Merge branch 'jf/am-failure-report'
[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>|--root] [<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 .git/rebase-apply working files, use the
18 command 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.
22
23 Example:       git-rebase master~1 topic
24
25         A---B---C topic                   A'\''--B'\''--C'\'' topic
26        /                   -->           /
27   D---E---F---G master          D---E---F---G master
28 '
29
30 SUBDIRECTORY_OK=Yes
31 OPTIONS_SPEC=
32 . git-sh-setup
33 set_reflog_action rebase
34 require_work_tree
35 cd_to_toplevel
36
37 OK_TO_SKIP_PRE_REBASE=
38 RESOLVEMSG="
39 When you have resolved this problem run \"git rebase --continue\".
40 If you would prefer to skip this patch, instead run \"git rebase --skip\".
41 To restore the original branch and stop rebasing run \"git rebase --abort\".
42 "
43 unset newbase
44 strategy=recursive
45 do_merge=
46 dotest="$GIT_DIR"/rebase-merge
47 prec=4
48 verbose=
49 git_am_opt=
50 rebase_root=
51
52 continue_merge () {
53         test -n "$prev_head" || die "prev_head must be defined"
54         test -d "$dotest" || die "$dotest directory does not exist"
55
56         unmerged=$(git ls-files -u)
57         if test -n "$unmerged"
58         then
59                 echo "You still have unmerged paths in your index"
60                 echo "did you forget to use git add?"
61                 die "$RESOLVEMSG"
62         fi
63
64         cmt=`cat "$dotest/current"`
65         if ! git diff-index --quiet --ignore-submodules HEAD --
66         then
67                 if ! git commit --no-verify -C "$cmt"
68                 then
69                         echo "Commit failed, please do not call \"git commit\""
70                         echo "directly, but instead do one of the following: "
71                         die "$RESOLVEMSG"
72                 fi
73                 printf "Committed: %0${prec}d " $msgnum
74         else
75                 printf "Already applied: %0${prec}d " $msgnum
76         fi
77         git rev-list --pretty=oneline -1 "$cmt" | sed -e 's/^[^ ]* //'
78
79         prev_head=`git rev-parse HEAD^0`
80         # save the resulting commit so we can read-tree on it later
81         echo "$prev_head" > "$dotest/prev_head"
82
83         # onto the next patch:
84         msgnum=$(($msgnum + 1))
85         echo "$msgnum" >"$dotest/msgnum"
86 }
87
88 call_merge () {
89         cmt="$(cat "$dotest/cmt.$1")"
90         echo "$cmt" > "$dotest/current"
91         hd=$(git rev-parse --verify HEAD)
92         cmt_name=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
93         msgnum=$(cat "$dotest/msgnum")
94         end=$(cat "$dotest/end")
95         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
96         eval GITHEAD_$hd='$(cat "$dotest/onto_name")'
97         export GITHEAD_$cmt GITHEAD_$hd
98         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
99         rv=$?
100         case "$rv" in
101         0)
102                 unset GITHEAD_$cmt GITHEAD_$hd
103                 return
104                 ;;
105         1)
106                 git rerere
107                 die "$RESOLVEMSG"
108                 ;;
109         2)
110                 echo "Strategy: $rv $strategy failed, try another" 1>&2
111                 die "$RESOLVEMSG"
112                 ;;
113         *)
114                 die "Unknown exit code ($rv) from command:" \
115                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
116                 ;;
117         esac
118 }
119
120 move_to_original_branch () {
121         test -z "$head_name" &&
122                 head_name="$(cat "$dotest"/head-name)" &&
123                 onto="$(cat "$dotest"/onto)" &&
124                 orig_head="$(cat "$dotest"/orig-head)"
125         case "$head_name" in
126         refs/*)
127                 message="rebase finished: $head_name onto $onto"
128                 git update-ref -m "$message" \
129                         $head_name $(git rev-parse HEAD) $orig_head &&
130                 git symbolic-ref HEAD $head_name ||
131                 die "Could not move back to $head_name"
132                 ;;
133         esac
134 }
135
136 finish_rb_merge () {
137         move_to_original_branch
138         rm -r "$dotest"
139         echo "All done."
140 }
141
142 is_interactive () {
143         while test $# != 0
144         do
145                 case "$1" in
146                         -i|--interactive)
147                                 interactive_rebase=explicit
148                                 break
149                         ;;
150                         -p|--preserve-merges)
151                                 interactive_rebase=implied
152                         ;;
153                 esac
154                 shift
155         done
156
157         if [ "$interactive_rebase" = implied ]; then
158                 GIT_EDITOR=:
159                 export GIT_EDITOR
160         fi
161
162         test -n "$interactive_rebase" || test -f "$dotest"/interactive
163 }
164
165 run_pre_rebase_hook () {
166         if test -z "$OK_TO_SKIP_PRE_REBASE" &&
167            test -x "$GIT_DIR/hooks/pre-rebase"
168         then
169                 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
170                         echo >&2 "The pre-rebase hook refused to rebase."
171                         exit 1
172                 }
173         fi
174 }
175
176 test -f "$GIT_DIR"/rebase-apply/applying &&
177         die 'It looks like git-am is in progress. Cannot rebase.'
178
179 is_interactive "$@" && exec git-rebase--interactive "$@"
180
181 if test $# -eq 0
182 then
183         test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply || usage
184         test -d "$dotest" -o -f "$GIT_DIR"/rebase-apply/rebasing &&
185                 die 'A rebase is in progress, try --continue, --skip or --abort.'
186         die "No arguments given and $GIT_DIR/rebase-apply already exists."
187 fi
188
189 while test $# != 0
190 do
191         case "$1" in
192         --no-verify)
193                 OK_TO_SKIP_PRE_REBASE=yes
194                 ;;
195         --continue)
196                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
197                         die "No rebase in progress?"
198
199                 git diff-files --quiet --ignore-submodules || {
200                         echo "You must edit all merge conflicts and then"
201                         echo "mark them as resolved using git add"
202                         exit 1
203                 }
204                 if test -d "$dotest"
205                 then
206                         prev_head=$(cat "$dotest/prev_head")
207                         end=$(cat "$dotest/end")
208                         msgnum=$(cat "$dotest/msgnum")
209                         onto=$(cat "$dotest/onto")
210                         continue_merge
211                         while test "$msgnum" -le "$end"
212                         do
213                                 call_merge "$msgnum"
214                                 continue_merge
215                         done
216                         finish_rb_merge
217                         exit
218                 fi
219                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
220                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
221                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
222                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
223                 move_to_original_branch
224                 exit
225                 ;;
226         --skip)
227                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
228                         die "No rebase in progress?"
229
230                 git reset --hard HEAD || exit $?
231                 if test -d "$dotest"
232                 then
233                         git rerere clear
234                         prev_head=$(cat "$dotest/prev_head")
235                         end=$(cat "$dotest/end")
236                         msgnum=$(cat "$dotest/msgnum")
237                         msgnum=$(($msgnum + 1))
238                         onto=$(cat "$dotest/onto")
239                         while test "$msgnum" -le "$end"
240                         do
241                                 call_merge "$msgnum"
242                                 continue_merge
243                         done
244                         finish_rb_merge
245                         exit
246                 fi
247                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
248                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
249                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
250                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
251                 move_to_original_branch
252                 exit
253                 ;;
254         --abort)
255                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
256                         die "No rebase in progress?"
257
258                 git rerere clear
259                 if test -d "$dotest"
260                 then
261                         move_to_original_branch
262                 else
263                         dotest="$GIT_DIR"/rebase-apply
264                         move_to_original_branch
265                 fi
266                 git reset --hard $(cat "$dotest/orig-head")
267                 rm -r "$dotest"
268                 exit
269                 ;;
270         --onto)
271                 test 2 -le "$#" || usage
272                 newbase="$2"
273                 shift
274                 ;;
275         -M|-m|--m|--me|--mer|--merg|--merge)
276                 do_merge=t
277                 ;;
278         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
279                 --strateg=*|--strategy=*|\
280         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
281                 case "$#,$1" in
282                 *,*=*)
283                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
284                 1,*)
285                         usage ;;
286                 *)
287                         strategy="$2"
288                         shift ;;
289                 esac
290                 do_merge=t
291                 ;;
292         -v|--verbose)
293                 verbose=t
294                 ;;
295         --whitespace=*)
296                 git_am_opt="$git_am_opt $1"
297                 ;;
298         -C*)
299                 git_am_opt="$git_am_opt $1"
300                 ;;
301         --root)
302                 rebase_root=t
303                 ;;
304         -*)
305                 usage
306                 ;;
307         *)
308                 break
309                 ;;
310         esac
311         shift
312 done
313
314 # Make sure we do not have $GIT_DIR/rebase-apply
315 if test -z "$do_merge"
316 then
317         if mkdir "$GIT_DIR"/rebase-apply 2>/dev/null
318         then
319                 rmdir "$GIT_DIR"/rebase-apply
320         else
321                 echo >&2 '
322 It seems that I cannot create a rebase-apply directory, and
323 I wonder if you are in the middle of patch application or another
324 rebase.  If that is not the case, please
325         rm -fr '"$GIT_DIR"'/rebase-apply
326 and run me again.  I am stopping in case you still have something
327 valuable there.'
328                 exit 1
329         fi
330 else
331         if test -d "$dotest"
332         then
333                 die "previous rebase directory $dotest still exists." \
334                         'Try git rebase (--continue | --abort | --skip)'
335         fi
336 fi
337
338 # The tree must be really really clean.
339 if ! git update-index --ignore-submodules --refresh; then
340         echo >&2 "cannot rebase: you have unstaged changes"
341         exit 1
342 fi
343 diff=$(git diff-index --cached --name-status -r --ignore-submodules HEAD --)
344 case "$diff" in
345 ?*)     echo >&2 "cannot rebase: your index contains uncommitted changes"
346         echo >&2 "$diff"
347         exit 1
348         ;;
349 esac
350
351 if test -z "$rebase_root"
352 then
353         # The upstream head must be given.  Make sure it is valid.
354         upstream_name="$1"
355         shift
356         upstream=`git rev-parse --verify "${upstream_name}^0"` ||
357         die "invalid upstream $upstream_name"
358         unset root_flag
359         upstream_arg="$upstream_name"
360 else
361         test -z "$newbase" && die "--root must be used with --onto"
362         unset upstream_name
363         unset upstream
364         root_flag="--root"
365         upstream_arg="$root_flag"
366 fi
367
368 # Make sure the branch to rebase onto is valid.
369 onto_name=${newbase-"$upstream_name"}
370 onto=$(git rev-parse --verify "${onto_name}^0") || exit
371
372 # If a hook exists, give it a chance to interrupt
373 run_pre_rebase_hook "$upstream_arg" "$@"
374
375 # If the branch to rebase is given, that is the branch we will rebase
376 # $branch_name -- branch being rebased, or HEAD (already detached)
377 # $orig_head -- commit object name of tip of the branch before rebasing
378 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
379 switch_to=
380 case "$#" in
381 1)
382         # Is it "rebase other $branchname" or "rebase other $commit"?
383         branch_name="$1"
384         switch_to="$1"
385
386         if git show-ref --verify --quiet -- "refs/heads/$1" &&
387            branch=$(git rev-parse -q --verify "refs/heads/$1")
388         then
389                 head_name="refs/heads/$1"
390         elif branch=$(git rev-parse -q --verify "$1")
391         then
392                 head_name="detached HEAD"
393         else
394                 usage
395         fi
396         ;;
397 *)
398         # Do not need to switch branches, we are already on it.
399         if branch_name=`git symbolic-ref -q HEAD`
400         then
401                 head_name=$branch_name
402                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
403         else
404                 head_name="detached HEAD"
405                 branch_name=HEAD ;# detached
406         fi
407         branch=$(git rev-parse --verify "${branch_name}^0") || exit
408         ;;
409 esac
410 orig_head=$branch
411
412 # Now we are rebasing commits $upstream..$branch (or with --root,
413 # everything leading up to $branch) on top of $onto
414
415 # Check if we are already based on $onto with linear history,
416 # but this should be done only when upstream and onto are the same.
417 mb=$(git merge-base "$onto" "$branch")
418 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
419         # linear history?
420         ! (git rev-list --parents "$onto".."$branch" | grep " .* ") > /dev/null
421 then
422         # Lazily switch to the target branch if needed...
423         test -z "$switch_to" || git checkout "$switch_to"
424         echo >&2 "Current branch $branch_name is up to date."
425         exit 0
426 fi
427
428 if test -n "$verbose"
429 then
430         echo "Changes from $mb to $onto:"
431         # We want color (if set), but no pager
432         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
433 fi
434
435 # Detach HEAD and reset the tree
436 echo "First, rewinding head to replay your work on top of it..."
437 git checkout -q "$onto^0" || die "could not detach HEAD"
438 git update-ref ORIG_HEAD $branch
439
440 # If the $onto is a proper descendant of the tip of the branch, then
441 # we just fast forwarded.
442 if test "$mb" = "$branch"
443 then
444         echo >&2 "Fast-forwarded $branch_name to $onto_name."
445         move_to_original_branch
446         exit 0
447 fi
448
449 if test -n "$rebase_root"
450 then
451         revisions="$onto..$orig_head"
452 else
453         revisions="$upstream..$orig_head"
454 fi
455
456 if test -z "$do_merge"
457 then
458         git format-patch -k --stdout --full-index --ignore-if-in-upstream \
459                 $root_flag "$revisions" |
460         git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
461         move_to_original_branch
462         ret=$?
463         test 0 != $ret -a -d "$GIT_DIR"/rebase-apply &&
464                 echo $head_name > "$GIT_DIR"/rebase-apply/head-name &&
465                 echo $onto > "$GIT_DIR"/rebase-apply/onto &&
466                 echo $orig_head > "$GIT_DIR"/rebase-apply/orig-head
467         exit $ret
468 fi
469
470 # start doing a rebase with git-merge
471 # this is rename-aware if the recursive (default) strategy is used
472
473 mkdir -p "$dotest"
474 echo "$onto" > "$dotest/onto"
475 echo "$onto_name" > "$dotest/onto_name"
476 prev_head=$orig_head
477 echo "$prev_head" > "$dotest/prev_head"
478 echo "$orig_head" > "$dotest/orig-head"
479 echo "$head_name" > "$dotest/head-name"
480
481 msgnum=0
482 for cmt in `git rev-list --reverse --no-merges "$revisions"`
483 do
484         msgnum=$(($msgnum + 1))
485         echo "$cmt" > "$dotest/cmt.$msgnum"
486 done
487
488 echo 1 >"$dotest/msgnum"
489 echo $msgnum >"$dotest/end"
490
491 end=$msgnum
492 msgnum=1
493
494 while test "$msgnum" -le "$end"
495 do
496         call_merge "$msgnum"
497         continue_merge
498 done
499
500 finish_rb_merge