efa83f61348f2603872d01a48cc9ae2ffaadc1ff
   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
  13USAGE='(--continue | --abort | --skip | [--preserve-merges] [--verbose]
  14        [--onto <branch>] <upstream> [<branch>])'
  15
  16. git-sh-setup
  17require_work_tree
  18
  19DOTEST="$GIT_DIR/.dotest-merge"
  20TODO="$DOTEST"/git-rebase-todo
  21DONE="$DOTEST"/done
  22MSG="$DOTEST"/message
  23SQUASH_MSG="$DOTEST"/message-squash
  24REWRITTEN="$DOTEST"/rewritten
  25PRESERVE_MERGES=
  26STRATEGY=
  27VERBOSE=
  28test -d "$REWRITTEN" && PRESERVE_MERGES=t
  29test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
  30test -f "$DOTEST"/verbose && VERBOSE=t
  31
  32warn () {
  33        echo "$*" >&2
  34}
  35
  36output () {
  37        case "$VERBOSE" in
  38        '')
  39                "$@" > "$DOTEST"/output 2>&1
  40                status=$?
  41                test $status != 0 &&
  42                        cat "$DOTEST"/output
  43                return $status
  44                ;;
  45        *)
  46                "$@"
  47                ;;
  48        esac
  49}
  50
  51require_clean_work_tree () {
  52        # test if working tree is dirty
  53        git rev-parse --verify HEAD > /dev/null &&
  54        git update-index --refresh &&
  55        git diff-files --quiet &&
  56        git diff-index --cached --quiet HEAD ||
  57        die "Working tree is dirty"
  58}
  59
  60ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
  61
  62comment_for_reflog () {
  63        case "$ORIG_REFLOG_ACTION" in
  64        ''|rebase*)
  65                GIT_REFLOG_ACTION="rebase -i ($1)"
  66                export GIT_REFLOG_ACTION
  67                ;;
  68        esac
  69}
  70
  71mark_action_done () {
  72        sed -e 1q < "$TODO" >> "$DONE"
  73        sed -e 1d < "$TODO" >> "$TODO".new
  74        mv -f "$TODO".new "$TODO"
  75        count=$(($(grep -ve '^$' -e '^#' < "$DONE" | wc -l)))
  76        total=$(($count+$(grep -ve '^$' -e '^#' < "$TODO" | wc -l)))
  77        printf "Rebasing (%d/%d)\r" $count $total
  78        test -z "$VERBOSE" || echo
  79}
  80
  81make_patch () {
  82        parent_sha1=$(git rev-parse --verify "$1"^) ||
  83                die "Cannot get patch for $1^"
  84        git diff "$parent_sha1".."$1" > "$DOTEST"/patch
  85        test -f "$DOTEST"/message ||
  86                git cat-file commit "$1" | sed "1,/^$/d" > "$DOTEST"/message
  87        test -f "$DOTEST"/author-script ||
  88                get_author_ident_from_commit "$1" > "$DOTEST"/author-script
  89}
  90
  91die_with_patch () {
  92        make_patch "$1"
  93        die "$2"
  94}
  95
  96die_abort () {
  97        rm -rf "$DOTEST"
  98        die "$1"
  99}
 100
 101has_action () {
 102        grep -vqe '^$' -e '^#' "$1"
 103}
 104
 105pick_one () {
 106        no_ff=
 107        case "$1" in -n) sha1=$2; no_ff=t ;; *) sha1=$1 ;; esac
 108        output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
 109        test -d "$REWRITTEN" &&
 110                pick_one_preserving_merges "$@" && return
 111        parent_sha1=$(git rev-parse --verify $sha1^) ||
 112                die "Could not get the parent of $sha1"
 113        current_sha1=$(git rev-parse --verify HEAD)
 114        if test $no_ff$current_sha1 = $parent_sha1; then
 115                output git reset --hard $sha1
 116                test "a$1" = a-n && output git reset --soft $current_sha1
 117                sha1=$(git rev-parse --short $sha1)
 118                output warn Fast forward to $sha1
 119        else
 120                output git cherry-pick $STRATEGY "$@"
 121        fi
 122}
 123
 124pick_one_preserving_merges () {
 125        case "$1" in -n) sha1=$2 ;; *) sha1=$1 ;; esac
 126        sha1=$(git rev-parse $sha1)
 127
 128        if test -f "$DOTEST"/current-commit
 129        then
 130                current_commit=$(cat "$DOTEST"/current-commit) &&
 131                git rev-parse HEAD > "$REWRITTEN"/$current_commit &&
 132                rm "$DOTEST"/current-commit ||
 133                die "Cannot write current commit's replacement sha1"
 134        fi
 135
 136        # rewrite parents; if none were rewritten, we can fast-forward.
 137        fast_forward=t
 138        preserve=t
 139        new_parents=
 140        for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -f2-)
 141        do
 142                if test -f "$REWRITTEN"/$p
 143                then
 144                        preserve=f
 145                        new_p=$(cat "$REWRITTEN"/$p)
 146                        test $p != $new_p && fast_forward=f
 147                        case "$new_parents" in
 148                        *$new_p*)
 149                                ;; # do nothing; that parent is already there
 150                        *)
 151                                new_parents="$new_parents $new_p"
 152                                ;;
 153                        esac
 154                fi
 155        done
 156        case $fast_forward in
 157        t)
 158                output warn "Fast forward to $sha1"
 159                test $preserve = f || echo $sha1 > "$REWRITTEN"/$sha1
 160                ;;
 161        f)
 162                test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
 163
 164                first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
 165                # detach HEAD to current parent
 166                output git checkout $first_parent 2> /dev/null ||
 167                        die "Cannot move HEAD to $first_parent"
 168
 169                echo $sha1 > "$DOTEST"/current-commit
 170                case "$new_parents" in
 171                ' '*' '*)
 172                        # redo merge
 173                        author_script=$(get_author_ident_from_commit $sha1)
 174                        eval "$author_script"
 175                        msg="$(git cat-file commit $sha1 | sed -e '1,/^$/d')"
 176                        # NEEDSWORK: give rerere a chance
 177                        if ! output git merge $STRATEGY -m "$msg" $new_parents
 178                        then
 179                                printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
 180                                die Error redoing merge $sha1
 181                        fi
 182                        ;;
 183                *)
 184                        output git cherry-pick $STRATEGY "$@" ||
 185                                die_with_patch $sha1 "Could not pick $sha1"
 186                        ;;
 187                esac
 188                ;;
 189        esac
 190}
 191
 192nth_string () {
 193        case "$1" in
 194        *1[0-9]|*[04-9]) echo "$1"th;;
 195        *1) echo "$1"st;;
 196        *2) echo "$1"nd;;
 197        *3) echo "$1"rd;;
 198        esac
 199}
 200
 201make_squash_message () {
 202        if test -f "$SQUASH_MSG"; then
 203                COUNT=$(($(sed -n "s/^# This is [^0-9]*\([1-9][0-9]*\).*/\1/p" \
 204                        < "$SQUASH_MSG" | tail -n 1)+1))
 205                echo "# This is a combination of $COUNT commits."
 206                sed -n "2,\$p" < "$SQUASH_MSG"
 207        else
 208                COUNT=2
 209                echo "# This is a combination of two commits."
 210                echo "# The first commit's message is:"
 211                echo
 212                git cat-file commit HEAD | sed -e '1,/^$/d'
 213                echo
 214        fi
 215        echo "# This is the $(nth_string $COUNT) commit message:"
 216        echo
 217        git cat-file commit $1 | sed -e '1,/^$/d'
 218}
 219
 220peek_next_command () {
 221        sed -n "1s/ .*$//p" < "$TODO"
 222}
 223
 224do_next () {
 225        rm -f "$DOTEST"/message "$DOTEST"/author-script \
 226                "$DOTEST"/amend || exit
 227        read command sha1 rest < "$TODO"
 228        case "$command" in
 229        '#'*|'')
 230                mark_action_done
 231                ;;
 232        pick)
 233                comment_for_reflog pick
 234
 235                mark_action_done
 236                pick_one $sha1 ||
 237                        die_with_patch $sha1 "Could not apply $sha1... $rest"
 238                ;;
 239        edit)
 240                comment_for_reflog edit
 241
 242                mark_action_done
 243                pick_one $sha1 ||
 244                        die_with_patch $sha1 "Could not apply $sha1... $rest"
 245                make_patch $sha1
 246                : > "$DOTEST"/amend
 247                warn
 248                warn "You can amend the commit now, with"
 249                warn
 250                warn "  git commit --amend"
 251                warn
 252                exit 0
 253                ;;
 254        squash)
 255                comment_for_reflog squash
 256
 257                has_action "$DONE" ||
 258                        die "Cannot 'squash' without a previous commit"
 259
 260                mark_action_done
 261                make_squash_message $sha1 > "$MSG"
 262                case "$(peek_next_command)" in
 263                squash)
 264                        EDIT_COMMIT=
 265                        USE_OUTPUT=output
 266                        cp "$MSG" "$SQUASH_MSG"
 267                        ;;
 268                *)
 269                        EDIT_COMMIT=-e
 270                        USE_OUTPUT=
 271                        rm -f "$SQUASH_MSG" || exit
 272                        ;;
 273                esac
 274
 275                failed=f
 276                output git reset --soft HEAD^
 277                pick_one -n $sha1 || failed=t
 278                author_script=$(get_author_ident_from_commit $sha1)
 279                echo "$author_script" > "$DOTEST"/author-script
 280                case $failed in
 281                f)
 282                        # This is like --amend, but with a different message
 283                        eval "$author_script"
 284                        export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
 285                        $USE_OUTPUT git commit -F "$MSG" $EDIT_COMMIT
 286                        ;;
 287                t)
 288                        cp "$MSG" "$GIT_DIR"/MERGE_MSG
 289                        warn
 290                        warn "Could not apply $sha1... $rest"
 291                        die_with_patch $sha1 ""
 292                        ;;
 293                esac
 294                ;;
 295        *)
 296                warn "Unknown command: $command $sha1 $rest"
 297                die_with_patch $sha1 "Please fix this in the file $TODO."
 298                ;;
 299        esac
 300        test -s "$TODO" && return
 301
 302        comment_for_reflog finish &&
 303        HEADNAME=$(cat "$DOTEST"/head-name) &&
 304        OLDHEAD=$(cat "$DOTEST"/head) &&
 305        SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
 306        if test -d "$REWRITTEN"
 307        then
 308                test -f "$DOTEST"/current-commit &&
 309                        current_commit=$(cat "$DOTEST"/current-commit) &&
 310                        git rev-parse HEAD > "$REWRITTEN"/$current_commit
 311                NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
 312        else
 313                NEWHEAD=$(git rev-parse HEAD)
 314        fi &&
 315        message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
 316        git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
 317        git symbolic-ref HEAD $HEADNAME && {
 318                test ! -f "$DOTEST"/verbose ||
 319                        git diff --stat $(cat "$DOTEST"/head)..HEAD
 320        } &&
 321        rm -rf "$DOTEST" &&
 322        warn "Successfully rebased and updated $HEADNAME."
 323
 324        exit
 325}
 326
 327do_rest () {
 328        while :
 329        do
 330                do_next
 331        done
 332}
 333
 334while test $# != 0
 335do
 336        case "$1" in
 337        --continue)
 338                comment_for_reflog continue
 339
 340                test -d "$DOTEST" || die "No interactive rebase running"
 341
 342                # commit if necessary
 343                git rev-parse --verify HEAD > /dev/null &&
 344                git update-index --refresh &&
 345                git diff-files --quiet &&
 346                ! git diff-index --cached --quiet HEAD &&
 347                . "$DOTEST"/author-script && {
 348                        test ! -f "$DOTEST"/amend || git reset --soft HEAD^
 349                } &&
 350                export GIT_AUTHOR_NAME GIT_AUTHOR_NAME GIT_AUTHOR_DATE &&
 351                git commit -F "$DOTEST"/message -e
 352
 353                require_clean_work_tree
 354                do_rest
 355                ;;
 356        --abort)
 357                comment_for_reflog abort
 358
 359                test -d "$DOTEST" || die "No interactive rebase running"
 360
 361                HEADNAME=$(cat "$DOTEST"/head-name)
 362                HEAD=$(cat "$DOTEST"/head)
 363                git symbolic-ref HEAD $HEADNAME &&
 364                output git reset --hard $HEAD &&
 365                rm -rf "$DOTEST"
 366                exit
 367                ;;
 368        --skip)
 369                comment_for_reflog skip
 370
 371                test -d "$DOTEST" || die "No interactive rebase running"
 372
 373                output git reset --hard && do_rest
 374                ;;
 375        -s|--strategy)
 376                shift
 377                case "$#,$1" in
 378                *,*=*)
 379                        STRATEGY="-s `expr "z$1" : 'z-[^=]*=\(.*\)'`" ;;
 380                1,*)
 381                        usage ;;
 382                *)
 383                        STRATEGY="-s $2"
 384                        shift ;;
 385                esac
 386                ;;
 387        --merge)
 388                # we use merge anyway
 389                ;;
 390        -C*)
 391                die "Interactive rebase uses merge, so $1 does not make sense"
 392                ;;
 393        -v|--verbose)
 394                VERBOSE=t
 395                ;;
 396        -p|--preserve-merges)
 397                PRESERVE_MERGES=t
 398                ;;
 399        -i|--interactive)
 400                # yeah, we know
 401                ;;
 402        ''|-h)
 403                usage
 404                ;;
 405        *)
 406                test -d "$DOTEST" &&
 407                        die "Interactive rebase already started"
 408
 409                git var GIT_COMMITTER_IDENT >/dev/null ||
 410                        die "You need to set your committer info first"
 411
 412                comment_for_reflog start
 413
 414                ONTO=
 415                case "$1" in
 416                --onto)
 417                        ONTO=$(git rev-parse --verify "$2") ||
 418                                die "Does not point to a valid commit: $2"
 419                        shift; shift
 420                        ;;
 421                esac
 422
 423                require_clean_work_tree
 424
 425                mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
 426                if test ! -z "$2"
 427                then
 428                        output git show-ref --verify --quiet "refs/heads/$2" ||
 429                                die "Invalid branchname: $2"
 430                        output git checkout "$2" ||
 431                                die "Could not checkout $2"
 432                fi
 433
 434                HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
 435                UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
 436
 437                test -z "$ONTO" && ONTO=$UPSTREAM
 438
 439                : > "$DOTEST"/interactive || die "Could not mark as interactive"
 440                git symbolic-ref HEAD > "$DOTEST"/head-name ||
 441                        die "Could not get HEAD"
 442
 443                echo $HEAD > "$DOTEST"/head
 444                echo $UPSTREAM > "$DOTEST"/upstream
 445                echo $ONTO > "$DOTEST"/onto
 446                test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
 447                test t = "$VERBOSE" && : > "$DOTEST"/verbose
 448                if test t = "$PRESERVE_MERGES"
 449                then
 450                        # $REWRITTEN contains files for each commit that is
 451                        # reachable by at least one merge base of $HEAD and
 452                        # $UPSTREAM. They are not necessarily rewritten, but
 453                        # their children might be.
 454                        # This ensures that commits on merged, but otherwise
 455                        # unrelated side branches are left alone. (Think "X"
 456                        # in the man page's example.)
 457                        mkdir "$REWRITTEN" &&
 458                        for c in $(git merge-base --all $HEAD $UPSTREAM)
 459                        do
 460                                echo $ONTO > "$REWRITTEN"/$c ||
 461                                        die "Could not init rewritten commits"
 462                        done
 463                        MERGES_OPTION=
 464                else
 465                        MERGES_OPTION=--no-merges
 466                fi
 467
 468                SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
 469                SHORTHEAD=$(git rev-parse --short $HEAD)
 470                SHORTONTO=$(git rev-parse --short $ONTO)
 471                cat > "$TODO" << EOF
 472# Rebasing $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
 473#
 474# Commands:
 475#  pick = use commit
 476#  edit = use commit, but stop for amending
 477#  squash = use commit, but meld into previous commit
 478#
 479# If you remove a line here THAT COMMIT WILL BE LOST.
 480#
 481EOF
 482                git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
 483                        --abbrev=7 --reverse --left-right --cherry-pick \
 484                        $UPSTREAM...$HEAD | \
 485                        sed -n "s/^>/pick /p" >> "$TODO"
 486
 487                has_action "$TODO" ||
 488                        die_abort "Nothing to do"
 489
 490                cp "$TODO" "$TODO".backup
 491                git_editor "$TODO" ||
 492                        die "Could not execute editor"
 493
 494                has_action "$TODO" ||
 495                        die_abort "Nothing to do"
 496
 497                output git checkout $ONTO && do_rest
 498                ;;
 499        esac
 500        shift
 501done