 do_merge=t
195                 ;;
196         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
197                 --strateg=*|--strategy=*|\
198         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
199                 case "$#,$1" in
200                 *,*=*)
201                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
202                 1,*)
203                         usage ;;
204                 *)
205                         strategy="$2"
206                         shift ;;
207                 esac
208                 do_merge=t
209                 ;;
210         -v|--verbose)
211                 verbose=t
212                 ;;
213         -*)
214                 usage
215                 ;;
216         *)
217                 break
218                 ;;
219         esac
220         shift
221 done
222
223 # Make sure we do not have .dotest
224 if test -z "$do_merge"
225 then
226         if mkdir .dotest
227         then
228                 rmdir .dotest
229         else
230                 echo >&2 '
231 It seems that I cannot create a .dotest directory, and I wonder if you
232 are in the middle of patch application or another rebase.  If that is not
233 the case, please rm -fr .dotest and run me again.  I am stopping in case
234 you still have something valuable there.'
235                 exit 1
236         fi
237 else
238         if test -d "$dotest"
239         then
240                 die "previous dotest directory $dotest still exists." \
241                         'try git-rebase < --continue | --abort >'
242         fi
243 fi
244
245 # The tree must be really really clean.
246 git-update-index --refresh || exit
247 diff=$(git-diff-index --cached --name-status -r HEAD)
248 case "$diff" in
249 ?*)     echo "$diff"
250         exit 1
251         ;;
252 esac
253
254 # The upstream head must be given.  Make sure it is valid.
255 upstream_name="$1"
256 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
257     die "invalid upstream $upstream_name"
258
259 # If a hook exists, give it a chance to interrupt
260 if test -x "$GIT_DIR/hooks/pre-rebase"
261 then
262         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
263                 echo >&2 "The pre-rebase hook refused to rebase."
264                 exit 1
265         }
266 fi
267
268 # If the branch to rebase is given, first switch to it.
269 case "$#" in
270 2)
271         branch_name="$2"
272         git-checkout "$2" || usage
273         ;;
274 *)
275         branch_name=`git symbolic-ref HEAD` || die "No current branch"
276         branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
277         ;;
278 esac
279 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
280
281 # Make sure the branch to rebase onto is valid.
282 onto_name=${newbase-"$upstream_name"}
283 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
284
285 # Now we are rebasing commits $upstream..$branch on top of $onto
286
287 # Check if we are already based on $onto, but this should be
288 # done only when upstream and onto are the same.
289 mb=$(git-merge-base "$onto" "$branch")
290 if test "$upstream" = "$onto" && test "$mb" = "$onto"
291 then
292         echo >&2 "Current branch $branch_name is up to date."
293         exit 0
294 fi
295
296 if test -n "$verbose"
297 then
298         echo "Changes from $mb to $onto:"
299         git-diff-tree --stat --summary "$mb" "$onto"
300 fi
301
302 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
303 echo "First, rewinding head to replay your work on top of it..."
304 git-reset --hard "$onto"
305
306 # If the $onto is a proper descendant of the tip of the branch, then
307 # we just fast forwarded.
308 if test "$mb" = "$branch"
309 then
310         echo >&2 "Fast-forwarded $branch_name to $onto_name."
311         exit 0
312 fi
313
314 if test -z "$do_merge"
315 then
316         git-format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
317         git am --binary -3 -k --resolvemsg="$RESOLVEMSG"
318         exit $?
319 fi
320
321 # start doing a rebase with git-merge
322 # this is rename-aware if the recursive (default) strategy is used
323
324 mkdir -p "$dotest"
325 echo "$onto" > "$dotest/onto"
326 echo "$onto_name" > "$dotest/onto_name"
327 prev_head=`git-rev-parse HEAD^0`
328 echo "$prev_head" > "$dotest/prev_head"
329
330 msgnum=0
331 for cmt in `git-rev-list --no-merges "$upstream"..ORIG_HEAD \
332                         | @@PERL@@ -e 'print reverse <>'`
333 do
334         msgnum=$(($msgnum + 1))
335         echo "$cmt" > "$dotest/cmt.$msgnum"
336 done
337
338 echo 1 >"$dotest/msgnum"
339 echo $msgnum >"$dotest/end"
340
341 end=$msgnum
342 msgnum=1
343
344 while test "$msgnum" -le "$end"
345 do
346         call_merge "$msgnum"
347         continue_merge
348 done
349
350 finish_rb_merge