git-rebase--interactive.shon commit rebase -i: Use symbolic constant $MSG consistently (bdb011a)
   1#!/bin/sh
   2#
   3# Copyright (c) 2006 Johannes E. Schindelin
   4
   5# SHORT DESCRIPTION
   6#
   7# This script makes it easy to fix up commits in the middle of a series,
   8# and rearrange commits.
   9#
  10# The original idea comes from Eric W. Biederman, in
  11# http://article.gmane.org/gmane.comp.version-control.git/22407
  12
  13OPTIONS_KEEPDASHDASH=
  14OPTIONS_SPEC="\
  15git-rebase [-i] [options] [--] <upstream> [<branch>]
  16git-rebase [-i] (--continue | --abort | --skip)
  17--
  18 Available options are
  19v,verbose          display a diffstat of what changed upstream
  20onto=              rebase onto given branch instead of upstream
  21p,preserve-merges  try to recreate merges instead of ignoring them
  22s,strategy=        use the given merge strategy
  23m,merge            always used (no-op)
  24i,interactive      always used (no-op)
  25 Actions:
  26continue           continue rebasing process
  27abort              abort rebasing process and restore original branch
  28skip               skip current patch and continue rebasing process
  29no-verify          override pre-rebase hook from stopping the operation
  30root               rebase all reachable commmits up to the root(s)
  31"
  32
  33. git-sh-setup
  34require_work_tree
  35
  36DOTEST="$GIT_DIR/rebase-merge"
  37TODO="$DOTEST"/git-rebase-todo
  38DONE="$DOTEST"/done
  39MSG="$DOTEST"/message
  40SQUASH_MSG="$DOTEST"/message-squash
  41REWRITTEN="$DOTEST"/rewritten
  42DROPPED="$DOTEST"/dropped
  43PRESERVE_MERGES=
  44STRATEGY=
  45ONTO=
  46VERBOSE=
  47OK_TO_SKIP_PRE_REBASE=
  48REBASE_ROOT=
  49
  50GIT_CHERRY_PICK_HELP="  After resolving the conflicts,
  51mark the corrected paths with 'git add <paths>', and
  52run 'git rebase --continue'"
  53export GIT_CHERRY_PICK_HELP
  54
  55warn () {
  56        echo "$*" >&2
  57}
  58
  59output () {
  60        case "$VERBOSE" in
  61        '')
  62                output=$("$@" 2>&1 )
  63                status=$?
  64                test $status != 0 && printf "%s\n" "$output"
  65                return $status
  66                ;;
  67        *)
  68                "$@"
  69                ;;
  70        esac
  71}
  72
  73run_pre_rebase_hook () {
  74        if test -z "$OK_TO_SKIP_PRE_REBASE" &&
  75           test -x "$GIT_DIR/hooks/pre-rebase"
  76        then
  77                "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
  78                        echo >&2 "The pre-rebase hook refused to rebase."
  79                        exit 1
  80                }
  81        fi
  82}
  83
  84require_clean_work_tree () {
  85        # test if working tree is dirty
  86        git rev-parse --verify HEAD > /dev/null &&
  87        git update-index --ignore-submodules --refresh &&
  88        git diff-files --quiet --ignore-submodules &&
  89        git diff-index --cached --quiet HEAD --ignore-submodules -- ||
  90        die "Working tree is dirty"
  91}
  92
  93ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
  94
  95comment_for_reflog () {
  96        case "$ORIG_REFLOG_ACTION" in
  97        ''|rebase*)
  98                GIT_REFLOG_ACTION="rebase -i ($1)"
  99                export GIT_REFLOG_ACTION
 100                ;;
 101        esac
 102}
 103
 104last_count=
 105mark_action_done () {
 106        sed -e 1q < "$TODO" >> "$DONE"
 107        sed -e 1d < "$TODO" >> "$TODO".new
 108        mv -f "$TODO".new "$TODO"
 109        count=$(sane_grep -c '^[^#]' < "$DONE")
 110        total=$(($count+$(sane_grep -c '^[^#]' < "$TODO")))
 111        if test "$last_count" != "$count"
 112        then
 113                last_count=$count
 114                printf "Rebasing (%d/%d)\r" $count $total
 115                test -z "$VERBOSE" || echo
 116        fi
 117}
 118
 119make_patch () {
 120        sha1_and_parents="$(git rev-list --parents -1 "$1")"
 121        case "$sha1_and_parents" in
 122        ?*' '?*' '?*)
 123                git diff --cc $sha1_and_parents
 124                ;;
 125        ?*' '?*)
 126                git diff-tree -p "$1^!"
 127                ;;
 128        *)
 129                echo "Root commit"
 130                ;;
 131        esac > "$DOTEST"/patch
 132        test -f "$MSG" ||
 133                git cat-file commit "$1" | sed "1,/^$/d" > "$MSG"
 134        test -f "$DOTEST"/author-script ||
 135                get_author_ident_from_commit "$1" > "$DOTEST"/author-script
 136}
 137
 138die_with_patch () {
 139        make_patch "$1"
 140        git rerere
 141        die "$2"
 142}
 143
 144die_abort () {
 145        rm -rf "$DOTEST"
 146        die "$1"
 147}
 148
 149has_action () {
 150        sane_grep '^[^#]' "$1" >/dev/null
 151}
 152
 153pick_one () {
 154        no_ff=
 155        case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
 156        output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
 157        test -d "$REWRITTEN" &&
 158                pick_one_preserving_merges "$@" && return
 159        if test -n "$REBASE_ROOT"
 160        then
 161                output git cherry-pick "$@"
 162                return
 163        fi
 164        parent_sha1=$(git rev-parse --verify $sha1^) ||
 165                die "Could not get the parent of $sha1"
 166        current_sha1=$(git rev-parse --verify HEAD)
 167        if test -z "$no_ff" -a "$current_sha1" = "$parent_sha1"
 168        then
 169                output git reset --hard $sha1
 170                output warn Fast-forward to $(git rev-parse --short $sha1)
 171        else
 172                output git cherry-pick "$@"
 173        fi
 174}
 175
 176pick_one_preserving_merges () {
 177        fast_forward=t
 178        case "$1" in
 179        -n)
 180                fast_forward=f
 181                sha1=$2
 182                ;;
 183        *)
 184                sha1=$1
 185                ;;
 186        esac
 187        sha1=$(git rev-parse $sha1)
 188
 189        if test -f "$DOTEST"/current-commit
 190        then
 191                if test "$fast_forward" = t
 192                then
 193                        cat "$DOTEST"/current-commit | while read current_commit
 194                        do
 195                                git rev-parse HEAD > "$REWRITTEN"/$current_commit
 196                        done
 197                        rm "$DOTEST"/current-commit ||
 198                        die "Cannot write current commit's replacement sha1"
 199                fi
 200        fi
 201
 202        echo $sha1 >> "$DOTEST"/current-commit
 203
 204        # rewrite parents; if none were rewritten, we can fast-forward.
 205        new_parents=
 206        pend=" $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)"
 207        if test "$pend" = " "
 208        then
 209                pend=" root"
 210        fi
 211        while [ "$pend" != "" ]
 212        do
 213                p=$(expr "$pend" : ' \([^ ]*\)')
 214                pend="${pend# $p}"
 215
 216                if test -f "$REWRITTEN"/$p
 217                then
 218                        new_p=$(cat "$REWRITTEN"/$p)
 219
 220                        # If the todo reordered commits, and our parent is marked for
 221                        # rewriting, but hasn't been gotten to yet, assume the user meant to
 222                        # drop it on top of the current HEAD
 223                        if test -z "$new_p"
 224                        then
 225                                new_p=$(git rev-parse HEAD)
 226                        fi
 227
 228                        test $p != $new_p && fast_forward=f
 229                        case "$new_parents" in
 230                        *$new_p*)
 231                                ;; # do nothing; that parent is already there
 232                        *)
 233                                new_parents="$new_parents $new_p"
 234                                ;;
 235                        esac
 236                else
 237                        if test -f "$DROPPED"/$p
 238                        then
 239                                fast_forward=f
 240                                replacement="$(cat "$DROPPED"/$p)"
 241                                test -z "$replacement" && replacement=root
 242                                pend=" $replacement$pend"
 243                        else
 244                                new_parents="$new_parents $p"
 245                        fi
 246                fi
 247        done
 248        case $fast_forward in
 249        t)
 250                output warn "Fast-forward to $sha1"
 251                output git reset --hard $sha1 ||
 252                        die "Cannot fast-forward to $sha1"
 253                ;;
 254        f)
 255                first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
 256
 257                if [ "$1" != "-n" ]
 258                then
 259                        # detach HEAD to current parent
 260                        output git checkout $first_parent 2> /dev/null ||
 261                                die "Cannot move HEAD to $first_parent"
 262                fi
 263
 264                case "$new_parents" in
 265                ' '*' '*)
 266                        test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
 267
 268                        # redo merge
 269                        author_script=$(get_author_ident_from_commit $sha1)
 270                        eval "$author_script"
 271                        msg="$(git cat-file commit $sha1 | sed -e '1,/^$/d')"
 272                        # No point in merging the first parent, that's HEAD
 273                        new_parents=${new_parents# $first_parent}
 274                        if ! GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
 275                                GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
 276                                GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
 277                                output git merge $STRATEGY -m "$msg" \
 278                                        $new_parents
 279                        then
 280                                printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
 281                                die_with_patch $sha1 "Error redoing merge $sha1"
 282                        fi
 283                        ;;
 284                *)
 285                        output git cherry-pick "$@" ||
 286                                die_with_patch $sha1 "Could not pick $sha1"
 287                        ;;
 288                esac
 289                ;;
 290        esac
 291}
 292
 293nth_string () {
 294        case "$1" in
 295        *1[0-9]|*[04-9]) echo "$1"th;;
 296        *1) echo "$1"st;;
 297        *2) echo "$1"nd;;
 298        *3) echo "$1"rd;;
 299        esac
 300}
 301
 302make_squash_message () {
 303        if test -f "$SQUASH_MSG"; then
 304                # We want to be careful about matching only the commit
 305                # message comment lines generated by this function.
 306                # "[snrt][tdh]" matches the nth_string endings.
 307                COUNT=$(($(sed -n "s/^# Th[^0-9]*\([1-9][0-9]*\)[snrt][tdh] commit message.*:/\1/p" \
 308                        < "$SQUASH_MSG" | sed -ne '$p')+1))
 309                echo "# This is a combination of $COUNT commits."
 310                sed -e 1d -e '2,/^./{
 311                        /^$/d
 312                }' <"$SQUASH_MSG"
 313        else
 314                COUNT=2
 315                echo "# This is a combination of two commits."
 316                echo "# The first commit's message is:"
 317                echo
 318                git cat-file commit HEAD | sed -e '1,/^$/d'
 319        fi
 320        case $1 in
 321        squash)
 322                echo
 323                echo "# This is the $(nth_string $COUNT) commit message:"
 324                echo
 325                git cat-file commit $2 | sed -e '1,/^$/d'
 326                ;;
 327        fixup)
 328                echo
 329                echo "# The $(nth_string $COUNT) commit message will be skipped:"
 330                echo
 331                # Comment the lines of the commit message out using
 332                # "#    " rather than "# " to make them less likely to
 333                # confuse the sed regexp above.
 334                git cat-file commit $2 | sed -e '1,/^$/d' -e 's/^/#     /'
 335                ;;
 336        esac
 337}
 338
 339peek_next_command () {
 340        sed -n -e "/^#/d" -e "/^$/d" -e "s/ .*//p" -e "q" < "$TODO"
 341}
 342
 343do_next () {
 344        rm -f "$MSG" "$DOTEST"/author-script \
 345                "$DOTEST"/amend || exit
 346        read command sha1 rest < "$TODO"
 347        case "$command" in
 348        '#'*|''|noop)
 349                mark_action_done
 350                ;;
 351        pick|p)
 352                comment_for_reflog pick
 353
 354                mark_action_done
 355                pick_one $sha1 ||
 356                        die_with_patch $sha1 "Could not apply $sha1... $rest"
 357                ;;
 358        reword|r)
 359                comment_for_reflog reword
 360
 361                mark_action_done
 362                pick_one $sha1 ||
 363                        die_with_patch $sha1 "Could not apply $sha1... $rest"
 364                git commit --amend
 365                ;;
 366        edit|e)
 367                comment_for_reflog edit
 368
 369                mark_action_done
 370                pick_one $sha1 ||
 371                        die_with_patch $sha1 "Could not apply $sha1... $rest"
 372                make_patch $sha1
 373                git rev-parse --verify HEAD > "$DOTEST"/amend
 374                warn "Stopped at $sha1... $rest"
 375                warn "You can amend the commit now, with"
 376                warn
 377                warn "  git commit --amend"
 378                warn
 379                warn "Once you are satisfied with your changes, run"
 380                warn
 381                warn "  git rebase --continue"
 382                warn
 383                exit 0
 384                ;;
 385        squash|s|fixup|f)
 386                case "$command" in
 387                squash|s)
 388                        squash_style=squash
 389                        ;;
 390                fixup|f)
 391                        squash_style=fixup
 392                        ;;
 393                esac
 394                comment_for_reflog $squash_style
 395
 396                test -f "$DONE" && has_action "$DONE" ||
 397                        die "Cannot '$squash_style' without a previous commit"
 398
 399                mark_action_done
 400                make_squash_message $squash_style $sha1 > "$MSG"
 401                failed=f
 402                author_script=$(get_author_ident_from_commit HEAD)
 403                output git reset --soft HEAD^
 404                pick_one -n $sha1 || failed=t
 405                case "$(peek_next_command)" in
 406                squash|s|fixup|f)
 407                        USE_OUTPUT=output
 408                        MSG_OPT=-F
 409                        EDIT_OR_FILE="$MSG"
 410                        cp "$MSG" "$SQUASH_MSG"
 411                        ;;
 412                *)
 413                        USE_OUTPUT=
 414                        MSG_OPT=
 415                        EDIT_OR_FILE=-e
 416                        rm -f "$SQUASH_MSG" || exit
 417                        cp "$MSG" "$GIT_DIR"/SQUASH_MSG
 418                        rm -f "$GIT_DIR"/MERGE_MSG || exit
 419                        ;;
 420                esac
 421                echo "$author_script" > "$DOTEST"/author-script
 422                if test $failed = f
 423                then
 424                        # This is like --amend, but with a different message
 425                        eval "$author_script"
 426                        GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
 427                        GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
 428                        GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
 429                        $USE_OUTPUT git commit --no-verify \
 430                                $MSG_OPT "$EDIT_OR_FILE" || failed=t
 431                fi
 432                if test $failed = t
 433                then
 434                        cp "$MSG" "$GIT_DIR"/MERGE_MSG
 435                        warn
 436                        warn "Could not apply $sha1... $rest"
 437                        die_with_patch $sha1 ""
 438                fi
 439                ;;
 440        *)
 441                warn "Unknown command: $command $sha1 $rest"
 442                if git rev-parse --verify -q "$sha1" >/dev/null
 443                then
 444                        die_with_patch $sha1 "Please fix this in the file $TODO."
 445                else
 446                        die "Please fix this in the file $TODO."
 447                fi
 448                ;;
 449        esac
 450        test -s "$TODO" && return
 451
 452        comment_for_reflog finish &&
 453        HEADNAME=$(cat "$DOTEST"/head-name) &&
 454        OLDHEAD=$(cat "$DOTEST"/head) &&
 455        SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
 456        NEWHEAD=$(git rev-parse HEAD) &&
 457        case $HEADNAME in
 458        refs/*)
 459                message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO" &&
 460                git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
 461                git symbolic-ref HEAD $HEADNAME
 462                ;;
 463        esac && {
 464                test ! -f "$DOTEST"/verbose ||
 465                        git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
 466        } &&
 467        rm -rf "$DOTEST" &&
 468        git gc --auto &&
 469        warn "Successfully rebased and updated $HEADNAME."
 470
 471        exit
 472}
 473
 474do_rest () {
 475        while :
 476        do
 477                do_next
 478        done
 479}
 480
 481# skip picking commits whose parents are unchanged
 482skip_unnecessary_picks () {
 483        fd=3
 484        while read command sha1 rest
 485        do
 486                # fd=3 means we skip the command
 487                case "$fd,$command,$(git rev-parse --verify --quiet $sha1^)" in
 488                3,pick,"$ONTO"*|3,p,"$ONTO"*)
 489                        # pick a commit whose parent is current $ONTO -> skip
 490                        ONTO=$sha1
 491                        ;;
 492                3,#*|3,,*)
 493                        # copy comments
 494                        ;;
 495                *)
 496                        fd=1
 497                        ;;
 498                esac
 499                echo "$command${sha1:+ }$sha1${rest:+ }$rest" >&$fd
 500        done <"$TODO" >"$TODO.new" 3>>"$DONE" &&
 501        mv -f "$TODO".new "$TODO" ||
 502        die "Could not skip unnecessary pick commands"
 503}
 504
 505# check if no other options are set
 506is_standalone () {
 507        test $# -eq 2 -a "$2" = '--' &&
 508        test -z "$ONTO" &&
 509        test -z "$PRESERVE_MERGES" &&
 510        test -z "$STRATEGY" &&
 511        test -z "$VERBOSE"
 512}
 513
 514get_saved_options () {
 515        test -d "$REWRITTEN" && PRESERVE_MERGES=t
 516        test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
 517        test -f "$DOTEST"/verbose && VERBOSE=t
 518        test -f "$DOTEST"/rebase-root && REBASE_ROOT=t
 519}
 520
 521while test $# != 0
 522do
 523        case "$1" in
 524        --no-verify)
 525                OK_TO_SKIP_PRE_REBASE=yes
 526                ;;
 527        --verify)
 528                ;;
 529        --continue)
 530                is_standalone "$@" || usage
 531                get_saved_options
 532                comment_for_reflog continue
 533
 534                test -d "$DOTEST" || die "No interactive rebase running"
 535
 536                # Sanity check
 537                git rev-parse --verify HEAD >/dev/null ||
 538                        die "Cannot read HEAD"
 539                git update-index --ignore-submodules --refresh &&
 540                        git diff-files --quiet --ignore-submodules ||
 541                        die "Working tree is dirty"
 542
 543                # do we have anything to commit?
 544                if git diff-index --cached --quiet --ignore-submodules HEAD --
 545                then
 546                        : Nothing to commit -- skip this
 547                else
 548                        . "$DOTEST"/author-script ||
 549                                die "Cannot find the author identity"
 550                        amend=
 551                        if test -f "$DOTEST"/amend
 552                        then
 553                                amend=$(git rev-parse --verify HEAD)
 554                                test "$amend" = $(cat "$DOTEST"/amend) ||
 555                                die "\
 556You have uncommitted changes in your working tree. Please, commit them
 557first and then run 'git rebase --continue' again."
 558                                git reset --soft HEAD^ ||
 559                                die "Cannot rewind the HEAD"
 560                        fi
 561                        export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE &&
 562                        git commit --no-verify -F "$MSG" -e || {
 563                                test -n "$amend" && git reset --soft $amend
 564                                die "Could not commit staged changes."
 565                        }
 566                fi
 567
 568                require_clean_work_tree
 569                do_rest
 570                ;;
 571        --abort)
 572                is_standalone "$@" || usage
 573                get_saved_options
 574                comment_for_reflog abort
 575
 576                git rerere clear
 577                test -d "$DOTEST" || die "No interactive rebase running"
 578
 579                HEADNAME=$(cat "$DOTEST"/head-name)
 580                HEAD=$(cat "$DOTEST"/head)
 581                case $HEADNAME in
 582                refs/*)
 583                        git symbolic-ref HEAD $HEADNAME
 584                        ;;
 585                esac &&
 586                output git reset --hard $HEAD &&
 587                rm -rf "$DOTEST"
 588                exit
 589                ;;
 590        --skip)
 591                is_standalone "$@" || usage
 592                get_saved_options
 593                comment_for_reflog skip
 594
 595                git rerere clear
 596                test -d "$DOTEST" || die "No interactive rebase running"
 597
 598                output git reset --hard && do_rest
 599                ;;
 600        -s)
 601                case "$#,$1" in
 602                *,*=*)
 603                        STRATEGY="-s "$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
 604                1,*)
 605                        usage ;;
 606                *)
 607                        STRATEGY="-s $2"
 608                        shift ;;
 609                esac
 610                ;;
 611        -m)
 612                # we use merge anyway
 613                ;;
 614        -v)
 615                VERBOSE=t
 616                ;;
 617        -p)
 618                PRESERVE_MERGES=t
 619                ;;
 620        -i)
 621                # yeah, we know
 622                ;;
 623        --root)
 624                REBASE_ROOT=t
 625                ;;
 626        --onto)
 627                shift
 628                ONTO=$(git rev-parse --verify "$1") ||
 629                        die "Does not point to a valid commit: $1"
 630                ;;
 631        --)
 632                shift
 633                test -z "$REBASE_ROOT" -a $# -ge 1 -a $# -le 2 ||
 634                test ! -z "$REBASE_ROOT" -a $# -le 1 || usage
 635                test -d "$DOTEST" &&
 636                        die "Interactive rebase already started"
 637
 638                git var GIT_COMMITTER_IDENT >/dev/null ||
 639                        die "You need to set your committer info first"
 640
 641                if test -z "$REBASE_ROOT"
 642                then
 643                        UPSTREAM_ARG="$1"
 644                        UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
 645                        test -z "$ONTO" && ONTO=$UPSTREAM
 646                        shift
 647                else
 648                        UPSTREAM=
 649                        UPSTREAM_ARG=--root
 650                        test -z "$ONTO" &&
 651                                die "You must specify --onto when using --root"
 652                fi
 653                run_pre_rebase_hook "$UPSTREAM_ARG" "$@"
 654
 655                comment_for_reflog start
 656
 657                require_clean_work_tree
 658
 659                if test ! -z "$1"
 660                then
 661                        output git show-ref --verify --quiet "refs/heads/$1" ||
 662                                die "Invalid branchname: $1"
 663                        output git checkout "$1" ||
 664                                die "Could not checkout $1"
 665                fi
 666
 667                HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
 668                mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
 669
 670                : > "$DOTEST"/interactive || die "Could not mark as interactive"
 671                git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
 672                        echo "detached HEAD" > "$DOTEST"/head-name
 673
 674                echo $HEAD > "$DOTEST"/head
 675                case "$REBASE_ROOT" in
 676                '')
 677                        rm -f "$DOTEST"/rebase-root ;;
 678                *)
 679                        : >"$DOTEST"/rebase-root ;;
 680                esac
 681                echo $ONTO > "$DOTEST"/onto
 682                test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
 683                test t = "$VERBOSE" && : > "$DOTEST"/verbose
 684                if test t = "$PRESERVE_MERGES"
 685                then
 686                        # $REWRITTEN contains files for each commit that is
 687                        # reachable by at least one merge base of $HEAD and
 688                        # $UPSTREAM. They are not necessarily rewritten, but
 689                        # their children might be.
 690                        # This ensures that commits on merged, but otherwise
 691                        # unrelated side branches are left alone. (Think "X"
 692                        # in the man page's example.)
 693                        if test -z "$REBASE_ROOT"
 694                        then
 695                                mkdir "$REWRITTEN" &&
 696                                for c in $(git merge-base --all $HEAD $UPSTREAM)
 697                                do
 698                                        echo $ONTO > "$REWRITTEN"/$c ||
 699                                                die "Could not init rewritten commits"
 700                                done
 701                        else
 702                                mkdir "$REWRITTEN" &&
 703                                echo $ONTO > "$REWRITTEN"/root ||
 704                                        die "Could not init rewritten commits"
 705                        fi
 706                        # No cherry-pick because our first pass is to determine
 707                        # parents to rewrite and skipping dropped commits would
 708                        # prematurely end our probe
 709                        MERGES_OPTION=
 710                        first_after_upstream="$(git rev-list --reverse --first-parent $UPSTREAM..$HEAD | head -n 1)"
 711                else
 712                        MERGES_OPTION="--no-merges --cherry-pick"
 713                fi
 714
 715                SHORTHEAD=$(git rev-parse --short $HEAD)
 716                SHORTONTO=$(git rev-parse --short $ONTO)
 717                if test -z "$REBASE_ROOT"
 718                        # this is now equivalent to ! -z "$UPSTREAM"
 719                then
 720                        SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
 721                        REVISIONS=$UPSTREAM...$HEAD
 722                        SHORTREVISIONS=$SHORTUPSTREAM..$SHORTHEAD
 723                else
 724                        REVISIONS=$ONTO...$HEAD
 725                        SHORTREVISIONS=$SHORTHEAD
 726                fi
 727                git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
 728                        --abbrev=7 --reverse --left-right --topo-order \
 729                        $REVISIONS | \
 730                        sed -n "s/^>//p" | while read shortsha1 rest
 731                do
 732                        if test t != "$PRESERVE_MERGES"
 733                        then
 734                                echo "pick $shortsha1 $rest" >> "$TODO"
 735                        else
 736                                sha1=$(git rev-parse $shortsha1)
 737                                if test -z "$REBASE_ROOT"
 738                                then
 739                                        preserve=t
 740                                        for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)
 741                                        do
 742                                                if test -f "$REWRITTEN"/$p -a \( $p != $ONTO -o $sha1 = $first_after_upstream \)
 743                                                then
 744                                                        preserve=f
 745                                                fi
 746                                        done
 747                                else
 748                                        preserve=f
 749                                fi
 750                                if test f = "$preserve"
 751                                then
 752                                        touch "$REWRITTEN"/$sha1
 753                                        echo "pick $shortsha1 $rest" >> "$TODO"
 754                                fi
 755                        fi
 756                done
 757
 758                # Watch for commits that been dropped by --cherry-pick
 759                if test t = "$PRESERVE_MERGES"
 760                then
 761                        mkdir "$DROPPED"
 762                        # Save all non-cherry-picked changes
 763                        git rev-list $REVISIONS --left-right --cherry-pick | \
 764                                sed -n "s/^>//p" > "$DOTEST"/not-cherry-picks
 765                        # Now all commits and note which ones are missing in
 766                        # not-cherry-picks and hence being dropped
 767                        git rev-list $REVISIONS |
 768                        while read rev
 769                        do
 770                                if test -f "$REWRITTEN"/$rev -a "$(sane_grep "$rev" "$DOTEST"/not-cherry-picks)" = ""
 771                                then
 772                                        # Use -f2 because if rev-list is telling us this commit is
 773                                        # not worthwhile, we don't want to track its multiple heads,
 774                                        # just the history of its first-parent for others that will
 775                                        # be rebasing on top of it
 776                                        git rev-list --parents -1 $rev | cut -d' ' -s -f2 > "$DROPPED"/$rev
 777                                        short=$(git rev-list -1 --abbrev-commit --abbrev=7 $rev)
 778                                        sane_grep -v "^[a-z][a-z]* $short" <"$TODO" > "${TODO}2" ; mv "${TODO}2" "$TODO"
 779                                        rm "$REWRITTEN"/$rev
 780                                fi
 781                        done
 782                fi
 783
 784                test -s "$TODO" || echo noop >> "$TODO"
 785                cat >> "$TODO" << EOF
 786
 787# Rebase $SHORTREVISIONS onto $SHORTONTO
 788#
 789# Commands:
 790#  p, pick = use commit
 791#  r, reword = use commit, but edit the commit message
 792#  e, edit = use commit, but stop for amending
 793#  s, squash = use commit, but meld into previous commit
 794#  f, fixup = like "squash", but discard this commit's log message
 795#
 796# If you remove a line here THAT COMMIT WILL BE LOST.
 797# However, if you remove everything, the rebase will be aborted.
 798#
 799EOF
 800
 801                has_action "$TODO" ||
 802                        die_abort "Nothing to do"
 803
 804                cp "$TODO" "$TODO".backup
 805                git_editor "$TODO" ||
 806                        die "Could not execute editor"
 807
 808                has_action "$TODO" ||
 809                        die_abort "Nothing to do"
 810
 811                test -d "$REWRITTEN" || skip_unnecessary_picks
 812
 813                git update-ref ORIG_HEAD $HEAD
 814                output git checkout $ONTO && do_rest
 815                ;;
 816        esac
 817        shift
 818done