Merge branch 'maint'
[git] / git-rebase--interactive.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2006 Johannes E. Schindelin
4
5 # SHORT DESCRIPTION
6 #
7 # This script makes it easy to fix up commits in the middle of a series,
8 # and rearrange commits.
9 #
10 # The original idea comes from Eric W. Biederman, in
11 # http://article.gmane.org/gmane.comp.version-control.git/22407
12
13 USAGE='(--continue | --abort | --skip | [--preserve-merges] [--verbose]
14         [--onto <branch>] <upstream> [<branch>])'
15
16 . git-sh-setup
17 require_work_tree
18
19 DOTEST="$GIT_DIR/.dotest-merge"
20 TODO="$DOTEST"/git-rebase-todo
21 DONE="$DOTEST"/done
22 MSG="$DOTEST"/message
23 SQUASH_MSG="$DOTEST"/message-squash
24 REWRITTEN="$DOTEST"/rewritten
25 PRESERVE_MERGES=
26 STRATEGY=
27 VERBOSE=
28 test -d "$REWRITTEN" && PRESERVE_MERGES=t
29 test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
30 test -f "$DOTEST"/verbose && VERBOSE=t
31
32 warn () {
33         echo "$*" >&2
34 }
35
36 output () {
37         case "$VERBOSE" in
38         '')
39                 output=$("$@" 2>&1 )
40                 status=$?
41                 test $status != 0 && printf "%s\n" "$output"
42                 return $status
43                 ;;
44         *)
45                 "$@"
46                 ;;
47         esac
48 }
49
50 require_clean_work_tree () {
51         # test if working tree is dirty
52         git rev-parse --verify HEAD > /dev/null &&
53         git update-index --refresh &&
54         git diff-files --quiet &&
55         git diff-index --cached --quiet HEAD ||
56         die "Working tree is dirty"
57 }
58
59 ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
60
61 comment_for_reflog () {
62         case "$ORIG_REFLOG_ACTION" in
63         ''|rebase*)
64                 GIT_REFLOG_ACTION="rebase -i ($1)"
65                 export GIT_REFLOG_ACTION
66                 ;;
67         esac
68 }
69
70 mark_action_done () {
71         sed -e 1q < "$TODO" >> "$DONE"
72         sed -e 1d < "$TODO" >> "$TODO".new
73         mv -f "$TODO".new "$TODO"
74         count=$(($(grep -ve '^$' -e '^#' < "$DONE" | wc -l)))
75         total=$(($count+$(grep -ve '^$' -e '^#' < "$TODO" | wc -l)))
76         printf "Rebasing (%d/%d)\r" $count $total
77         test -z "$VERBOSE" || echo
78 }
79
80 make_patch () {
81         parent_sha1=$(git rev-parse --verify "$1"^) ||
82                 die "Cannot get patch for $1^"
83         git diff-tree -p "$parent_sha1".."$1" > "$DOTEST"/patch
84         test -f "$DOTEST"/message ||
85                 git cat-file commit "$1" | sed "1,/^$/d" > "$DOTEST"/message
86         test -f "$DOTEST"/author-script ||
87                 get_author_ident_from_commit "$1" > "$DOTEST"/author-script
88 }
89
90 die_with_patch () {
91         make_patch "$1"
92         die "$2"
93 }
94
95 die_abort () {
96         rm -rf "$DOTEST"
97         die "$1"
98 }
99
100 has_action () {
101         grep -vqe '^$' -e '^#' "$1"
102 }
103
104 pick_one () {
105         no_ff=
106         case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
107         output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
108         test -d "$REWRITTEN" &&
109                 pick_one_preserving_merges "$@" && return
110         parent_sha1=$(git rev-parse --verify $sha1^) ||
111                 die "Could not get the parent of $sha1"
112         current_sha1=$(git rev-parse --verify HEAD)
113         if test "$no_ff$current_sha1" = "$parent_sha1"; then
114                 output git reset --hard $sha1
115                 test "a$1" = a-n && output git reset --soft $current_sha1
116                 sha1=$(git rev-parse --short $sha1)
117                 output warn Fast forward to $sha1
118         else
119                 output git cherry-pick "$@"
120         fi
121 }
122
123 pick_one_preserving_merges () {
124         case "$1" in -n) sha1=$2 ;; *) sha1=$1 ;; esac
125         sha1=$(git rev-parse $sha1)
126
127         if test -f "$DOTEST"/current-commit
128         then
129                 current_commit=$(cat "$DOTEST"/current-commit) &&
130                 git rev-parse HEAD > "$REWRITTEN"/$current_commit &&
131                 rm "$DOTEST"/current-commit ||
132                 die "Cannot write current commit's replacement sha1"
133         fi
134
135         # rewrite parents; if none were rewritten, we can fast-forward.
136         fast_forward=t
137         preserve=t
138         new_parents=
139         for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -f2-)
140         do
141                 if test -f "$REWRITTEN"/$p
142                 then
143                         preserve=f
144                         new_p=$(cat "$REWRITTEN"/$p)
145                         test $p != $new_p && fast_forward=f
146                         case "$new_parents" in
147                         *$new_p*)
148                                 ;; # do nothing; that parent is already there
149                         *)
150                                 new_parents="$new_parents $new_p"
151                                 ;;
152                         esac
153                 fi
154         done
155         case $fast_forward in
156         t)
157                 output warn "Fast forward to $sha1"
158                 test $preserve = f || echo $sha1 > "$REWRITTEN"/$sha1
159                 ;;
160         f)
161                 test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
162
163                 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
164                 # detach HEAD to current parent
165                 output git checkout $first_parent 2> /dev/null ||
166                         die "Cannot move HEAD to $first_parent"
167
168                 echo $sha1 > "$DOTEST"/current-commit
169                 case "$new_parents" in
170                 ' '*' '*)
171                         # redo merge
172                         author_script=$(get_author_ident_from_commit $sha1)
173                         eval "$author_script"
174                         msg="$(git cat-file commit $sha1 | sed -e '1,/^$/d')"
175                         # No point in merging the first parent, that's HEAD
176                         new_parents=${new_parents# $first_parent}
177                         # NEEDSWORK: give rerere a chance
178                         if ! GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
179                                 GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
180                                 GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
181                                 output git merge $STRATEGY -m "$msg" \
182                                         $new_parents
183                         then
184                                 printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
185                                 die Error redoing merge $sha1
186                         fi
187                         ;;
188                 *)
189                         output git cherry-pick "$@" ||
190                                 die_with_patch $sha1 "Could not pick $sha1"
191                         ;;
192                 esac
193                 ;;
194         esac
195 }
196
197 nth_string () {
198         case "$1" in
199         *1[0-9]|*[04-9]) echo "$1"th;;
200         *1) echo "$1"st;;
201         *2) echo "$1"nd;;
202         *3) echo "$1"rd;;
203         esac
204 }
205
206 make_squash_message () {
207         if test -f "$SQUASH_MSG"; then
208                 COUNT=$(($(sed -n "s/^# This is [^0-9]*\([1-9][0-9]*\).*/\1/p" \
209                         < "$SQUASH_MSG" | tail -n 1)+1))
210                 echo "# This is a combination of $COUNT commits."
211                 sed -n "2,\$p" < "$SQUASH_MSG"
212         else
213                 COUNT=2
214                 echo "# This is a combination of two commits."
215                 echo "# The first commit's message is:"
216                 echo
217                 git cat-file commit HEAD | sed -e '1,/^$/d'
218                 echo
219         fi
220         echo "# This is the $(nth_string $COUNT) commit message:"
221         echo
222         git cat-file commit $1 | sed -e '1,/^$/d'
223 }
224
225 peek_next_command () {
226         sed -n "1s/ .*$//p" < "$TODO"
227 }
228
229 do_next () {
230         rm -f "$DOTEST"/message "$DOTEST"/author-script \
231                 "$DOTEST"/amend || exit
232         read command sha1 rest < "$TODO"
233         case "$command" in
234         '#'*|'')
235                 mark_action_done
236                 ;;
237         pick|p)
238                 comment_for_reflog pick
239
240                 mark_action_done
241                 pick_one $sha1 ||
242                         die_with_patch $sha1 "Could not apply $sha1... $rest"
243                 ;;
244         edit|e)
245                 comment_for_reflog edit
246
247                 mark_action_done
248                 pick_one $sha1 ||
249                         die_with_patch $sha1 "Could not apply $sha1... $rest"
250                 make_patch $sha1
251                 : > "$DOTEST"/amend
252                 warn
253                 warn "You can amend the commit now, with"
254                 warn
255                 warn "  git commit --amend"
256                 warn
257                 exit 0
258                 ;;
259         squash|s)
260                 comment_for_reflog squash
261
262                 has_action "$DONE" ||
263                         die "Cannot 'squash' without a previous commit"
264
265                 mark_action_done
266                 make_squash_message $sha1 > "$MSG"
267                 case "$(peek_next_command)" in
268                 squash|s)
269                         EDIT_COMMIT=
270                         USE_OUTPUT=output
271                         cp "$MSG" "$SQUASH_MSG"
272                         ;;
273                 *)
274                         EDIT_COMMIT=-e
275                         USE_OUTPUT=
276                         rm -f "$SQUASH_MSG" || exit
277                         ;;
278                 esac
279
280                 failed=f
281                 author_script=$(get_author_ident_from_commit HEAD)
282                 output git reset --soft HEAD^
283                 pick_one -n $sha1 || failed=t
284                 echo "$author_script" > "$DOTEST"/author-script
285                 case $failed in
286                 f)
287                         # This is like --amend, but with a different message
288                         eval "$author_script"
289                         GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
290                         GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
291                         GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
292                         $USE_OUTPUT git commit -F "$MSG" $EDIT_COMMIT
293                         ;;
294                 t)
295                         cp "$MSG" "$GIT_DIR"/MERGE_MSG
296                         warn
297                         warn "Could not apply $sha1... $rest"
298                         die_with_patch $sha1 ""
299                         ;;
300                 esac
301                 ;;
302         *)
303                 warn "Unknown command: $command $sha1 $rest"
304                 die_with_patch $sha1 "Please fix this in the file $TODO."
305                 ;;
306         esac
307         test -s "$TODO" && return
308
309         comment_for_reflog finish &&
310         HEADNAME=$(cat "$DOTEST"/head-name) &&
311         OLDHEAD=$(cat "$DOTEST"/head) &&
312         SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
313         if test -d "$REWRITTEN"
314         then
315                 test -f "$DOTEST"/current-commit &&
316                         current_commit=$(cat "$DOTEST"/current-commit) &&
317                         git rev-parse HEAD > "$REWRITTEN"/$current_commit
318                 NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
319         else
320                 NEWHEAD=$(git rev-parse HEAD)
321         fi &&
322         case $HEADNAME in
323         refs/*)
324                 message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
325                 git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
326                 git symbolic-ref HEAD $HEADNAME
327                 ;;
328         esac && {
329                 test ! -f "$DOTEST"/verbose ||
330                         git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
331         } &&
332         rm -rf "$DOTEST" &&
333         git gc --auto &&
334         warn "Successfully rebased and updated $HEADNAME."
335
336         exit
337 }
338
339 do_rest () {
340         while :
341         do
342                 do_next
343         done
344 }
345
346 while test $# != 0
347 do
348         case "$1" in
349         --continue)
350                 comment_for_reflog continue
351
352                 test -d "$DOTEST" || die "No interactive rebase running"
353
354                 # commit if necessary
355                 git rev-parse --verify HEAD > /dev/null &&
356                 git update-index --refresh &&
357                 git diff-files --quiet &&
358                 ! git diff-index --cached --quiet HEAD &&
359                 . "$DOTEST"/author-script && {
360                         test ! -f "$DOTEST"/amend || git reset --soft HEAD^
361                 } &&
362                 export GIT_AUTHOR_NAME GIT_AUTHOR_NAME GIT_AUTHOR_DATE &&
363                 git commit -F "$DOTEST"/message -e
364
365                 require_clean_work_tree
366                 do_rest
367                 ;;
368         --abort)
369                 comment_for_reflog abort
370
371                 test -d "$DOTEST" || die "No interactive rebase running"
372
373                 HEADNAME=$(cat "$DOTEST"/head-name)
374                 HEAD=$(cat "$DOTEST"/head)
375                 case $HEADNAME in
376                 refs/*)
377                         git symbolic-ref HEAD $HEADNAME
378                         ;;
379                 esac &&
380                 output git reset --hard $HEAD &&
381                 rm -rf "$DOTEST"
382                 exit
383                 ;;
384         --skip)
385                 comment_for_reflog skip
386
387                 test -d "$DOTEST" || die "No interactive rebase running"
388
389                 output git reset --hard && do_rest
390                 ;;
391         -s|--strategy)
392                 case "$#,$1" in
393                 *,*=*)
394                         STRATEGY="-s `expr "z$1" : 'z-[^=]*=\(.*\)'`" ;;
395                 1,*)
396                         usage ;;
397                 *)
398                         STRATEGY="-s $2"
399                         shift ;;
400                 esac
401                 ;;
402         --merge)
403                 # we use merge anyway
404                 ;;
405         -C*)
406                 die "Interactive rebase uses merge, so $1 does not make sense"
407                 ;;
408         -v|--verbose)
409                 VERBOSE=t
410                 ;;
411         -p|--preserve-merges)
412                 PRESERVE_MERGES=t
413                 ;;
414         -i|--interactive)
415                 # yeah, we know
416                 ;;
417         ''|-h)
418                 usage
419                 ;;
420         *)
421                 test -d "$DOTEST" &&
422                         die "Interactive rebase already started"
423
424                 git var GIT_COMMITTER_IDENT >/dev/null ||
425                         die "You need to set your committer info first"
426
427                 comment_for_reflog start
428
429                 ONTO=
430                 case "$1" in
431                 --onto)
432                         ONTO=$(git rev-parse --verify "$2") ||
433                                 die "Does not point to a valid commit: $2"
434                         shift; shift
435                         ;;
436                 esac
437
438                 require_clean_work_tree
439
440                 if test ! -z "$2"
441                 then
442                         output git show-ref --verify --quiet "refs/heads/$2" ||
443                                 die "Invalid branchname: $2"
444                         output git checkout "$2" ||
445                                 die "Could not checkout $2"
446                 fi
447
448                 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
449                 UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
450
451                 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
452
453                 test -z "$ONTO" && ONTO=$UPSTREAM
454
455                 : > "$DOTEST"/interactive || die "Could not mark as interactive"
456                 git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
457                         echo "detached HEAD" > "$DOTEST"/head-name
458
459                 echo $HEAD > "$DOTEST"/head
460                 echo $UPSTREAM > "$DOTEST"/upstream
461                 echo $ONTO > "$DOTEST"/onto
462                 test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
463                 test t = "$VERBOSE" && : > "$DOTEST"/verbose
464                 if test t = "$PRESERVE_MERGES"
465                 then
466                         # $REWRITTEN contains files for each commit that is
467                         # reachable by at least one merge base of $HEAD and
468                         # $UPSTREAM. They are not necessarily rewritten, but
469                         # their children might be.
470                         # This ensures that commits on merged, but otherwise
471                         # unrelated side branches are left alone. (Think "X"
472                         # in the man page's example.)
473                         mkdir "$REWRITTEN" &&
474                         for c in $(git merge-base --all $HEAD $UPSTREAM)
475                         do
476                                 echo $ONTO > "$REWRITTEN"/$c ||
477                                         die "Could not init rewritten commits"
478                         done
479                         MERGES_OPTION=
480                 else
481                         MERGES_OPTION=--no-merges
482                 fi
483
484                 SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
485                 SHORTHEAD=$(git rev-parse --short $HEAD)
486                 SHORTONTO=$(git rev-parse --short $ONTO)
487                 cat > "$TODO" << EOF
488 # Rebasing $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
489 #
490 # Commands:
491 #  pick = use commit
492 #  edit = use commit, but stop for amending
493 #  squash = use commit, but meld into previous commit
494 #
495 # If you remove a line here THAT COMMIT WILL BE LOST.
496 #
497 EOF
498                 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
499                         --abbrev=7 --reverse --left-right --cherry-pick \
500                         $UPSTREAM...$HEAD | \
501                         sed -n "s/^>/pick /p" >> "$TODO"
502
503                 has_action "$TODO" ||
504                         die_abort "Nothing to do"
505
506                 cp "$TODO" "$TODO".backup
507                 git_editor "$TODO" ||
508                         die "Could not execute editor"
509
510                 has_action "$TODO" ||
511                         die_abort "Nothing to do"
512
513                 output git checkout $ONTO && do_rest
514                 ;;
515         esac
516         shift
517 done