rebase: use @{upstream} if no upstream specified
[git] / git-rebase.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano.
4 #
5
6 USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--no-ff] [--onto <newbase>] [<upstream>|--root] [<branch>] [--quiet | -q]'
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 LF='
38 '
39 ok_to_skip_pre_rebase=
40 resolvemsg="
41 When you have resolved this problem run \"git rebase --continue\".
42 If you would prefer to skip this patch, instead run \"git rebase --skip\".
43 To restore the original branch and stop rebasing run \"git rebase --abort\".
44 "
45 unset onto
46 strategy=
47 strategy_opts=
48 do_merge=
49 merge_dir="$GIT_DIR"/rebase-merge
50 apply_dir="$GIT_DIR"/rebase-apply
51 verbose=
52 diffstat=
53 test "$(git config --bool rebase.stat)" = true && diffstat=t
54 git_am_opt=
55 rebase_root=
56 force_rebase=
57 allow_rerere_autoupdate=
58 # Non-empty if a rebase was in progress when 'git rebase' was invoked
59 in_progress=
60 # One of {am, merge, interactive}
61 type=
62 # One of {"$GIT_DIR"/rebase-apply, "$GIT_DIR"/rebase-merge}
63 state_dir=
64 # One of {'', continue, skip, abort}, as parsed from command line
65 action=
66 preserve_merges=
67 autosquash=
68 test "$(git config --bool rebase.autosquash)" = "true" && autosquash=t
69
70 read_basic_state () {
71         head_name=$(cat "$state_dir"/head-name) &&
72         onto=$(cat "$state_dir"/onto) &&
73         # We always write to orig-head, but interactive rebase used to write to
74         # head. Fall back to reading from head to cover for the case that the
75         # user upgraded git with an ongoing interactive rebase.
76         if test -f "$state_dir"/orig-head
77         then
78                 orig_head=$(cat "$state_dir"/orig-head)
79         else
80                 orig_head=$(cat "$state_dir"/head)
81         fi &&
82         GIT_QUIET=$(cat "$state_dir"/quiet) &&
83         test -f "$state_dir"/verbose && verbose=t
84         test -f "$state_dir"/strategy && strategy="$(cat "$state_dir"/strategy)"
85         test -f "$state_dir"/strategy_opts &&
86                 strategy_opts="$(cat "$state_dir"/strategy_opts)"
87         test -f "$state_dir"/allow_rerere_autoupdate &&
88                 allow_rerere_autoupdate="$(cat "$state_dir"/allow_rerere_autoupdate)"
89 }
90
91 write_basic_state () {
92         echo "$head_name" > "$state_dir"/head-name &&
93         echo "$onto" > "$state_dir"/onto &&
94         echo "$orig_head" > "$state_dir"/orig-head &&
95         echo "$GIT_QUIET" > "$state_dir"/quiet &&
96         test t = "$verbose" && : > "$state_dir"/verbose
97         test -n "$strategy" && echo "$strategy" > "$state_dir"/strategy
98         test -n "$strategy_opts" && echo "$strategy_opts" > \
99                 "$state_dir"/strategy_opts
100         test -n "$allow_rerere_autoupdate" && echo "$allow_rerere_autoupdate" > \
101                 "$state_dir"/allow_rerere_autoupdate
102 }
103
104 output () {
105         case "$verbose" in
106         '')
107                 output=$("$@" 2>&1 )
108                 status=$?
109                 test $status != 0 && printf "%s\n" "$output"
110                 return $status
111                 ;;
112         *)
113                 "$@"
114                 ;;
115         esac
116 }
117
118 move_to_original_branch () {
119         case "$head_name" in
120         refs/*)
121                 message="rebase finished: $head_name onto $onto"
122                 git update-ref -m "$message" \
123                         $head_name $(git rev-parse HEAD) $orig_head &&
124                 git symbolic-ref HEAD $head_name ||
125                 die "Could not move back to $head_name"
126                 ;;
127         esac
128 }
129
130 run_specific_rebase () {
131         if [ "$interactive_rebase" = implied ]; then
132                 GIT_EDITOR=:
133                 export GIT_EDITOR
134         fi
135         . git-rebase--$type
136 }
137
138 run_pre_rebase_hook () {
139         if test -z "$ok_to_skip_pre_rebase" &&
140            test -x "$GIT_DIR/hooks/pre-rebase"
141         then
142                 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} ||
143                 die "The pre-rebase hook refused to rebase."
144         fi
145 }
146
147 test -f "$apply_dir"/applying &&
148         die 'It looks like git-am is in progress. Cannot rebase.'
149
150 if test -d "$apply_dir"
151 then
152         type=am
153         state_dir="$apply_dir"
154 elif test -d "$merge_dir"
155 then
156         if test -f "$merge_dir"/interactive
157         then
158                 type=interactive
159                 interactive_rebase=explicit
160         else
161                 type=merge
162         fi
163         state_dir="$merge_dir"
164 fi
165 test -n "$type" && in_progress=t
166
167 total_argc=$#
168 while test $# != 0
169 do
170         case "$1" in
171         --no-verify)
172                 ok_to_skip_pre_rebase=yes
173                 ;;
174         --verify)
175                 ok_to_skip_pre_rebase=
176                 ;;
177         --continue|--skip|--abort)
178                 test $total_argc -eq 1 || usage
179                 action=${1##--}
180                 ;;
181         --onto)
182                 test 2 -le "$#" || usage
183                 onto="$2"
184                 shift
185                 ;;
186         -i|--interactive)
187                 interactive_rebase=explicit
188                 ;;
189         -p|--preserve-merges)
190                 preserve_merges=t
191                 test -z "$interactive_rebase" && interactive_rebase=implied
192                 ;;
193         --autosquash)
194                 autosquash=t
195                 ;;
196         --no-autosquash)
197                 autosquash=
198                 ;;
199         -M|-m|--m|--me|--mer|--merg|--merge)
200                 do_merge=t
201                 ;;
202         -X*|--strategy-option*)
203                 case "$#,$1" in
204                 1,-X|1,--strategy-option)
205                         usage ;;
206                 *,-X|*,--strategy-option)
207                         newopt="$2"
208                         shift ;;
209                 *,--strategy-option=*)
210                         newopt="$(expr " $1" : ' --strategy-option=\(.*\)')" ;;
211                 *,-X*)
212                         newopt="$(expr " $1" : ' -X\(.*\)')" ;;
213                 1,*)
214                         usage ;;
215                 esac
216                 strategy_opts="$strategy_opts $(git rev-parse --sq-quote "--$newopt")"
217                 do_merge=t
218                 test -z "$strategy" && strategy=recursive
219                 ;;
220         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
221                 --strateg=*|--strategy=*|\
222         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
223                 case "$#,$1" in
224                 *,*=*)
225                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
226                 1,*)
227                         usage ;;
228                 *)
229                         strategy="$2"
230                         shift ;;
231                 esac
232                 do_merge=t
233                 ;;
234         -n|--no-stat)
235                 diffstat=
236                 ;;
237         --stat)
238                 diffstat=t
239                 ;;
240         -v|--verbose)
241                 verbose=t
242                 diffstat=t
243                 GIT_QUIET=
244                 ;;
245         -q|--quiet)
246                 GIT_QUIET=t
247                 git_am_opt="$git_am_opt -q"
248                 verbose=
249                 diffstat=
250                 ;;
251         --whitespace=*)
252                 git_am_opt="$git_am_opt $1"
253                 case "$1" in
254                 --whitespace=fix|--whitespace=strip)
255                         force_rebase=t
256                         ;;
257                 esac
258                 ;;
259         --ignore-whitespace)
260                 git_am_opt="$git_am_opt $1"
261                 ;;
262         --committer-date-is-author-date|--ignore-date)
263                 git_am_opt="$git_am_opt $1"
264                 force_rebase=t
265                 ;;
266         -C*)
267                 git_am_opt="$git_am_opt $1"
268                 ;;
269         --root)
270                 rebase_root=t
271                 ;;
272         -f|--f|--fo|--for|--forc|--force|--force-r|--force-re|--force-reb|--force-reba|--force-rebas|--force-rebase|--no-ff)
273                 force_rebase=t
274                 ;;
275         --rerere-autoupdate|--no-rerere-autoupdate)
276                 allow_rerere_autoupdate="$1"
277                 ;;
278         -*)
279                 usage
280                 ;;
281         *)
282                 break
283                 ;;
284         esac
285         shift
286 done
287 test $# -gt 2 && usage
288
289 if test -n "$action"
290 then
291         test -z "$in_progress" && die "No rebase in progress?"
292         # Only interactive rebase uses detailed reflog messages
293         if test "$type" = interactive && test "$GIT_REFLOG_ACTION" = rebase
294         then
295                 GIT_REFLOG_ACTION="rebase -i ($action)"
296                 export GIT_REFLOG_ACTION
297         fi
298 fi
299
300 case "$action" in
301 continue)
302         # Sanity check
303         git rev-parse --verify HEAD >/dev/null ||
304                 die "Cannot read HEAD"
305         git update-index --ignore-submodules --refresh &&
306         git diff-files --quiet --ignore-submodules || {
307                 echo "You must edit all merge conflicts and then"
308                 echo "mark them as resolved using git add"
309                 exit 1
310         }
311         read_basic_state
312         run_specific_rebase
313         ;;
314 skip)
315         output git reset --hard HEAD || exit $?
316         read_basic_state
317         run_specific_rebase
318         ;;
319 abort)
320         git rerere clear
321         read_basic_state
322         case "$head_name" in
323         refs/*)
324                 git symbolic-ref HEAD $head_name ||
325                 die "Could not move back to $head_name"
326                 ;;
327         esac
328         output git reset --hard $orig_head
329         rm -r "$state_dir"
330         exit
331         ;;
332 esac
333
334 # Make sure no rebase is in progress
335 if test -n "$in_progress"
336 then
337         die '
338 It seems that there is already a '"${state_dir##*/}"' directory, and
339 I wonder if you are in the middle of another rebase.  If that is the
340 case, please try
341         git rebase (--continue | --abort | --skip)
342 If that is not the case, please
343         rm -fr '"$state_dir"'
344 and run me again.  I am stopping in case you still have something
345 valuable there.'
346 fi
347
348 if test -n "$interactive_rebase"
349 then
350         type=interactive
351         state_dir="$merge_dir"
352 elif test -n "$do_merge"
353 then
354         type=merge
355         state_dir="$merge_dir"
356 else
357         type=am
358         state_dir="$apply_dir"
359 fi
360
361 if test -z "$rebase_root"
362 then
363         case "$#" in
364         0)
365                 if ! upstream_name=$(git rev-parse --symbolic-full-name \
366                         --verify -q @{upstream} 2>/dev/null)
367                 then
368                         . git-parse-remote
369                         error_on_missing_default_upstream "rebase" "rebase" \
370                                 "against" "git rebase <upstream branch>"
371                 fi
372                 ;;
373         *)      upstream_name="$1"
374                 shift
375                 ;;
376         esac
377         upstream=`git rev-parse --verify "${upstream_name}^0"` ||
378         die "invalid upstream $upstream_name"
379         upstream_arg="$upstream_name"
380 else
381         test -z "$onto" && die "You must specify --onto when using --root"
382         unset upstream_name
383         unset upstream
384         upstream_arg=--root
385 fi
386
387 # Make sure the branch to rebase onto is valid.
388 onto_name=${onto-"$upstream_name"}
389 case "$onto_name" in
390 *...*)
391         if      left=${onto_name%...*} right=${onto_name#*...} &&
392                 onto=$(git merge-base --all ${left:-HEAD} ${right:-HEAD})
393         then
394                 case "$onto" in
395                 ?*"$LF"?*)
396                         die "$onto_name: there are more than one merge bases"
397                         ;;
398                 '')
399                         die "$onto_name: there is no merge base"
400                         ;;
401                 esac
402         else
403                 die "$onto_name: there is no merge base"
404         fi
405         ;;
406 *)
407         onto=$(git rev-parse --verify "${onto_name}^0") ||
408         die "Does not point to a valid commit: $1"
409         ;;
410 esac
411
412 # If the branch to rebase is given, that is the branch we will rebase
413 # $branch_name -- branch being rebased, or HEAD (already detached)
414 # $orig_head -- commit object name of tip of the branch before rebasing
415 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
416 switch_to=
417 case "$#" in
418 1)
419         # Is it "rebase other $branchname" or "rebase other $commit"?
420         branch_name="$1"
421         switch_to="$1"
422
423         if git show-ref --verify --quiet -- "refs/heads/$1" &&
424            orig_head=$(git rev-parse -q --verify "refs/heads/$1")
425         then
426                 head_name="refs/heads/$1"
427         elif orig_head=$(git rev-parse -q --verify "$1")
428         then
429                 head_name="detached HEAD"
430         else
431                 echo >&2 "fatal: no such branch: $1"
432                 usage
433         fi
434         ;;
435 *)
436         # Do not need to switch branches, we are already on it.
437         if branch_name=`git symbolic-ref -q HEAD`
438         then
439                 head_name=$branch_name
440                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
441         else
442                 head_name="detached HEAD"
443                 branch_name=HEAD ;# detached
444         fi
445         orig_head=$(git rev-parse --verify "${branch_name}^0") || exit
446         ;;
447 esac
448
449 require_clean_work_tree "rebase" "Please commit or stash them."
450
451 # Now we are rebasing commits $upstream..$orig_head (or with --root,
452 # everything leading up to $orig_head) on top of $onto
453
454 # Check if we are already based on $onto with linear history,
455 # but this should be done only when upstream and onto are the same
456 # and if this is not an interactive rebase.
457 mb=$(git merge-base "$onto" "$orig_head")
458 if test "$type" != interactive && test "$upstream" = "$onto" &&
459         test "$mb" = "$onto" &&
460         # linear history?
461         ! (git rev-list --parents "$onto".."$orig_head" | sane_grep " .* ") > /dev/null
462 then
463         if test -z "$force_rebase"
464         then
465                 # Lazily switch to the target branch if needed...
466                 test -z "$switch_to" || git checkout "$switch_to" --
467                 say "Current branch $branch_name is up to date."
468                 exit 0
469         else
470                 say "Current branch $branch_name is up to date, rebase forced."
471         fi
472 fi
473
474 # If a hook exists, give it a chance to interrupt
475 run_pre_rebase_hook "$upstream_arg" "$@"
476
477 if test -n "$diffstat"
478 then
479         if test -n "$verbose"
480         then
481                 echo "Changes from $mb to $onto:"
482         fi
483         # We want color (if set), but no pager
484         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
485 fi
486
487 test "$type" = interactive && run_specific_rebase
488
489 # Detach HEAD and reset the tree
490 say "First, rewinding head to replay your work on top of it..."
491 git checkout -q "$onto^0" || die "could not detach HEAD"
492 git update-ref ORIG_HEAD $orig_head
493
494 # If the $onto is a proper descendant of the tip of the branch, then
495 # we just fast-forwarded.
496 if test "$mb" = "$orig_head"
497 then
498         say "Fast-forwarded $branch_name to $onto_name."
499         move_to_original_branch
500         exit 0
501 fi
502
503 if test -n "$rebase_root"
504 then
505         revisions="$onto..$orig_head"
506 else
507         revisions="$upstream..$orig_head"
508 fi
509
510 run_specific_rebase