1#!/bin/sh
2#
3# Copyright (c) 2006 Johannes E. Schindelin
4# 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
12USAGE='(--continue | --abort | --skip | [--preserve-merges] [--verbose]
14 [--onto <branch>] <upstream> [<branch>])'
15OPTIONS_SPEC=
17. git-sh-setup
18require_work_tree
19DOTEST="$GIT_DIR/.dotest-merge"
21TODO="$DOTEST"/git-rebase-todo
22DONE="$DOTEST"/done
23MSG="$DOTEST"/message
24SQUASH_MSG="$DOTEST"/message-squash
25REWRITTEN="$DOTEST"/rewritten
26PRESERVE_MERGES=
27STRATEGY=
28VERBOSE=
29test -d "$REWRITTEN" && PRESERVE_MERGES=t
30test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
31test -f "$DOTEST"/verbose && VERBOSE=t
32warn () {
34 echo "$*" >&2
35}
36output () {
38 case "$VERBOSE" in
39 '')
40 output=$("$@" 2>&1 )
41 status=$?
42 test $status != 0 && printf "%s\n" "$output"
43 return $status
44 ;;
45 *)
46 "$@"
47 ;;
48 esac
49}
50require_clean_work_tree () {
52 # test if working tree is dirty
53 git rev-parse --verify HEAD > /dev/null &&
54 git update-index --refresh &&
55 git diff-files --quiet &&
56 git diff-index --cached --quiet HEAD ||
57 die "Working tree is dirty"
58}
59ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
61comment_for_reflog () {
63 case "$ORIG_REFLOG_ACTION" in
64 ''|rebase*)
65 GIT_REFLOG_ACTION="rebase -i ($1)"
66 export GIT_REFLOG_ACTION
67 ;;
68 esac
69}
70mark_action_done () {
72 sed -e 1q < "$TODO" >> "$DONE"
73 sed -e 1d < "$TODO" >> "$TODO".new
74 mv -f "$TODO".new "$TODO"
75 count=$(($(grep -ve '^$' -e '^#' < "$DONE" | wc -l)))
76 total=$(($count+$(grep -ve '^$' -e '^#' < "$TODO" | wc -l)))
77 printf "Rebasing (%d/%d)\r" $count $total
78 test -z "$VERBOSE" || echo
79}
80make_patch () {
82 parent_sha1=$(git rev-parse --verify "$1"^) ||
83 die "Cannot get patch for $1^"
84 git diff-tree -p "$parent_sha1".."$1" > "$DOTEST"/patch
85 test -f "$DOTEST"/message ||
86 git cat-file commit "$1" | sed "1,/^$/d" > "$DOTEST"/message
87 test -f "$DOTEST"/author-script ||
88 get_author_ident_from_commit "$1" > "$DOTEST"/author-script
89}
90die_with_patch () {
92 make_patch "$1"
93 die "$2"
94}
95die_abort () {
97 rm -rf "$DOTEST"
98 die "$1"
99}
100has_action () {
102 grep -vqe '^$' -e '^#' "$1"
103}
104pick_one () {
106 no_ff=
107 case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
108 output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
109 test -d "$REWRITTEN" &&
110 pick_one_preserving_merges "$@" && return
111 parent_sha1=$(git rev-parse --verify $sha1^) ||
112 die "Could not get the parent of $sha1"
113 current_sha1=$(git rev-parse --verify HEAD)
114 if test "$no_ff$current_sha1" = "$parent_sha1"; then
115 output git reset --hard $sha1
116 test "a$1" = a-n && output git reset --soft $current_sha1
117 sha1=$(git rev-parse --short $sha1)
118 output warn Fast forward to $sha1
119 else
120 output git cherry-pick "$@"
121 fi
122}
123pick_one_preserving_merges () {
125 case "$1" in -n) sha1=$2 ;; *) sha1=$1 ;; esac
126 sha1=$(git rev-parse $sha1)
127 if test -f "$DOTEST"/current-commit
129 then
130 current_commit=$(cat "$DOTEST"/current-commit) &&
131 git rev-parse HEAD > "$REWRITTEN"/$current_commit &&
132 rm "$DOTEST"/current-commit ||
133 die "Cannot write current commit's replacement sha1"
134 fi
135 # rewrite parents; if none were rewritten, we can fast-forward.
137 fast_forward=t
138 preserve=t
139 new_parents=
140 for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -f2-)
141 do
142 if test -f "$REWRITTEN"/$p
143 then
144 preserve=f
145 new_p=$(cat "$REWRITTEN"/$p)
146 test $p != $new_p && fast_forward=f
147 case "$new_parents" in
148 *$new_p*)
149 ;; # do nothing; that parent is already there
150 *)
151 new_parents="$new_parents $new_p"
152 ;;
153 esac
154 fi
155 done
156 case $fast_forward in
157 t)
158 output warn "Fast forward to $sha1"
159 test $preserve = f || echo $sha1 > "$REWRITTEN"/$sha1
160 ;;
161 f)
162 test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
163 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
165 # detach HEAD to current parent
166 output git checkout $first_parent 2> /dev/null ||
167 die "Cannot move HEAD to $first_parent"
168 echo $sha1 > "$DOTEST"/current-commit
170 case "$new_parents" in
171 ' '*' '*)
172 # redo merge
173 author_script=$(get_author_ident_from_commit $sha1)
174 eval "$author_script"
175 msg="$(git cat-file commit $sha1 | sed -e '1,/^$/d')"
176 # No point in merging the first parent, that's HEAD
177 new_parents=${new_parents# $first_parent}
178 # NEEDSWORK: give rerere a chance
179 if ! GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
180 GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
181 GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
182 output git merge $STRATEGY -m "$msg" \
183 $new_parents
184 then
185 printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
186 die Error redoing merge $sha1
187 fi
188 ;;
189 *)
190 output git cherry-pick "$@" ||
191 die_with_patch $sha1 "Could not pick $sha1"
192 ;;
193 esac
194 ;;
195 esac
196}
197nth_string () {
199 case "$1" in
200 *1[0-9]|*[04-9]) echo "$1"th;;
201 *1) echo "$1"st;;
202 *2) echo "$1"nd;;
203 *3) echo "$1"rd;;
204 esac
205}
206make_squash_message () {
208 if test -f "$SQUASH_MSG"; then
209 COUNT=$(($(sed -n "s/^# This is [^0-9]*\([1-9][0-9]*\).*/\1/p" \
210 < "$SQUASH_MSG" | tail -n 1)+1))
211 echo "# This is a combination of $COUNT commits."
212 sed -n "2,\$p" < "$SQUASH_MSG"
213 else
214 COUNT=2
215 echo "# This is a combination of two commits."
216 echo "# The first commit's message is:"
217 echo
218 git cat-file commit HEAD | sed -e '1,/^$/d'
219 echo
220 fi
221 echo "# This is the $(nth_string $COUNT) commit message:"
222 echo
223 git cat-file commit $1 | sed -e '1,/^$/d'
224}
225peek_next_command () {
227 sed -n "1s/ .*$//p" < "$TODO"
228}
229do_next () {
231 rm -f "$DOTEST"/message "$DOTEST"/author-script \
232 "$DOTEST"/amend || exit
233 read command sha1 rest < "$TODO"
234 case "$command" in
235 '#'*|'')
236 mark_action_done
237 ;;
238 pick|p)
239 comment_for_reflog pick
240 mark_action_done
242 pick_one $sha1 ||
243 die_with_patch $sha1 "Could not apply $sha1... $rest"
244 ;;
245 edit|e)
246 comment_for_reflog edit
247 mark_action_done
249 pick_one $sha1 ||
250 die_with_patch $sha1 "Could not apply $sha1... $rest"
251 make_patch $sha1
252 : > "$DOTEST"/amend
253 warn
254 warn "You can amend the commit now, with"
255 warn
256 warn " git commit --amend"
257 warn
258 exit 0
259 ;;
260 squash|s)
261 comment_for_reflog squash
262 has_action "$DONE" ||
264 die "Cannot 'squash' without a previous commit"
265 mark_action_done
267 make_squash_message $sha1 > "$MSG"
268 case "$(peek_next_command)" in
269 squash|s)
270 EDIT_COMMIT=
271 USE_OUTPUT=output
272 cp "$MSG" "$SQUASH_MSG"
273 ;;
274 *)
275 EDIT_COMMIT=-e
276 USE_OUTPUT=
277 rm -f "$SQUASH_MSG" || exit
278 ;;
279 esac
280 failed=f
282 author_script=$(get_author_ident_from_commit HEAD)
283 output git reset --soft HEAD^
284 pick_one -n $sha1 || failed=t
285 echo "$author_script" > "$DOTEST"/author-script
286 case $failed in
287 f)
288 # This is like --amend, but with a different message
289 eval "$author_script"
290 GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
291 GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
292 GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
293 $USE_OUTPUT git commit -F "$MSG" $EDIT_COMMIT
294 ;;
295 t)
296 cp "$MSG" "$GIT_DIR"/MERGE_MSG
297 warn
298 warn "Could not apply $sha1... $rest"
299 die_with_patch $sha1 ""
300 ;;
301 esac
302 ;;
303 *)
304 warn "Unknown command: $command $sha1 $rest"
305 die_with_patch $sha1 "Please fix this in the file $TODO."
306 ;;
307 esac
308 test -s "$TODO" && return
309 comment_for_reflog finish &&
311 HEADNAME=$(cat "$DOTEST"/head-name) &&
312 OLDHEAD=$(cat "$DOTEST"/head) &&
313 SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
314 if test -d "$REWRITTEN"
315 then
316 test -f "$DOTEST"/current-commit &&
317 current_commit=$(cat "$DOTEST"/current-commit) &&
318 git rev-parse HEAD > "$REWRITTEN"/$current_commit
319 NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
320 else
321 NEWHEAD=$(git rev-parse HEAD)
322 fi &&
323 case $HEADNAME in
324 refs/*)
325 message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
326 git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
327 git symbolic-ref HEAD $HEADNAME
328 ;;
329 esac && {
330 test ! -f "$DOTEST"/verbose ||
331 git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
332 } &&
333 rm -rf "$DOTEST" &&
334 git gc --auto &&
335 warn "Successfully rebased and updated $HEADNAME."
336 exit
338}
339do_rest () {
341 while :
342 do
343 do_next
344 done
345}
346while test $# != 0
348do
349 case "$1" in
350 --continue)
351 comment_for_reflog continue
352 test -d "$DOTEST" || die "No interactive rebase running"
354 # commit if necessary
356 git rev-parse --verify HEAD > /dev/null &&
357 git update-index --refresh &&
358 git diff-files --quiet &&
359 ! git diff-index --cached --quiet HEAD &&
360 . "$DOTEST"/author-script && {
361 test ! -f "$DOTEST"/amend || git reset --soft HEAD^
362 } &&
363 export GIT_AUTHOR_NAME GIT_AUTHOR_NAME GIT_AUTHOR_DATE &&
364 git commit -F "$DOTEST"/message -e
365 require_clean_work_tree
367 do_rest
368 ;;
369 --abort)
370 comment_for_reflog abort
371 test -d "$DOTEST" || die "No interactive rebase running"
373 HEADNAME=$(cat "$DOTEST"/head-name)
375 HEAD=$(cat "$DOTEST"/head)
376 case $HEADNAME in
377 refs/*)
378 git symbolic-ref HEAD $HEADNAME
379 ;;
380 esac &&
381 output git reset --hard $HEAD &&
382 rm -rf "$DOTEST"
383 exit
384 ;;
385 --skip)
386 comment_for_reflog skip
387 test -d "$DOTEST" || die "No interactive rebase running"
389 output git reset --hard && do_rest
391 ;;
392 -s|--strategy)
393 case "$#,$1" in
394 *,*=*)
395 STRATEGY="-s "$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
396 1,*)
397 usage ;;
398 *)
399 STRATEGY="-s $2"
400 shift ;;
401 esac
402 ;;
403 --merge)
404 # we use merge anyway
405 ;;
406 -C*)
407 die "Interactive rebase uses merge, so $1 does not make sense"
408 ;;
409 -v|--verbose)
410 VERBOSE=t
411 ;;
412 -p|--preserve-merges)
413 PRESERVE_MERGES=t
414 ;;
415 -i|--interactive)
416 # yeah, we know
417 ;;
418 ''|-h)
419 usage
420 ;;
421 *)
422 test -d "$DOTEST" &&
423 die "Interactive rebase already started"
424 git var GIT_COMMITTER_IDENT >/dev/null ||
426 die "You need to set your committer info first"
427 comment_for_reflog start
429 ONTO=
431 case "$1" in
432 --onto)
433 ONTO=$(git rev-parse --verify "$2") ||
434 die "Does not point to a valid commit: $2"
435 shift; shift
436 ;;
437 esac
438 require_clean_work_tree
440 if test ! -z "$2"
442 then
443 output git show-ref --verify --quiet "refs/heads/$2" ||
444 die "Invalid branchname: $2"
445 output git checkout "$2" ||
446 die "Could not checkout $2"
447 fi
448 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
450 UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
451 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
453 test -z "$ONTO" && ONTO=$UPSTREAM
455 : > "$DOTEST"/interactive || die "Could not mark as interactive"
457 git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
458 echo "detached HEAD" > "$DOTEST"/head-name
459 echo $HEAD > "$DOTEST"/head
461 echo $UPSTREAM > "$DOTEST"/upstream
462 echo $ONTO > "$DOTEST"/onto
463 test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
464 test t = "$VERBOSE" && : > "$DOTEST"/verbose
465 if test t = "$PRESERVE_MERGES"
466 then
467 # $REWRITTEN contains files for each commit that is
468 # reachable by at least one merge base of $HEAD and
469 # $UPSTREAM. They are not necessarily rewritten, but
470 # their children might be.
471 # This ensures that commits on merged, but otherwise
472 # unrelated side branches are left alone. (Think "X"
473 # in the man page's example.)
474 mkdir "$REWRITTEN" &&
475 for c in $(git merge-base --all $HEAD $UPSTREAM)
476 do
477 echo $ONTO > "$REWRITTEN"/$c ||
478 die "Could not init rewritten commits"
479 done
480 MERGES_OPTION=
481 else
482 MERGES_OPTION=--no-merges
483 fi
484 SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
486 SHORTHEAD=$(git rev-parse --short $HEAD)
487 SHORTONTO=$(git rev-parse --short $ONTO)
488 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
489 --abbrev=7 --reverse --left-right --cherry-pick \
490 $UPSTREAM...$HEAD | \
491 sed -n "s/^>/pick /p" > "$TODO"
492 cat >> "$TODO" << EOF
493# Rebase $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
495#
496# Commands:
497# pick = use commit
498# edit = use commit, but stop for amending
499# squash = use commit, but meld into previous commit
500#
501# If you remove a line here THAT COMMIT WILL BE LOST.
502# However, if you remove everything, the rebase will be aborted.
503#
504EOF
505 has_action "$TODO" ||
507 die_abort "Nothing to do"
508 cp "$TODO" "$TODO".backup
510 git_editor "$TODO" ||
511 die "Could not execute editor"
512 has_action "$TODO" ||
514 die_abort "Nothing to do"
515 output git checkout $ONTO && do_rest
517 ;;
518 esac
519 shift
520done