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