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 OPTIONS_KEEPDASHDASH=
  14 OPTIONS_SPEC="\
  15 git-rebase [-i] [options] [--] <upstream> [<branch>]
  16 git-rebase [-i] (--continue | --abort | --skip)
  17 --
  18  Available options are
  19 v,verbose          display a diffstat of what changed upstream
  20 onto=              rebase onto given branch instead of upstream
  21 p,preserve-merges  try to recreate merges instead of ignoring them
  22 s,strategy=        use the given merge strategy
  23 m,merge            always used (no-op)
  24 i,interactive      always used (no-op)
  25  Actions:
  26 continue           continue rebasing process
  27 abort              abort rebasing process and restore original branch
  28 skip               skip current patch and continue rebasing process
  29 no-verify          override pre-rebase hook from stopping the operation
  30 root               rebase all reachable commmits up to the root(s)
  31 "
  32
  33 . git-sh-setup
  34 require_work_tree
  35
  36 DOTEST="$GIT_DIR/rebase-merge"
  37
  38 # The file containing rebase commands, comments, and empty lines.
  39 # This file is created by "git rebase -i" then edited by the user.  As
  40 # the lines are processed, they are removed from the front of this
  41 # file and written to the tail of $DONE.
  42 TODO="$DOTEST"/git-rebase-todo
  43
  44 # The rebase command lines that have already been processed.  A line
  45 # is moved here when it is first handled, before any associated user
  46 # actions.
  47 DONE="$DOTEST"/done
  48
  49 # The commit message that is planned to be used for any changes that
  50 # need to be committed following a user interaction.
  51 MSG="$DOTEST"/message
  52
  53 # The file into which is accumulated the suggested commit message for
  54 # squash/fixup commands.  When the first of a series of squash/fixups
  55 # is seen, the file is created and the commit message from the
  56 # previous commit and from the first squash/fixup commit are written
  57 # to it.  The commit message for each subsequent squash/fixup commit
  58 # is appended to the file as it is processed.
  59 #
  60 # The first line of the file is of the form
  61 #     # This is a combination of $COUNT commits.
  62 # where $COUNT is the number of commits whose messages have been
  63 # written to the file so far (including the initial "pick" commit).
  64 # Each time that a commit message is processed, this line is read and
  65 # updated.  It is deleted just before the combined commit is made.
  66 SQUASH_MSG="$DOTEST"/message-squash
  67
  68 # $REWRITTEN is the name of a directory containing files for each
  69 # commit that is reachable by at least one merge base of $HEAD and
  70 # $UPSTREAM. They are not necessarily rewritten, but their children
  71 # might be.  This ensures that commits on merged, but otherwise
  72 # unrelated side branches are left alone. (Think "X" in the man page's
  73 # example.)
  74 REWRITTEN="$DOTEST"/rewritten
  75
  76 DROPPED="$DOTEST"/dropped
  77
  78 # A script to set the GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
  79 # GIT_AUTHOR_DATE that will be used for the commit that is currently
  80 # being rebased.
  81 AUTHOR_SCRIPT="$DOTEST"/author-script
  82
  83 # When an "edit" rebase command is being processed, the SHA1 of the
  84 # commit to be edited is recorded in this file.  When "git rebase
  85 # --continue" is executed, if there are any staged changes then they
  86 # will be amended to the HEAD commit, but only provided the HEAD
  87 # commit is still the commit to be edited.  When any other rebase
  88 # command is processed, this file is deleted.
  89 AMEND="$DOTEST"/amend
  90
  91 PRESERVE_MERGES=
  92 STRATEGY=
  93 ONTO=
  94 VERBOSE=
  95 OK_TO_SKIP_PRE_REBASE=
  96 REBASE_ROOT=
  97
  98 GIT_CHERRY_PICK_HELP="  After resolving the conflicts,
  99 mark the corrected paths with 'git add <paths>', and
 100 run 'git rebase --continue'"
 101 export GIT_CHERRY_PICK_HELP
 102
 103 warn () {
 104         echo "$*" >&2
 105 }
 106
 107 output () {
 108         case "$VERBOSE" in
 109         '')
 110                 output=$("$@" 2>&1 )
 111                 status=$?
 112                 test $status != 0 && printf "%s\n" "$output"
 113                 return $status
 114                 ;;
 115         *)
 116                 "$@"
 117                 ;;
 118         esac
 119 }
 120
 121 # Output the commit message for the specified commit.
 122 commit_message () {
 123         git cat-file commit "$1" | sed "1,/^$/d"
 124 }
 125
 126 run_pre_rebase_hook () {
 127         if test -z "$OK_TO_SKIP_PRE_REBASE" &&
 128            test -x "$GIT_DIR/hooks/pre-rebase"
 129         then
 130                 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 131                         echo >&2 "The pre-rebase hook refused to rebase."
 132                         exit 1
 133                 }
 134         fi
 135 }
 136
 137 require_clean_work_tree () {
 138         # test if working tree is dirty
 139         git rev-parse --verify HEAD > /dev/null &&
 140         git update-index --ignore-submodules --refresh &&
 141         git diff-files --quiet --ignore-submodules &&
 142         git diff-index --cached --quiet HEAD --ignore-submodules -- ||
 143         die "Working tree is dirty"
 144 }
 145
 146 ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
 147
 148 comment_for_reflog () {
 149         case "$ORIG_REFLOG_ACTION" in
 150         ''|rebase*)
 151                 GIT_REFLOG_ACTION="rebase -i ($1)"
 152                 export GIT_REFLOG_ACTION
 153                 ;;
 154         esac
 155 }
 156
 157 last_count=
 158 mark_action_done () {
 159         sed -e 1q < "$TODO" >> "$DONE"
 160         sed -e 1d < "$TODO" >> "$TODO".new
 161         mv -f "$TODO".new "$TODO"
 162         count=$(sane_grep -c '^[^#]' < "$DONE")
 163         total=$(($count+$(sane_grep -c '^[^#]' < "$TODO")))
 164         if test "$last_count" != "$count"
 165         then
 166                 last_count=$count
 167                 printf "Rebasing (%d/%d)\r" $count $total
 168                 test -z "$VERBOSE" || echo
 169         fi
 170 }
 171
 172 make_patch () {
 173         sha1_and_parents="$(git rev-list --parents -1 "$1")"
 174         case "$sha1_and_parents" in
 175         ?*' '?*' '?*)
 176                 git diff --cc $sha1_and_parents
 177                 ;;
 178         ?*' '?*)
 179                 git diff-tree -p "$1^!"
 180                 ;;
 181         *)
 182                 echo "Root commit"
 183                 ;;
 184         esac > "$DOTEST"/patch
 185         test -f "$MSG" ||
 186                 commit_message "$1" > "$MSG"
 187         test -f "$AUTHOR_SCRIPT" ||
 188                 get_author_ident_from_commit "$1" > "$AUTHOR_SCRIPT"
 189 }
 190
 191 die_with_patch () {
 192         make_patch "$1"
 193         git rerere
 194         die "$2"
 195 }
 196
 197 die_abort () {
 198         rm -rf "$DOTEST"
 199         die "$1"
 200 }
 201
 202 has_action () {
 203         sane_grep '^[^#]' "$1" >/dev/null
 204 }
 205
 206 # Run command with GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
 207 # GIT_AUTHOR_DATE exported from the current environment.
 208 do_with_author () {
 209         GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
 210         GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
 211         GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
 212         "$@"
 213 }
 214
 215 pick_one () {
 216         no_ff=
 217         case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
 218         output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
 219         test -d "$REWRITTEN" &&
 220                 pick_one_preserving_merges "$@" && return
 221         if test -n "$REBASE_ROOT"
 222         then
 223                 output git cherry-pick "$@"
 224                 return
 225         fi
 226         parent_sha1=$(git rev-parse --verify $sha1^) ||
 227                 die "Could not get the parent of $sha1"
 228         current_sha1=$(git rev-parse --verify HEAD)
 229         if test -z "$no_ff" -a "$current_sha1" = "$parent_sha1"
 230         then
 231                 output git reset --hard $sha1
 232                 output warn Fast-forward to $(git rev-parse --short $sha1)
 233         else
 234                 output git cherry-pick "$@"
 235         fi
 236 }
 237
 238 pick_one_preserving_merges () {
 239         fast_forward=t
 240         case "$1" in
 241         -n)
 242                 fast_forward=f
 243                 sha1=$2
 244                 ;;
 245         *)
 246                 sha1=$1
 247                 ;;
 248         esac
 249         sha1=$(git rev-parse $sha1)
 250
 251         if test -f "$DOTEST"/current-commit
 252         then
 253                 if test "$fast_forward" = t
 254                 then
 255                         cat "$DOTEST"/current-commit | while read current_commit
 256                         do
 257                                 git rev-parse HEAD > "$REWRITTEN"/$current_commit
 258                         done
 259                         rm "$DOTEST"/current-commit ||
 260                         die "Cannot write current commit's replacement sha1"
 261                 fi
 262         fi
 263
 264         echo $sha1 >> "$DOTEST"/current-commit
 265
 266         # rewrite parents; if none were rewritten, we can fast-forward.
 267         new_parents=
 268         pend=" $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)"
 269         if test "$pend" = " "
 270         then
 271                 pend=" root"
 272         fi
 273         while [ "$pend" != "" ]
 274         do
 275                 p=$(expr "$pend" : ' \([^ ]*\)')
 276                 pend="${pend# $p}"
 277
 278                 if test -f "$REWRITTEN"/$p
 279                 then
 280                         new_p=$(cat "$REWRITTEN"/$p)
 281
 282                         # If the todo reordered commits, and our parent is marked for
 283                         # rewriting, but hasn't been gotten to yet, assume the user meant to
 284                         # drop it on top of the current HEAD
 285                         if test -z "$new_p"
 286                         then
 287                                 new_p=$(git rev-parse HEAD)
 288                         fi
 289
 290                         test $p != $new_p && fast_forward=f
 291                         case "$new_parents" in
 292                         *$new_p*)
 293                                 ;; # do nothing; that parent is already there
 294                         *)
 295                                 new_parents="$new_parents $new_p"
 296                                 ;;
 297                         esac
 298                 else
 299                         if test -f "$DROPPED"/$p
 300                         then
 301                                 fast_forward=f
 302                                 replacement="$(cat "$DROPPED"/$p)"
 303                                 test -z "$replacement" && replacement=root
 304                                 pend=" $replacement$pend"
 305                         else
 306                                 new_parents="$new_parents $p"
 307                         fi
 308                 fi
 309         done
 310         case $fast_forward in
 311         t)
 312                 output warn "Fast-forward to $sha1"
 313                 output git reset --hard $sha1 ||
 314                         die "Cannot fast-forward to $sha1"
 315                 ;;
 316         f)
 317                 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
 318
 319                 if [ "$1" != "-n" ]
 320                 then
 321                         # detach HEAD to current parent
 322                         output git checkout $first_parent 2> /dev/null ||
 323                                 die "Cannot move HEAD to $first_parent"
 324                 fi
 325
 326                 case "$new_parents" in
 327                 ' '*' '*)
 328                         test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
 329
 330                         # redo merge
 331                         author_script=$(get_author_ident_from_commit $sha1)
 332                         eval "$author_script"
 333                         msg="$(commit_message $sha1)"
 334                         # No point in merging the first parent, that's HEAD
 335                         new_parents=${new_parents# $first_parent}
 336                         if ! do_with_author output \
 337                                 git merge $STRATEGY -m "$msg" $new_parents
 338                         then
 339                                 printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
 340                                 die_with_patch $sha1 "Error redoing merge $sha1"
 341                         fi
 342                         ;;
 343                 *)
 344                         output git cherry-pick "$@" ||
 345                                 die_with_patch $sha1 "Could not pick $sha1"
 346                         ;;
 347                 esac
 348                 ;;
 349         esac
 350 }
 351
 352 nth_string () {
 353         case "$1" in
 354         *1[0-9]|*[04-9]) echo "$1"th;;
 355         *1) echo "$1"st;;
 356         *2) echo "$1"nd;;
 357         *3) echo "$1"rd;;
 358         esac
 359 }
 360
 361 update_squash_message () {
 362         if test -f "$SQUASH_MSG"; then
 363                 mv "$SQUASH_MSG" "$SQUASH_MSG".bak || exit
 364                 COUNT=$(($(sed -n \
 365                         -e "1s/^# This is a combination of \(.*\) commits\./\1/p" \
 366                         -e "q" < "$SQUASH_MSG".bak)+1))
 367                 {
 368                         echo "# This is a combination of $COUNT commits."
 369                         sed -e 1d -e '2,/^./{
 370                                 /^$/d
 371                         }' <"$SQUASH_MSG".bak
 372                 } >$SQUASH_MSG
 373         else
 374                 COUNT=2
 375                 {
 376                         echo "# This is a combination of 2 commits."
 377                         echo "# The first commit's message is:"
 378                         echo
 379                         commit_message HEAD
 380                 } >$SQUASH_MSG
 381         fi
 382         case $1 in
 383         squash)
 384                 echo
 385                 echo "# This is the $(nth_string $COUNT) commit message:"
 386                 echo
 387                 commit_message $2
 388                 ;;
 389         fixup)
 390                 echo
 391                 echo "# The $(nth_string $COUNT) commit message will be skipped:"
 392                 echo
 393                 commit_message $2 | sed -e 's/^/#       /'
 394                 ;;
 395         esac >>$SQUASH_MSG
 396 }
 397
 398 peek_next_command () {
 399         sed -n -e "/^#/d" -e "/^$/d" -e "s/ .*//p" -e "q" < "$TODO"
 400 }
 401
 402 do_next () {
 403         rm -f "$MSG" "$AUTHOR_SCRIPT" "$AMEND" || exit
 404         read command sha1 rest < "$TODO"
 405         case "$command" in
 406         '#'*|''|noop)
 407                 mark_action_done
 408                 ;;
 409         pick|p)
 410                 comment_for_reflog pick
 411
 412                 mark_action_done
 413                 pick_one $sha1 ||
 414                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 415                 ;;
 416         reword|r)
 417                 comment_for_reflog reword
 418
 419                 mark_action_done
 420                 pick_one $sha1 ||
 421                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 422                 git commit --amend
 423                 ;;
 424         edit|e)
 425                 comment_for_reflog edit
 426
 427                 mark_action_done
 428                 pick_one $sha1 ||
 429                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 430                 make_patch $sha1
 431                 git rev-parse --verify HEAD > "$AMEND"
 432                 warn "Stopped at $sha1... $rest"
 433                 warn "You can amend the commit now, with"
 434                 warn
 435                 warn "  git commit --amend"
 436                 warn
 437                 warn "Once you are satisfied with your changes, run"
 438                 warn
 439                 warn "  git rebase --continue"
 440                 warn
 441                 exit 0
 442                 ;;
 443         squash|s|fixup|f)
 444                 case "$command" in
 445                 squash|s)
 446                         squash_style=squash
 447                         ;;
 448                 fixup|f)
 449                         squash_style=fixup
 450                         ;;
 451                 esac
 452                 comment_for_reflog $squash_style
 453
 454                 test -f "$DONE" && has_action "$DONE" ||
 455                         die "Cannot '$squash_style' without a previous commit"
 456
 457                 mark_action_done
 458                 update_squash_message $squash_style $sha1
 459                 failed=f
 460                 author_script=$(get_author_ident_from_commit HEAD)
 461                 echo "$author_script" > "$AUTHOR_SCRIPT"
 462                 eval "$author_script"
 463                 output git reset --soft HEAD^
 464                 pick_one -n $sha1 || failed=t
 465                 case "$(peek_next_command)" in
 466                 squash|s|fixup|f)
 467                         USE_OUTPUT=output
 468                         cp "$SQUASH_MSG" "$MSG" || exit
 469                         MSG_OPT=-F
 470                         EDIT_OR_FILE="$MSG"
 471                         ;;
 472                 *)
 473                         USE_OUTPUT=
 474                         MSG_OPT=
 475                         EDIT_OR_FILE=-e
 476                         cp "$SQUASH_MSG" "$MSG" || exit
 477                         mv "$SQUASH_MSG" "$GIT_DIR"/SQUASH_MSG || exit
 478                         rm -f "$GIT_DIR"/MERGE_MSG || exit
 479                         ;;
 480                 esac
 481                 if test $failed = f
 482                 then
 483                         # This is like --amend, but with a different message
 484                         do_with_author $USE_OUTPUT git commit --no-verify \
 485                                 $MSG_OPT "$EDIT_OR_FILE" ||
 486                                 failed=t
 487                 fi
 488                 if test $failed = t
 489                 then
 490                         cp "$MSG" "$GIT_DIR"/MERGE_MSG
 491                         warn
 492                         warn "Could not apply $sha1... $rest"
 493                         die_with_patch $sha1 ""
 494                 fi
 495                 ;;
 496         *)
 497                 warn "Unknown command: $command $sha1 $rest"
 498                 if git rev-parse --verify -q "$sha1" >/dev/null
 499                 then
 500                         die_with_patch $sha1 "Please fix this in the file $TODO."
 501                 else
 502                         die "Please fix this in the file $TODO."
 503                 fi
 504                 ;;
 505         esac
 506         test -s "$TODO" && return
 507
 508         comment_for_reflog finish &&
 509         HEADNAME=$(cat "$DOTEST"/head-name) &&
 510         OLDHEAD=$(cat "$DOTEST"/head) &&
 511         SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
 512         NEWHEAD=$(git rev-parse HEAD) &&
 513         case $HEADNAME in
 514         refs/*)
 515                 message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO" &&
 516                 git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
 517                 git symbolic-ref HEAD $HEADNAME
 518                 ;;
 519         esac && {
 520                 test ! -f "$DOTEST"/verbose ||
 521                         git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
 522         } &&
 523         rm -rf "$DOTEST" &&
 524         git gc --auto &&
 525         warn "Successfully rebased and updated $HEADNAME."
 526
 527         exit
 528 }
 529
 530 do_rest () {
 531         while :
 532         do
 533                 do_next
 534         done
 535 }
 536
 537 # skip picking commits whose parents are unchanged
 538 skip_unnecessary_picks () {
 539         fd=3
 540         while read command sha1 rest
 541         do
 542                 # fd=3 means we skip the command
 543                 case "$fd,$command,$(git rev-parse --verify --quiet $sha1^)" in
 544                 3,pick,"$ONTO"*|3,p,"$ONTO"*)
 545                         # pick a commit whose parent is current $ONTO -> skip
 546                         ONTO=$sha1
 547                         ;;
 548                 3,#*|3,,*)
 549                         # copy comments
 550                         ;;
 551                 *)
 552                         fd=1
 553                         ;;
 554                 esac
 555                 echo "$command${sha1:+ }$sha1${rest:+ }$rest" >&$fd
 556         done <"$TODO" >"$TODO.new" 3>>"$DONE" &&
 557         mv -f "$TODO".new "$TODO" ||
 558         die "Could not skip unnecessary pick commands"
 559 }
 560
 561 # check if no other options are set
 562 is_standalone () {
 563         test $# -eq 2 -a "$2" = '--' &&
 564         test -z "$ONTO" &&
 565         test -z "$PRESERVE_MERGES" &&
 566         test -z "$STRATEGY" &&
 567         test -z "$VERBOSE"
 568 }
 569
 570 get_saved_options () {
 571         test -d "$REWRITTEN" && PRESERVE_MERGES=t
 572         test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
 573         test -f "$DOTEST"/verbose && VERBOSE=t
 574         test -f "$DOTEST"/rebase-root && REBASE_ROOT=t
 575 }
 576
 577 while test $# != 0
 578 do
 579         case "$1" in
 580         --no-verify)
 581                 OK_TO_SKIP_PRE_REBASE=yes
 582                 ;;
 583         --verify)
 584                 ;;
 585         --continue)
 586                 is_standalone "$@" || usage
 587                 get_saved_options
 588                 comment_for_reflog continue
 589
 590                 test -d "$DOTEST" || die "No interactive rebase running"
 591
 592                 # Sanity check
 593                 git rev-parse --verify HEAD >/dev/null ||
 594                         die "Cannot read HEAD"
 595                 git update-index --ignore-submodules --refresh &&
 596                         git diff-files --quiet --ignore-submodules ||
 597                         die "Working tree is dirty"
 598
 599                 # do we have anything to commit?
 600                 if git diff-index --cached --quiet --ignore-submodules HEAD --
 601                 then
 602                         : Nothing to commit -- skip this
 603                 else
 604                         . "$AUTHOR_SCRIPT" ||
 605                                 die "Cannot find the author identity"
 606                         amend=
 607                         if test -f "$AMEND"
 608                         then
 609                                 amend=$(git rev-parse --verify HEAD)
 610                                 test "$amend" = $(cat "$AMEND") ||
 611                                 die "\
 612 You have uncommitted changes in your working tree. Please, commit them
 613 first and then run 'git rebase --continue' again."
 614                                 git reset --soft HEAD^ ||
 615                                 die "Cannot rewind the HEAD"
 616                         fi
 617                         do_with_author git commit --no-verify -F "$MSG" -e || {
 618                                 test -n "$amend" && git reset --soft $amend
 619                                 die "Could not commit staged changes."
 620                         }
 621                 fi
 622
 623                 require_clean_work_tree
 624                 do_rest
 625                 ;;
 626         --abort)
 627                 is_standalone "$@" || usage
 628                 get_saved_options
 629                 comment_for_reflog abort
 630
 631                 git rerere clear
 632                 test -d "$DOTEST" || die "No interactive rebase running"
 633
 634                 HEADNAME=$(cat "$DOTEST"/head-name)
 635                 HEAD=$(cat "$DOTEST"/head)
 636                 case $HEADNAME in
 637                 refs/*)
 638                         git symbolic-ref HEAD $HEADNAME
 639                         ;;
 640                 esac &&
 641                 output git reset --hard $HEAD &&
 642                 rm -rf "$DOTEST"
 643                 exit
 644                 ;;
 645         --skip)
 646                 is_standalone "$@" || usage
 647                 get_saved_options
 648                 comment_for_reflog skip
 649
 650                 git rerere clear
 651                 test -d "$DOTEST" || die "No interactive rebase running"
 652
 653                 output git reset --hard && do_rest
 654                 ;;
 655         -s)
 656                 case "$#,$1" in
 657                 *,*=*)
 658                         STRATEGY="-s "$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
 659                 1,*)
 660                         usage ;;
 661                 *)
 662                         STRATEGY="-s $2"
 663                         shift ;;
 664                 esac
 665                 ;;
 666         -m)
 667                 # we use merge anyway
 668                 ;;
 669         -v)
 670                 VERBOSE=t
 671                 ;;
 672         -p)
 673                 PRESERVE_MERGES=t
 674                 ;;
 675         -i)
 676                 # yeah, we know
 677                 ;;
 678         --root)
 679                 REBASE_ROOT=t
 680                 ;;
 681         --onto)
 682                 shift
 683                 ONTO=$(git rev-parse --verify "$1") ||
 684                         die "Does not point to a valid commit: $1"
 685                 ;;
 686         --)
 687                 shift
 688                 test -z "$REBASE_ROOT" -a $# -ge 1 -a $# -le 2 ||
 689                 test ! -z "$REBASE_ROOT" -a $# -le 1 || usage
 690                 test -d "$DOTEST" &&
 691                         die "Interactive rebase already started"
 692
 693                 git var GIT_COMMITTER_IDENT >/dev/null ||
 694                         die "You need to set your committer info first"
 695
 696                 if test -z "$REBASE_ROOT"
 697                 then
 698                         UPSTREAM_ARG="$1"
 699                         UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
 700                         test -z "$ONTO" && ONTO=$UPSTREAM
 701                         shift
 702                 else
 703                         UPSTREAM=
 704                         UPSTREAM_ARG=--root
 705                         test -z "$ONTO" &&
 706                                 die "You must specify --onto when using --root"
 707                 fi
 708                 run_pre_rebase_hook "$UPSTREAM_ARG" "$@"
 709
 710                 comment_for_reflog start
 711
 712                 require_clean_work_tree
 713
 714                 if test ! -z "$1"
 715                 then
 716                         output git show-ref --verify --quiet "refs/heads/$1" ||
 717                                 die "Invalid branchname: $1"
 718                         output git checkout "$1" ||
 719                                 die "Could not checkout $1"
 720                 fi
 721
 722                 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
 723                 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
 724
 725                 : > "$DOTEST"/interactive || die "Could not mark as interactive"
 726                 git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
 727                         echo "detached HEAD" > "$DOTEST"/head-name
 728
 729                 echo $HEAD > "$DOTEST"/head
 730                 case "$REBASE_ROOT" in
 731                 '')
 732                         rm -f "$DOTEST"/rebase-root ;;
 733                 *)
 734                         : >"$DOTEST"/rebase-root ;;
 735                 esac
 736                 echo $ONTO > "$DOTEST"/onto
 737                 test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
 738                 test t = "$VERBOSE" && : > "$DOTEST"/verbose
 739                 if test t = "$PRESERVE_MERGES"
 740                 then
 741                         if test -z "$REBASE_ROOT"
 742                         then
 743                                 mkdir "$REWRITTEN" &&
 744                                 for c in $(git merge-base --all $HEAD $UPSTREAM)
 745                                 do
 746                                         echo $ONTO > "$REWRITTEN"/$c ||
 747                                                 die "Could not init rewritten commits"
 748                                 done
 749                         else
 750                                 mkdir "$REWRITTEN" &&
 751                                 echo $ONTO > "$REWRITTEN"/root ||
 752                                         die "Could not init rewritten commits"
 753                         fi
 754                         # No cherry-pick because our first pass is to determine
 755                         # parents to rewrite and skipping dropped commits would
 756                         # prematurely end our probe
 757                         MERGES_OPTION=
 758                         first_after_upstream="$(git rev-list --reverse --first-parent $UPSTREAM..$HEAD | head -n 1)"
 759                 else
 760                         MERGES_OPTION="--no-merges --cherry-pick"
 761                 fi
 762
 763                 SHORTHEAD=$(git rev-parse --short $HEAD)
 764                 SHORTONTO=$(git rev-parse --short $ONTO)
 765                 if test -z "$REBASE_ROOT"
 766                         # this is now equivalent to ! -z "$UPSTREAM"
 767                 then
 768                         SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
 769                         REVISIONS=$UPSTREAM...$HEAD
 770                         SHORTREVISIONS=$SHORTUPSTREAM..$SHORTHEAD
 771                 else
 772                         REVISIONS=$ONTO...$HEAD
 773                         SHORTREVISIONS=$SHORTHEAD
 774                 fi
 775                 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
 776                         --abbrev=7 --reverse --left-right --topo-order \
 777                         $REVISIONS | \
 778                         sed -n "s/^>//p" | while read shortsha1 rest
 779                 do
 780                         if test t != "$PRESERVE_MERGES"
 781                         then
 782                                 echo "pick $shortsha1 $rest" >> "$TODO"
 783                         else
 784                                 sha1=$(git rev-parse $shortsha1)
 785                                 if test -z "$REBASE_ROOT"
 786                                 then
 787                                         preserve=t
 788                                         for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)
 789                                         do
 790                                                 if test -f "$REWRITTEN"/$p -a \( $p != $ONTO -o $sha1 = $first_after_upstream \)
 791                                                 then
 792                                                         preserve=f
 793                                                 fi
 794                                         done
 795                                 else
 796                                         preserve=f
 797                                 fi
 798                                 if test f = "$preserve"
 799                                 then
 800                                         touch "$REWRITTEN"/$sha1
 801                                         echo "pick $shortsha1 $rest" >> "$TODO"
 802                                 fi
 803                         fi
 804                 done
 805
 806                 # Watch for commits that been dropped by --cherry-pick
 807                 if test t = "$PRESERVE_MERGES"
 808                 then
 809                         mkdir "$DROPPED"
 810                         # Save all non-cherry-picked changes
 811                         git rev-list $REVISIONS --left-right --cherry-pick | \
 812                                 sed -n "s/^>//p" > "$DOTEST"/not-cherry-picks
 813                         # Now all commits and note which ones are missing in
 814                         # not-cherry-picks and hence being dropped
 815                         git rev-list $REVISIONS |
 816                         while read rev
 817                         do
 818                                 if test -f "$REWRITTEN"/$rev -a "$(sane_grep "$rev" "$DOTEST"/not-cherry-picks)" = ""
 819                                 then
 820                                         # Use -f2 because if rev-list is telling us this commit is
 821                                         # not worthwhile, we don't want to track its multiple heads,
 822                                         # just the history of its first-parent for others that will
 823                                         # be rebasing on top of it
 824                                         git rev-list --parents -1 $rev | cut -d' ' -s -f2 > "$DROPPED"/$rev
 825                                         short=$(git rev-list -1 --abbrev-commit --abbrev=7 $rev)
 826                                         sane_grep -v "^[a-z][a-z]* $short" <"$TODO" > "${TODO}2" ; mv "${TODO}2" "$TODO"
 827                                         rm "$REWRITTEN"/$rev
 828                                 fi
 829                         done
 830                 fi
 831
 832                 test -s "$TODO" || echo noop >> "$TODO"
 833                 cat >> "$TODO" << EOF
 834
 835 # Rebase $SHORTREVISIONS onto $SHORTONTO
 836 #
 837 # Commands:
 838 #  p, pick = use commit
 839 #  r, reword = use commit, but edit the commit message
 840 #  e, edit = use commit, but stop for amending
 841 #  s, squash = use commit, but meld into previous commit
 842 #  f, fixup = like "squash", but discard this commit's log message
 843 #
 844 # If you remove a line here THAT COMMIT WILL BE LOST.
 845 # However, if you remove everything, the rebase will be aborted.
 846 #
 847 EOF
 848
 849                 has_action "$TODO" ||
 850                         die_abort "Nothing to do"
 851
 852                 cp "$TODO" "$TODO".backup
 853                 git_editor "$TODO" ||
 854                         die "Could not execute editor"
 855
 856                 has_action "$TODO" ||
 857                         die_abort "Nothing to do"
 858
 859                 test -d "$REWRITTEN" || skip_unnecessary_picks
 860
 861                 git update-ref ORIG_HEAD $HEAD
 862                 output git checkout $ONTO && do_rest
 863                 ;;
 864         esac
 865         shift
 866 done