Documentation: rename "hooks.txt" to "githooks.txt" and make it a man page
[git/dscho.git] / git-rebase.sh
blob9b13b833cb5762542848ee3e85e23d3ca0f76fa6
1 #!/bin/sh
3 # Copyright (c) 2005 Junio C Hamano.
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.
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.
23 Example:       git-rebase master~1 topic
25         A---B---C topic                   A'\''--B'\''--C'\'' topic
26        /                   -->           /
27   D---E---F---G master          D---E---F---G master
30 SUBDIRECTORY_OK=Yes
31 OPTIONS_SPEC=
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 to use git add?"
59                 die "$RESOLVEMSG"
60         fi
62         cmt=`cat "$dotest/current"`
63         if ! git diff-index --quiet HEAD --
64         then
65                 if ! git commit --no-verify -C "$cmt"
66                 then
67                         echo "Commit failed, please do not call \"git commit\""
68                         echo "directly, but instead do one of the following: "
69                         die "$RESOLVEMSG"
70                 fi
71                 printf "Committed: %0${prec}d " $msgnum
72         else
73                 printf "Already applied: %0${prec}d " $msgnum
74         fi
75         git rev-list --pretty=oneline -1 "$cmt" | sed -e 's/^[^ ]* //'
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=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
91         msgnum=$(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 $cmt"
114                 ;;
115         esac
118 move_to_original_branch () {
119         test -z "$head_name" &&
120                 head_name="$(cat "$dotest"/head-name)" &&
121                 onto="$(cat "$dotest"/onto)" &&
122                 orig_head="$(cat "$dotest"/orig-head)"
123         case "$head_name" in
124         refs/*)
125                 message="rebase finished: $head_name onto $onto"
126                 git update-ref -m "$message" \
127                         $head_name $(git rev-parse HEAD) $orig_head &&
128                 git symbolic-ref HEAD $head_name ||
129                 die "Could not move back to $head_name"
130                 ;;
131         esac
134 finish_rb_merge () {
135         move_to_original_branch
136         rm -r "$dotest"
137         echo "All done."
140 is_interactive () {
141         test -f "$dotest"/interactive ||
142         while :; do case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
143                 shift
144         done && test -n "$1"
147 is_interactive "$@" && exec git-rebase--interactive "$@"
149 while test $# != 0
151         case "$1" in
152         --continue)
153                 git diff-files --quiet || {
154                         echo "You must edit all merge conflicts and then"
155                         echo "mark them as resolved using git add"
156                         exit 1
157                 }
158                 if test -d "$dotest"
159                 then
160                         prev_head=$(cat "$dotest/prev_head")
161                         end=$(cat "$dotest/end")
162                         msgnum=$(cat "$dotest/msgnum")
163                         onto=$(cat "$dotest/onto")
164                         continue_merge
165                         while test "$msgnum" -le "$end"
166                         do
167                                 call_merge "$msgnum"
168                                 continue_merge
169                         done
170                         finish_rb_merge
171                         exit
172                 fi
173                 head_name=$(cat .dotest/head-name) &&
174                 onto=$(cat .dotest/onto) &&
175                 orig_head=$(cat .dotest/orig-head) &&
176                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
177                 move_to_original_branch
178                 exit
179                 ;;
180         --skip)
181                 git reset --hard HEAD || exit $?
182                 if test -d "$dotest"
183                 then
184                         git rerere clear
185                         prev_head=$(cat "$dotest/prev_head")
186                         end=$(cat "$dotest/end")
187                         msgnum=$(cat "$dotest/msgnum")
188                         msgnum=$(($msgnum + 1))
189                         onto=$(cat "$dotest/onto")
190                         while test "$msgnum" -le "$end"
191                         do
192                                 call_merge "$msgnum"
193                                 continue_merge
194                         done
195                         finish_rb_merge
196                         exit
197                 fi
198                 head_name=$(cat .dotest/head-name) &&
199                 onto=$(cat .dotest/onto) &&
200                 orig_head=$(cat .dotest/orig-head) &&
201                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
202                 move_to_original_branch
203                 exit
204                 ;;
205         --abort)
206                 git rerere clear
207                 if test -d "$dotest"
208                 then
209                         move_to_original_branch
210                 elif test -d .dotest
211                 then
212                         dotest=.dotest
213                         move_to_original_branch
214                 else
215                         die "No rebase in progress?"
216                 fi
217                 git reset --hard $(cat $dotest/orig-head)
218                 rm -r "$dotest"
219                 exit
220                 ;;
221         --onto)
222                 test 2 -le "$#" || usage
223                 newbase="$2"
224                 shift
225                 ;;
226         -M|-m|--m|--me|--mer|--merg|--merge)
227                 do_merge=t
228                 ;;
229         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
230                 --strateg=*|--strategy=*|\
231         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
232                 case "$#,$1" in
233                 *,*=*)
234                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
235                 1,*)
236                         usage ;;
237                 *)
238                         strategy="$2"
239                         shift ;;
240                 esac
241                 do_merge=t
242                 ;;
243         -v|--verbose)
244                 verbose=t
245                 ;;
246         --whitespace=*)
247                 git_am_opt="$git_am_opt $1"
248                 ;;
249         -C*)
250                 git_am_opt="$git_am_opt $1"
251                 ;;
252         -*)
253                 usage
254                 ;;
255         *)
256                 break
257                 ;;
258         esac
259         shift
260 done
262 # Make sure we do not have .dotest
263 if test -z "$do_merge"
264 then
265         if mkdir .dotest
266         then
267                 rmdir .dotest
268         else
269                 echo >&2 '
270 It seems that I cannot create a .dotest directory, and I wonder if you
271 are in the middle of patch application or another rebase.  If that is not
272 the case, please rm -fr .dotest and run me again.  I am stopping in case
273 you still have something valuable there.'
274                 exit 1
275         fi
276 else
277         if test -d "$dotest"
278         then
279                 die "previous dotest directory $dotest still exists." \
280                         'try git-rebase < --continue | --abort >'
281         fi
284 # The tree must be really really clean.
285 git update-index --refresh || exit
286 diff=$(git diff-index --cached --name-status -r HEAD --)
287 case "$diff" in
288 ?*)     echo "cannot rebase: your index is not up-to-date"
289         echo "$diff"
290         exit 1
291         ;;
292 esac
294 # The upstream head must be given.  Make sure it is valid.
295 upstream_name="$1"
296 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
297     die "invalid upstream $upstream_name"
299 # Make sure the branch to rebase onto is valid.
300 onto_name=${newbase-"$upstream_name"}
301 onto=$(git rev-parse --verify "${onto_name}^0") || exit
303 # If a hook exists, give it a chance to interrupt
304 if test -x "$GIT_DIR/hooks/pre-rebase"
305 then
306         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
307                 echo >&2 "The pre-rebase hook refused to rebase."
308                 exit 1
309         }
312 # If the branch to rebase is given, that is the branch we will rebase
313 # $branch_name -- branch being rebased, or HEAD (already detached)
314 # $orig_head -- commit object name of tip of the branch before rebasing
315 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
316 switch_to=
317 case "$#" in
319         # Is it "rebase other $branchname" or "rebase other $commit"?
320         branch_name="$2"
321         switch_to="$2"
323         if git show-ref --verify --quiet -- "refs/heads/$2" &&
324            branch=$(git rev-parse --verify "refs/heads/$2" 2>/dev/null)
325         then
326                 head_name="refs/heads/$2"
327         elif branch=$(git rev-parse --verify "$2" 2>/dev/null)
328         then
329                 head_name="detached HEAD"
330         else
331                 usage
332         fi
333         ;;
335         # Do not need to switch branches, we are already on it.
336         if branch_name=`git symbolic-ref -q HEAD`
337         then
338                 head_name=$branch_name
339                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
340         else
341                 head_name="detached HEAD"
342                 branch_name=HEAD ;# detached
343         fi
344         branch=$(git rev-parse --verify "${branch_name}^0") || exit
345         ;;
346 esac
347 orig_head=$branch
349 # Now we are rebasing commits $upstream..$branch on top of $onto
351 # Check if we are already based on $onto with linear history,
352 # but this should be done only when upstream and onto are the same.
353 mb=$(git merge-base "$onto" "$branch")
354 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
355         # linear history?
356         ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
357 then
358         # Lazily switch to the target branch if needed...
359         test -z "$switch_to" || git checkout "$switch_to"
360         echo >&2 "Current branch $branch_name is up to date."
361         exit 0
364 if test -n "$verbose"
365 then
366         echo "Changes from $mb to $onto:"
367         # We want color (if set), but no pager
368         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
371 # Detach HEAD and reset the tree
372 echo "First, rewinding head to replay your work on top of it..."
373 git checkout "$onto^0" >/dev/null 2>&1 ||
374         die "could not detach HEAD"
375 # git reset --hard "$onto^0"
377 # If the $onto is a proper descendant of the tip of the branch, then
378 # we just fast forwarded.
379 if test "$mb" = "$branch"
380 then
381         echo >&2 "Fast-forwarded $branch_name to $onto_name."
382         move_to_original_branch
383         exit 0
386 if test -z "$do_merge"
387 then
388         git format-patch -k --stdout --full-index --ignore-if-in-upstream \
389                 "$upstream..$orig_head" |
390         git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
391         move_to_original_branch
392         ret=$?
393         test 0 != $ret -a -d .dotest &&
394                 echo $head_name > .dotest/head-name &&
395                 echo $onto > .dotest/onto &&
396                 echo $orig_head > .dotest/orig-head
397         exit $ret
400 # start doing a rebase with git-merge
401 # this is rename-aware if the recursive (default) strategy is used
403 mkdir -p "$dotest"
404 echo "$onto" > "$dotest/onto"
405 echo "$onto_name" > "$dotest/onto_name"
406 prev_head=$orig_head
407 echo "$prev_head" > "$dotest/prev_head"
408 echo "$orig_head" > "$dotest/orig-head"
409 echo "$head_name" > "$dotest/head-name"
411 msgnum=0
412 for cmt in `git rev-list --reverse --no-merges "$upstream..$orig_head"`
414         msgnum=$(($msgnum + 1))
415         echo "$cmt" > "$dotest/cmt.$msgnum"
416 done
418 echo 1 >"$dotest/msgnum"
419 echo $msgnum >"$dotest/end"
421 end=$msgnum
422 msgnum=1
424 while test "$msgnum" -le "$end"
426         call_merge "$msgnum"
427         continue_merge
428 done
430 finish_rb_merge