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