git.oblomov.eu Git - git/blob - git-legacy-rebase.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano.
   4 #
   5
   6 SUBDIRECTORY_OK=Yes
   7 OPTIONS_KEEPDASHDASH=
   8 OPTIONS_STUCKLONG=t
   9 OPTIONS_SPEC="\
  10 git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] [<upstream>] [<branch>]
  11 git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] --root [<branch>]
  12 git rebase --continue | --abort | --skip | --edit-todo
  13 --
  14  Available options are
  15 v,verbose!         display a diffstat of what changed upstream
  16 q,quiet!           be quiet. implies --no-stat
  17 autostash          automatically stash/stash pop before and after
  18 fork-point         use 'merge-base --fork-point' to refine upstream
  19 onto=!             rebase onto given branch instead of upstream
  20 r,rebase-merges?   try to rebase merges instead of skipping them
  21 p,preserve-merges! try to recreate merges instead of ignoring them
  22 s,strategy=!       use the given merge strategy
  23 X,strategy-option=! pass the argument through to the merge strategy
  24 no-ff!             cherry-pick all commits, even if unchanged
  25 f,force-rebase!    cherry-pick all commits, even if unchanged
  26 m,merge!           use merging strategies to rebase
  27 i,interactive!     let the user edit the list of commits to rebase
  28 x,exec=!           add exec lines after each commit of the editable list
  29 y=!                same as --reschedule-failed-exec -x
  30 k,keep-empty       preserve empty commits during rebase
  31 allow-empty-message allow rebasing commits with empty messages
  32 stat!              display a diffstat of what changed upstream
  33 n,no-stat!         do not show diffstat of what changed upstream
  34 verify             allow pre-rebase hook to run
  35 rerere-autoupdate  allow rerere to update index with resolved conflicts
  36 root!              rebase all reachable commits up to the root(s)
  37 autosquash         move commits that begin with squash!/fixup! under -i
  38 signoff            add a Signed-off-by: line to each commit
  39 committer-date-is-author-date! passed to 'git am'
  40 ignore-date!       passed to 'git am'
  41 whitespace=!       passed to 'git apply'
  42 ignore-whitespace! passed to 'git apply'
  43 C=!                passed to 'git apply'
  44 S,gpg-sign?        GPG-sign commits
  45  Actions:
  46 continue!          continue
  47 abort!             abort and check out the original branch
  48 skip!              skip current patch and continue
  49 edit-todo!         edit the todo list during an interactive rebase
  50 quit!              abort but keep HEAD where it is
  51 show-current-patch! show the patch file being applied or merged
  52 reschedule-failed-exec automatically reschedule failed exec commands
  53 "
  54 . git-sh-setup
  55 set_reflog_action rebase
  56 require_work_tree_exists
  57 cd_to_toplevel
  58
  59 LF='
  60 '
  61 ok_to_skip_pre_rebase=
  62
  63 squash_onto=
  64 unset onto
  65 unset restrict_revision
  66 cmd=
  67 strategy=
  68 strategy_opts=
  69 do_merge=
  70 merge_dir="$GIT_DIR"/rebase-merge
  71 apply_dir="$GIT_DIR"/rebase-apply
  72 verbose=
  73 diffstat=
  74 test "$(git config --bool rebase.stat)" = true && diffstat=t
  75 autostash="$(git config --bool rebase.autostash || echo false)"
  76 fork_point=auto
  77 git_am_opt=
  78 git_format_patch_opt=
  79 rebase_root=
  80 force_rebase=
  81 allow_rerere_autoupdate=
  82 # Non-empty if a rebase was in progress when 'git rebase' was invoked
  83 in_progress=
  84 # One of {am, merge, interactive}
  85 type=
  86 # One of {"$GIT_DIR"/rebase-apply, "$GIT_DIR"/rebase-merge}
  87 state_dir=
  88 # One of {'', continue, skip, abort}, as parsed from command line
  89 action=
  90 rebase_merges=
  91 rebase_cousins=
  92 preserve_merges=
  93 autosquash=
  94 keep_empty=
  95 allow_empty_message=--allow-empty-message
  96 signoff=
  97 reschedule_failed_exec=
  98 test "$(git config --bool rebase.autosquash)" = "true" && autosquash=t
  99 case "$(git config --bool commit.gpgsign)" in
 100 true)   gpg_sign_opt=-S ;;
 101 *)      gpg_sign_opt= ;;
 102 esac
 103 test "$(git config --bool rebase.reschedulefailedexec)" = "true" &&
 104 reschedule_failed_exec=--reschedule-failed-exec
 105 . git-rebase--common
 106
 107 read_basic_state () {
 108         test -f "$state_dir/head-name" &&
 109         test -f "$state_dir/onto" &&
 110         head_name=$(cat "$state_dir"/head-name) &&
 111         onto=$(cat "$state_dir"/onto) &&
 112         # We always write to orig-head, but interactive rebase used to write to
 113         # head. Fall back to reading from head to cover for the case that the
 114         # user upgraded git with an ongoing interactive rebase.
 115         if test -f "$state_dir"/orig-head
 116         then
 117                 orig_head=$(cat "$state_dir"/orig-head)
 118         else
 119                 orig_head=$(cat "$state_dir"/head)
 120         fi &&
 121         GIT_QUIET=$(cat "$state_dir"/quiet) &&
 122         test -f "$state_dir"/verbose && verbose=t
 123         test -f "$state_dir"/strategy && strategy="$(cat "$state_dir"/strategy)"
 124         test -f "$state_dir"/strategy_opts &&
 125                 strategy_opts="$(cat "$state_dir"/strategy_opts)"
 126         test -f "$state_dir"/allow_rerere_autoupdate &&
 127                 allow_rerere_autoupdate="$(cat "$state_dir"/allow_rerere_autoupdate)"
 128         test -f "$state_dir"/gpg_sign_opt &&
 129                 gpg_sign_opt="$(cat "$state_dir"/gpg_sign_opt)"
 130         test -f "$state_dir"/signoff && {
 131                 signoff="$(cat "$state_dir"/signoff)"
 132                 force_rebase=t
 133         }
 134         test -f "$state_dir"/reschedule-failed-exec &&
 135                 reschedule_failed_exec=t
 136 }
 137
 138 finish_rebase () {
 139         rm -f "$(git rev-parse --git-path REBASE_HEAD)"
 140         apply_autostash &&
 141         { git gc --auto || true; } &&
 142         rm -rf "$state_dir"
 143 }
 144
 145 run_interactive () {
 146         GIT_CHERRY_PICK_HELP="$resolvemsg"
 147         export GIT_CHERRY_PICK_HELP
 148
 149         test -n "$keep_empty" && keep_empty="--keep-empty"
 150         test -n "$rebase_merges" && rebase_merges="--rebase-merges"
 151         test -n "$rebase_cousins" && rebase_cousins="--rebase-cousins"
 152         test -n "$autosquash" && autosquash="--autosquash"
 153         test -n "$verbose" && verbose="--verbose"
 154         test -n "$force_rebase" && force_rebase="--no-ff"
 155         test -n "$restrict_revision" && \
 156                 restrict_revision="--restrict-revision=^$restrict_revision"
 157         test -n "$upstream" && upstream="--upstream=$upstream"
 158         test -n "$onto" && onto="--onto=$onto"
 159         test -n "$squash_onto" && squash_onto="--squash-onto=$squash_onto"
 160         test -n "$onto_name" && onto_name="--onto-name=$onto_name"
 161         test -n "$head_name" && head_name="--head-name=$head_name"
 162         test -n "$strategy" && strategy="--strategy=$strategy"
 163         test -n "$strategy_opts" && strategy_opts="--strategy-opts=$strategy_opts"
 164         test -n "$switch_to" && switch_to="--switch-to=$switch_to"
 165         test -n "$cmd" && cmd="--cmd=$cmd"
 166         test -n "$action" && action="--$action"
 167
 168         exec git rebase--interactive "$action" "$keep_empty" "$rebase_merges" "$rebase_cousins" \
 169                 "$upstream" "$onto" "$squash_onto" "$restrict_revision" \
 170                 "$allow_empty_message" "$autosquash" "$verbose" \
 171                 "$force_rebase" "$onto_name" "$head_name" "$strategy" \
 172                 "$strategy_opts" "$cmd" "$switch_to" \
 173                 "$allow_rerere_autoupdate" "$gpg_sign_opt" "$signoff" \
 174                 "$reschedule_failed_exec"
 175 }
 176
 177 run_specific_rebase () {
 178         if [ "$interactive_rebase" = implied ]; then
 179                 GIT_EDITOR=:
 180                 export GIT_EDITOR
 181                 autosquash=
 182         fi
 183
 184         if test -n "$interactive_rebase" -a -z "$preserve_merges"
 185         then
 186                 run_interactive
 187         else
 188                 . git-rebase--$type
 189
 190                 if test -z "$preserve_merges"
 191                 then
 192                         git_rebase__$type
 193                 else
 194                         git_rebase__preserve_merges
 195                 fi
 196         fi
 197
 198         ret=$?
 199         if test $ret -eq 0
 200         then
 201                 finish_rebase
 202         elif test $ret -eq 2 # special exit status for rebase -p
 203         then
 204                 apply_autostash &&
 205                 rm -rf "$state_dir" &&
 206                 die "Nothing to do"
 207         fi
 208         exit $ret
 209 }
 210
 211 run_pre_rebase_hook () {
 212         if test -z "$ok_to_skip_pre_rebase" &&
 213            test -x "$(git rev-parse --git-path hooks/pre-rebase)"
 214         then
 215                 "$(git rev-parse --git-path hooks/pre-rebase)" ${1+"$@"} ||
 216                 die "$(gettext "The pre-rebase hook refused to rebase.")"
 217         fi
 218 }
 219
 220 test -f "$apply_dir"/applying &&
 221         die "$(gettext "It looks like 'git am' is in progress. Cannot rebase.")"
 222
 223 if test -d "$apply_dir"
 224 then
 225         type=am
 226         state_dir="$apply_dir"
 227 elif test -d "$merge_dir"
 228 then
 229         if test -d "$merge_dir"/rewritten
 230         then
 231                 type=preserve-merges
 232                 interactive_rebase=explicit
 233                 preserve_merges=t
 234         elif test -f "$merge_dir"/interactive
 235         then
 236                 type=interactive
 237                 interactive_rebase=explicit
 238         else
 239                 type=merge
 240         fi
 241         state_dir="$merge_dir"
 242 fi
 243 test -n "$type" && in_progress=t
 244
 245 total_argc=$#
 246 while test $# != 0
 247 do
 248         case "$1" in
 249         --no-verify)
 250                 ok_to_skip_pre_rebase=yes
 251                 ;;
 252         --verify)
 253                 ok_to_skip_pre_rebase=
 254                 ;;
 255         --continue|--skip|--abort|--quit|--edit-todo|--show-current-patch)
 256                 test $total_argc -eq 2 || usage
 257                 action=${1##--}
 258                 ;;
 259         --onto=*)
 260                 onto="${1#--onto=}"
 261                 ;;
 262         --exec=*)
 263                 cmd="${cmd}exec ${1#--exec=}${LF}"
 264                 test -z "$interactive_rebase" && interactive_rebase=implied
 265                 ;;
 266         -y*)
 267                 reschedule_failed_exec=--reschedule-failed-exec
 268                 cmd="${cmd}exec ${1#-y}${LF}"
 269                 test -z "$interactive_rebase" && interactive_rebase=implied
 270                 ;;
 271         --interactive)
 272                 interactive_rebase=explicit
 273                 ;;
 274         --keep-empty)
 275                 keep_empty=yes
 276                 ;;
 277         --allow-empty-message)
 278                 allow_empty_message=--allow-empty-message
 279                 ;;
 280         --no-keep-empty)
 281                 keep_empty=
 282                 ;;
 283         --rebase-merges)
 284                 rebase_merges=t
 285                 test -z "$interactive_rebase" && interactive_rebase=implied
 286                 ;;
 287         --rebase-merges=*)
 288                 rebase_merges=t
 289                 case "${1#*=}" in
 290                 rebase-cousins) rebase_cousins=t;;
 291                 no-rebase-cousins) rebase_cousins=;;
 292                 *) die "Unknown mode: $1";;
 293                 esac
 294                 test -z "$interactive_rebase" && interactive_rebase=implied
 295                 ;;
 296         --preserve-merges)
 297                 preserve_merges=t
 298                 test -z "$interactive_rebase" && interactive_rebase=implied
 299                 ;;
 300         --autosquash)
 301                 autosquash=t
 302                 ;;
 303         --no-autosquash)
 304                 autosquash=
 305                 ;;
 306         --fork-point)
 307                 fork_point=t
 308                 ;;
 309         --no-fork-point)
 310                 fork_point=
 311                 ;;
 312         --merge)
 313                 do_merge=t
 314                 ;;
 315         --strategy-option=*)
 316                 strategy_opts="$strategy_opts $(git rev-parse --sq-quote "--${1#--strategy-option=}" | sed -e s/^.//)"
 317                 do_merge=t
 318                 test -z "$strategy" && strategy=recursive
 319                 ;;
 320         --strategy=*)
 321                 strategy="${1#--strategy=}"
 322                 do_merge=t
 323                 ;;
 324         --no-stat)
 325                 diffstat=
 326                 ;;
 327         --stat)
 328                 diffstat=t
 329                 ;;
 330         --autostash)
 331                 autostash=true
 332                 ;;
 333         --no-autostash)
 334                 autostash=false
 335                 ;;
 336         --verbose)
 337                 verbose=t
 338                 diffstat=t
 339                 GIT_QUIET=
 340                 ;;
 341         --quiet)
 342                 GIT_QUIET=t
 343                 git_am_opt="$git_am_opt -q"
 344                 verbose=
 345                 diffstat=
 346                 ;;
 347         --whitespace=*)
 348                 git_am_opt="$git_am_opt --whitespace=${1#--whitespace=}"
 349                 case "${1#--whitespace=}" in
 350                 fix|strip)
 351                         force_rebase=t
 352                         ;;
 353                 warn|nowarn|error|error-all)
 354                         ;; # okay, known whitespace option
 355                 *)
 356                         die "fatal: Invalid whitespace option: '${1#*=}'"
 357                         ;;
 358                 esac
 359                 ;;
 360         --ignore-whitespace)
 361                 git_am_opt="$git_am_opt $1"
 362                 ;;
 363         --signoff)
 364                 signoff=--signoff
 365                 ;;
 366         --no-signoff)
 367                 signoff=
 368                 ;;
 369         --committer-date-is-author-date|--ignore-date)
 370                 git_am_opt="$git_am_opt $1"
 371                 force_rebase=t
 372                 ;;
 373         -C*[!0-9]*)
 374                 die "fatal: switch \`C' expects a numerical value"
 375                 ;;
 376         -C*)
 377                 git_am_opt="$git_am_opt $1"
 378                 ;;
 379         --root)
 380                 rebase_root=t
 381                 ;;
 382         --force-rebase|--no-ff)
 383                 force_rebase=t
 384                 ;;
 385         --rerere-autoupdate|--no-rerere-autoupdate)
 386                 allow_rerere_autoupdate="$1"
 387                 ;;
 388         --gpg-sign)
 389                 gpg_sign_opt=-S
 390                 ;;
 391         --gpg-sign=*)
 392                 gpg_sign_opt="-S${1#--gpg-sign=}"
 393                 ;;
 394         --reschedule-failed-exec)
 395                 reschedule_failed_exec=--reschedule-failed-exec
 396                 ;;
 397         --no-reschedule-failed-exec)
 398                 reschedule_failed_exec=
 399                 ;;
 400         --)
 401                 shift
 402                 break
 403                 ;;
 404         *)
 405                 usage
 406                 ;;
 407         esac
 408         shift
 409 done
 410 test $# -gt 2 && usage
 411
 412 if test -n "$action"
 413 then
 414         test -z "$in_progress" && die "$(gettext "No rebase in progress?")"
 415         # Only interactive rebase uses detailed reflog messages
 416         if test -n "$interactive_rebase" && test "$GIT_REFLOG_ACTION" = rebase
 417         then
 418                 GIT_REFLOG_ACTION="rebase -i ($action)"
 419                 export GIT_REFLOG_ACTION
 420         fi
 421 fi
 422
 423 if test "$action" = "edit-todo" && test -z "$interactive_rebase"
 424 then
 425         die "$(gettext "The --edit-todo action can only be used during interactive rebase.")"
 426 fi
 427
 428 case "$action" in
 429 continue)
 430         # Sanity check
 431         git rev-parse --verify HEAD >/dev/null ||
 432                 die "$(gettext "Cannot read HEAD")"
 433         git update-index --ignore-submodules --refresh &&
 434         git diff-files --quiet --ignore-submodules || {
 435                 echo "$(gettext "You must edit all merge conflicts and then
 436 mark them as resolved using git add")"
 437                 exit 1
 438         }
 439         read_basic_state
 440         run_specific_rebase
 441         ;;
 442 skip)
 443         output git reset --hard HEAD || exit $?
 444         read_basic_state
 445         run_specific_rebase
 446         ;;
 447 abort)
 448         git rerere clear
 449         read_basic_state
 450         case "$head_name" in
 451         refs/*)
 452                 git symbolic-ref -m "rebase: aborting" HEAD $head_name ||
 453                 die "$(eval_gettext "Could not move back to \$head_name")"
 454                 ;;
 455         esac
 456         output git reset --hard $orig_head
 457         finish_rebase
 458         exit
 459         ;;
 460 quit)
 461         exec rm -rf "$state_dir"
 462         ;;
 463 edit-todo)
 464         run_specific_rebase
 465         ;;
 466 show-current-patch)
 467         run_specific_rebase
 468         die "BUG: run_specific_rebase is not supposed to return here"
 469         ;;
 470 esac
 471
 472 # Make sure no rebase is in progress
 473 if test -n "$in_progress"
 474 then
 475         state_dir_base=${state_dir##*/}
 476         cmd_live_rebase="git rebase (--continue | --abort | --skip)"
 477         cmd_clear_stale_rebase="rm -fr \"$state_dir\""
 478         die "
 479 $(eval_gettext 'It seems that there is already a $state_dir_base directory, and
 480 I wonder if you are in the middle of another rebase.  If that is the
 481 case, please try
 482         $cmd_live_rebase
 483 If that is not the case, please
 484         $cmd_clear_stale_rebase
 485 and run me again.  I am stopping in case you still have something
 486 valuable there.')"
 487 fi
 488
 489 if test -n "$rebase_root" && test -z "$onto"
 490 then
 491         test -z "$interactive_rebase" && interactive_rebase=implied
 492 fi
 493
 494 if test -n "$keep_empty"
 495 then
 496         test -z "$interactive_rebase" && interactive_rebase=implied
 497 fi
 498
 499 if test -n "$interactive_rebase"
 500 then
 501         if test -z "$preserve_merges"
 502         then
 503                 type=interactive
 504         else
 505                 type=preserve-merges
 506         fi
 507
 508         state_dir="$merge_dir"
 509 elif test -n "$do_merge"
 510 then
 511         type=merge
 512         state_dir="$merge_dir"
 513 else
 514         type=am
 515         state_dir="$apply_dir"
 516 fi
 517
 518 if test -t 2 && test -z "$GIT_QUIET"
 519 then
 520         git_format_patch_opt="$git_format_patch_opt --progress"
 521 fi
 522
 523 if test -n "$git_am_opt"; then
 524         incompatible_opts=$(echo " $git_am_opt " | \
 525                             sed -e 's/ -q / /g' -e 's/^ \(.*\) $/\1/')
 526         if test -n "$interactive_rebase"
 527         then
 528                 if test -n "$incompatible_opts"
 529                 then
 530                         die "$(gettext "error: cannot combine interactive options (--interactive, --exec, --rebase-merges, --preserve-merges, --keep-empty, --root + --onto) with am options ($incompatible_opts)")"
 531                 fi
 532         fi
 533         if test -n "$do_merge"; then
 534                 if test -n "$incompatible_opts"
 535                 then
 536                         die "$(gettext "error: cannot combine merge options (--merge, --strategy, --strategy-option) with am options ($incompatible_opts)")"
 537                 fi
 538         fi
 539 fi
 540
 541 if test -n "$signoff"
 542 then
 543         test -n "$preserve_merges" &&
 544                 die "$(gettext "error: cannot combine '--signoff' with '--preserve-merges'")"
 545         git_am_opt="$git_am_opt $signoff"
 546         force_rebase=t
 547 fi
 548
 549 if test -n "$preserve_merges"
 550 then
 551         # Note: incompatibility with --signoff handled in signoff block above
 552         # Note: incompatibility with --interactive is just a strong warning;
 553         #       git-rebase.txt caveats with "unless you know what you are doing"
 554         test -n "$rebase_merges" &&
 555                 die "$(gettext "error: cannot combine '--preserve-merges' with '--rebase-merges'")"
 556
 557         test -n "$reschedule_failed_exec" &&
 558                 die "$(gettext "error: cannot combine '--preserve-merges' with '--reschedule-failed-exec'")"
 559 fi
 560
 561 if test -n "$rebase_merges"
 562 then
 563         test -n "$strategy_opts" &&
 564                 die "$(gettext "error: cannot combine '--rebase-merges' with '--strategy-option'")"
 565         test -n "$strategy" &&
 566                 die "$(gettext "error: cannot combine '--rebase-merges' with '--strategy'")"
 567 fi
 568
 569 if test -z "$rebase_root"
 570 then
 571         case "$#" in
 572         0)
 573                 if ! upstream_name=$(git rev-parse --symbolic-full-name \
 574                         --verify -q @{upstream} 2>/dev/null)
 575                 then
 576                         . git-parse-remote
 577                         error_on_missing_default_upstream "rebase" "rebase" \
 578                                 "against" "git rebase $(gettext '<branch>')"
 579                 fi
 580
 581                 test "$fork_point" = auto && fork_point=t
 582                 ;;
 583         *)      upstream_name="$1"
 584                 if test "$upstream_name" = "-"
 585                 then
 586                         upstream_name="@{-1}"
 587                 fi
 588                 shift
 589                 ;;
 590         esac
 591         upstream=$(peel_committish "${upstream_name}") ||
 592         die "$(eval_gettext "invalid upstream '\$upstream_name'")"
 593         upstream_arg="$upstream_name"
 594 else
 595         if test -z "$onto"
 596         then
 597                 empty_tree=$(git hash-object -t tree /dev/null)
 598                 onto=$(git commit-tree $empty_tree </dev/null)
 599                 squash_onto="$onto"
 600         fi
 601         unset upstream_name
 602         unset upstream
 603         test $# -gt 1 && usage
 604         upstream_arg=--root
 605 fi
 606
 607 # Make sure the branch to rebase onto is valid.
 608 onto_name=${onto-"$upstream_name"}
 609 case "$onto_name" in
 610 *...*)
 611         if      left=${onto_name%...*} right=${onto_name#*...} &&
 612                 onto=$(git merge-base --all ${left:-HEAD} ${right:-HEAD})
 613         then
 614                 case "$onto" in
 615                 ?*"$LF"?*)
 616                         die "$(eval_gettext "\$onto_name: there are more than one merge bases")"
 617                         ;;
 618                 '')
 619                         die "$(eval_gettext "\$onto_name: there is no merge base")"
 620                         ;;
 621                 esac
 622         else
 623                 die "$(eval_gettext "\$onto_name: there is no merge base")"
 624         fi
 625         ;;
 626 *)
 627         onto=$(peel_committish "$onto_name") ||
 628         die "$(eval_gettext "Does not point to a valid commit: \$onto_name")"
 629         ;;
 630 esac
 631
 632 # If the branch to rebase is given, that is the branch we will rebase
 633 # $branch_name -- branch/commit being rebased, or HEAD (already detached)
 634 # $orig_head -- commit object name of tip of the branch before rebasing
 635 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
 636 switch_to=
 637 case "$#" in
 638 1)
 639         # Is it "rebase other $branchname" or "rebase other $commit"?
 640         branch_name="$1"
 641         switch_to="$1"
 642
 643         # Is it a local branch?
 644         if git show-ref --verify --quiet -- "refs/heads/$branch_name" &&
 645            orig_head=$(git rev-parse -q --verify "refs/heads/$branch_name")
 646         then
 647                 head_name="refs/heads/$branch_name"
 648         # If not is it a valid ref (branch or commit)?
 649         elif orig_head=$(git rev-parse -q --verify "$branch_name")
 650         then
 651                 head_name="detached HEAD"
 652
 653         else
 654                 die "$(eval_gettext "fatal: no such branch/commit '\$branch_name'")"
 655         fi
 656         ;;
 657 0)
 658         # Do not need to switch branches, we are already on it.
 659         if branch_name=$(git symbolic-ref -q HEAD)
 660         then
 661                 head_name=$branch_name
 662                 branch_name=$(expr "z$branch_name" : 'zrefs/heads/\(.*\)')
 663         else
 664                 head_name="detached HEAD"
 665                 branch_name=HEAD
 666         fi
 667         orig_head=$(git rev-parse --verify HEAD) || exit
 668         ;;
 669 *)
 670         die "BUG: unexpected number of arguments left to parse"
 671         ;;
 672 esac
 673
 674 if test "$fork_point" = t
 675 then
 676         new_upstream=$(git merge-base --fork-point "$upstream_name" \
 677                         "${switch_to:-HEAD}")
 678         if test -n "$new_upstream"
 679         then
 680                 restrict_revision=$new_upstream
 681         fi
 682 fi
 683
 684 if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null
 685 then
 686         stash_sha1=$(git stash create "autostash") ||
 687         die "$(gettext 'Cannot autostash')"
 688
 689         mkdir -p "$state_dir" &&
 690         echo $stash_sha1 >"$state_dir/autostash" &&
 691         stash_abbrev=$(git rev-parse --short $stash_sha1) &&
 692         echo "$(eval_gettext 'Created autostash: $stash_abbrev')" &&
 693         git reset --hard
 694 fi
 695
 696 require_clean_work_tree "rebase" "$(gettext "Please commit or stash them.")"
 697
 698 # Now we are rebasing commits $upstream..$orig_head (or with --root,
 699 # everything leading up to $orig_head) on top of $onto
 700
 701 # Check if we are already based on $onto with linear history,
 702 # but this should be done only when upstream and onto are the same
 703 # and if this is not an interactive rebase.
 704 mb=$(git merge-base "$onto" "$orig_head")
 705 if test -z "$interactive_rebase" && test "$upstream" = "$onto" &&
 706         test "$mb" = "$onto" && test -z "$restrict_revision" &&
 707         # linear history?
 708         ! (git rev-list --parents "$onto".."$orig_head" | sane_grep " .* ") > /dev/null
 709 then
 710         if test -z "$force_rebase"
 711         then
 712                 # Lazily switch to the target branch if needed...
 713                 test -z "$switch_to" ||
 714                 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $switch_to" \
 715                         git checkout -q "$switch_to" --
 716                 if test "$branch_name" = "HEAD" &&
 717                          ! git symbolic-ref -q HEAD
 718                 then
 719                         say "$(eval_gettext "HEAD is up to date.")"
 720                 else
 721                         say "$(eval_gettext "Current branch \$branch_name is up to date.")"
 722                 fi
 723                 finish_rebase
 724                 exit 0
 725         else
 726                 if test "$branch_name" = "HEAD" &&
 727                          ! git symbolic-ref -q HEAD
 728                 then
 729                         say "$(eval_gettext "HEAD is up to date, rebase forced.")"
 730                 else
 731                         say "$(eval_gettext "Current branch \$branch_name is up to date, rebase forced.")"
 732                 fi
 733         fi
 734 fi
 735
 736 # If a hook exists, give it a chance to interrupt
 737 run_pre_rebase_hook "$upstream_arg" "$@"
 738
 739 if test -n "$diffstat"
 740 then
 741         if test -n "$verbose"
 742         then
 743                 if test -z "$mb"
 744                 then
 745                         echo "$(eval_gettext "Changes to \$onto:")"
 746                 else
 747                         echo "$(eval_gettext "Changes from \$mb to \$onto:")"
 748                 fi
 749         fi
 750         mb_tree="${mb:-$(git hash-object -t tree /dev/null)}"
 751         # We want color (if set), but no pager
 752         GIT_PAGER='' git diff --stat --summary "$mb_tree" "$onto"
 753 fi
 754
 755 test -n "$interactive_rebase" && run_specific_rebase
 756
 757 # Detach HEAD and reset the tree
 758 say "$(gettext "First, rewinding head to replay your work on top of it...")"
 759
 760 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name" \
 761         git checkout -q "$onto^0" || die "could not detach HEAD"
 762 git update-ref ORIG_HEAD $orig_head
 763
 764 # If the $onto is a proper descendant of the tip of the branch, then
 765 # we just fast-forwarded.
 766 if test "$mb" = "$orig_head"
 767 then
 768         say "$(eval_gettext "Fast-forwarded \$branch_name to \$onto_name.")"
 769         move_to_original_branch
 770         finish_rebase
 771         exit 0
 772 fi
 773
 774 if test -n "$rebase_root"
 775 then
 776         revisions="$onto..$orig_head"
 777 else
 778         revisions="${restrict_revision-$upstream}..$orig_head"
 779 fi
 780
 781 run_specific_rebase