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 USAGE='(--continue | --abort | --skip | [--preserve-merges] [--verbose]
  14         [--onto <branch>] <upstream> [<branch>])'
  15
  16 OPTIONS_SPEC=
  17 . git-sh-setup
  18 require_work_tree
  19
  20 DOTEST="$GIT_DIR/.dotest-merge"
  21 TODO="$DOTEST"/git-rebase-todo
  22 DONE="$DOTEST"/done
  23 MSG="$DOTEST"/message
  24 SQUASH_MSG="$DOTEST"/message-squash
  25 REWRITTEN="$DOTEST"/rewritten
  26 PRESERVE_MERGES=
  27 STRATEGY=
  28 VERBOSE=
  29 test -d "$REWRITTEN" && PRESERVE_MERGES=t
  30 test -f "$DOTEST"/strategy && STRATEGY="$(cat "$DOTEST"/strategy)"
  31 test -f "$DOTEST"/verbose && VERBOSE=t
  32
  33 warn () {
  34         echo "$*" >&2
  35 }
  36
  37 output () {
  38         case "$VERBOSE" in
  39         '')
  40                 output=$("$@" 2>&1 )
  41                 status=$?
  42                 test $status != 0 && printf "%s\n" "$output"
  43                 return $status
  44                 ;;
  45         *)
  46                 "$@"
  47                 ;;
  48         esac
  49 }
  50
  51 require_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
  60 ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
  61
  62 comment_for_reflog () {
  63         case "$ORIG_REFLOG_ACTION" in
  64         ''|rebase*)
  65                 GIT_REFLOG_ACTION="rebase -i ($1)"
  66                 export GIT_REFLOG_ACTION
  67                 ;;
  68         esac
  69 }
  70
  71 mark_action_done () {
  72         sed -e 1q < "$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
  81 make_patch () {
  82         parent_sha1=$(git rev-parse --verify "$1"^) ||
  83                 die "Cannot get patch for $1^"
  84         git diff-tree -p "$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
  91 die_with_patch () {
  92         make_patch "$1"
  93         die "$2"
  94 }
  95
  96 die_abort () {
  97         rm -rf "$DOTEST"
  98         die "$1"
  99 }
 100
 101 has_action () {
 102         grep -vqe '^$' -e '^#' "$1"
 103 }
 104
 105 pick_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 $sha1
 119         else
 120                 output git cherry-pick "$@"
 121         fi
 122 }
 123
 124 pick_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                         # No point in merging the first parent, that's HEAD
 177                         new_parents=${new_parents# $first_parent}
 178                         # NEEDSWORK: give rerere a chance
 179                         if ! GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
 180                                 GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
 181                                 GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
 182                                 output git merge $STRATEGY -m "$msg" \
 183                                         $new_parents
 184                         then
 185                                 printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
 186                                 die Error redoing merge $sha1
 187                         fi
 188                         ;;
 189                 *)
 190                         output git cherry-pick "$@" ||
 191                                 die_with_patch $sha1 "Could not pick $sha1"
 192                         ;;
 193                 esac
 194                 ;;
 195         esac
 196 }
 197
 198 nth_string () {
 199         case "$1" in
 200         *1[0-9]|*[04-9]) echo "$1"th;;
 201         *1) echo "$1"st;;
 202         *2) echo "$1"nd;;
 203         *3) echo "$1"rd;;
 204         esac
 205 }
 206
 207 make_squash_message () {
 208         if test -f "$SQUASH_MSG"; then
 209                 COUNT=$(($(sed -n "s/^# This is [^0-9]*\([1-9][0-9]*\).*/\1/p" \
 210                         < "$SQUASH_MSG" | tail -n 1)+1))
 211                 echo "# This is a combination of $COUNT commits."
 212                 sed -n "2,\$p" < "$SQUASH_MSG"
 213         else
 214                 COUNT=2
 215                 echo "# This is a combination of two commits."
 216                 echo "# The first commit's message is:"
 217                 echo
 218                 git cat-file commit HEAD | sed -e '1,/^$/d'
 219                 echo
 220         fi
 221         echo "# This is the $(nth_string $COUNT) commit message:"
 222         echo
 223         git cat-file commit $1 | sed -e '1,/^$/d'
 224 }
 225
 226 peek_next_command () {
 227         sed -n "1s/ .*$//p" < "$TODO"
 228 }
 229
 230 do_next () {
 231         rm -f "$DOTEST"/message "$DOTEST"/author-script \
 232                 "$DOTEST"/amend || exit
 233         read command sha1 rest < "$TODO"
 234         case "$command" in
 235         '#'*|'')
 236                 mark_action_done
 237                 ;;
 238         pick|p)
 239                 comment_for_reflog pick
 240
 241                 mark_action_done
 242                 pick_one $sha1 ||
 243                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 244                 ;;
 245         edit|e)
 246                 comment_for_reflog edit
 247
 248                 mark_action_done
 249                 pick_one $sha1 ||
 250                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 251                 make_patch $sha1
 252                 : > "$DOTEST"/amend
 253                 warn
 254                 warn "You can amend the commit now, with"
 255                 warn
 256                 warn "  git commit --amend"
 257                 warn
 258                 exit 0
 259                 ;;
 260         squash|s)
 261                 comment_for_reflog squash
 262
 263                 has_action "$DONE" ||
 264                         die "Cannot 'squash' without a previous commit"
 265
 266                 mark_action_done
 267                 make_squash_message $sha1 > "$MSG"
 268                 case "$(peek_next_command)" in
 269                 squash|s)
 270                         EDIT_COMMIT=
 271                         USE_OUTPUT=output
 272                         cp "$MSG" "$SQUASH_MSG"
 273                         ;;
 274                 *)
 275                         EDIT_COMMIT=-e
 276                         USE_OUTPUT=
 277                         rm -f "$SQUASH_MSG" || exit
 278                         ;;
 279                 esac
 280
 281                 failed=f
 282                 author_script=$(get_author_ident_from_commit HEAD)
 283                 output git reset --soft HEAD^
 284                 pick_one -n $sha1 || failed=t
 285                 echo "$author_script" > "$DOTEST"/author-script
 286                 case $failed in
 287                 f)
 288                         # This is like --amend, but with a different message
 289                         eval "$author_script"
 290                         GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
 291                         GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
 292                         GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
 293                         $USE_OUTPUT git commit -F "$MSG" $EDIT_COMMIT
 294                         ;;
 295                 t)
 296                         cp "$MSG" "$GIT_DIR"/MERGE_MSG
 297                         warn
 298                         warn "Could not apply $sha1... $rest"
 299                         die_with_patch $sha1 ""
 300                         ;;
 301                 esac
 302                 ;;
 303         *)
 304                 warn "Unknown command: $command $sha1 $rest"
 305                 die_with_patch $sha1 "Please fix this in the file $TODO."
 306                 ;;
 307         esac
 308         test -s "$TODO" && return
 309
 310         comment_for_reflog finish &&
 311         HEADNAME=$(cat "$DOTEST"/head-name) &&
 312         OLDHEAD=$(cat "$DOTEST"/head) &&
 313         SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
 314         if test -d "$REWRITTEN"
 315         then
 316                 test -f "$DOTEST"/current-commit &&
 317                         current_commit=$(cat "$DOTEST"/current-commit) &&
 318                         git rev-parse HEAD > "$REWRITTEN"/$current_commit
 319                 NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
 320         else
 321                 NEWHEAD=$(git rev-parse HEAD)
 322         fi &&
 323         case $HEADNAME in
 324         refs/*)
 325                 message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
 326                 git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
 327                 git symbolic-ref HEAD $HEADNAME
 328                 ;;
 329         esac && {
 330                 test ! -f "$DOTEST"/verbose ||
 331                         git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
 332         } &&
 333         rm -rf "$DOTEST" &&
 334         git gc --auto &&
 335         warn "Successfully rebased and updated $HEADNAME."
 336
 337         exit
 338 }
 339
 340 do_rest () {
 341         while :
 342         do
 343                 do_next
 344         done
 345 }
 346
 347 while test $# != 0
 348 do
 349         case "$1" in
 350         --continue)
 351                 comment_for_reflog continue
 352
 353                 test -d "$DOTEST" || die "No interactive rebase running"
 354
 355                 # commit if necessary
 356                 git rev-parse --verify HEAD > /dev/null &&
 357                 git update-index --refresh &&
 358                 git diff-files --quiet &&
 359                 ! git diff-index --cached --quiet HEAD &&
 360                 . "$DOTEST"/author-script && {
 361                         test ! -f "$DOTEST"/amend || git reset --soft HEAD^
 362                 } &&
 363                 export GIT_AUTHOR_NAME GIT_AUTHOR_NAME GIT_AUTHOR_DATE &&
 364                 git commit -F "$DOTEST"/message -e
 365
 366                 require_clean_work_tree
 367                 do_rest
 368                 ;;
 369         --abort)
 370                 comment_for_reflog abort
 371
 372                 test -d "$DOTEST" || die "No interactive rebase running"
 373
 374                 HEADNAME=$(cat "$DOTEST"/head-name)
 375                 HEAD=$(cat "$DOTEST"/head)
 376                 case $HEADNAME in
 377                 refs/*)
 378                         git symbolic-ref HEAD $HEADNAME
 379                         ;;
 380                 esac &&
 381                 output git reset --hard $HEAD &&
 382                 rm -rf "$DOTEST"
 383                 exit
 384                 ;;
 385         --skip)
 386                 comment_for_reflog skip
 387
 388                 test -d "$DOTEST" || die "No interactive rebase running"
 389
 390                 output git reset --hard && do_rest
 391                 ;;
 392         -s|--strategy)
 393                 case "$#,$1" in
 394                 *,*=*)
 395                         STRATEGY="-s "$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
 396                 1,*)
 397                         usage ;;
 398                 *)
 399                         STRATEGY="-s $2"
 400                         shift ;;
 401                 esac
 402                 ;;
 403         --merge)
 404                 # we use merge anyway
 405                 ;;
 406         -C*)
 407                 die "Interactive rebase uses merge, so $1 does not make sense"
 408                 ;;
 409         -v|--verbose)
 410                 VERBOSE=t
 411                 ;;
 412         -p|--preserve-merges)
 413                 PRESERVE_MERGES=t
 414                 ;;
 415         -i|--interactive)
 416                 # yeah, we know
 417                 ;;
 418         ''|-h)
 419                 usage
 420                 ;;
 421         *)
 422                 test -d "$DOTEST" &&
 423                         die "Interactive rebase already started"
 424
 425                 git var GIT_COMMITTER_IDENT >/dev/null ||
 426                         die "You need to set your committer info first"
 427
 428                 comment_for_reflog start
 429
 430                 ONTO=
 431                 case "$1" in
 432                 --onto)
 433                         ONTO=$(git rev-parse --verify "$2") ||
 434                                 die "Does not point to a valid commit: $2"
 435                         shift; shift
 436                         ;;
 437                 esac
 438
 439                 require_clean_work_tree
 440
 441                 if test ! -z "$2"
 442                 then
 443                         output git show-ref --verify --quiet "refs/heads/$2" ||
 444                                 die "Invalid branchname: $2"
 445                         output git checkout "$2" ||
 446                                 die "Could not checkout $2"
 447                 fi
 448
 449                 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
 450                 UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
 451
 452                 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
 453
 454                 test -z "$ONTO" && ONTO=$UPSTREAM
 455
 456                 : > "$DOTEST"/interactive || die "Could not mark as interactive"
 457                 git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
 458                         echo "detached HEAD" > "$DOTEST"/head-name
 459
 460                 echo $HEAD > "$DOTEST"/head
 461                 echo $UPSTREAM > "$DOTEST"/upstream
 462                 echo $ONTO > "$DOTEST"/onto
 463                 test -z "$STRATEGY" || echo "$STRATEGY" > "$DOTEST"/strategy
 464                 test t = "$VERBOSE" && : > "$DOTEST"/verbose
 465                 if test t = "$PRESERVE_MERGES"
 466                 then
 467                         # $REWRITTEN contains files for each commit that is
 468                         # reachable by at least one merge base of $HEAD and
 469                         # $UPSTREAM. They are not necessarily rewritten, but
 470                         # their children might be.
 471                         # This ensures that commits on merged, but otherwise
 472                         # unrelated side branches are left alone. (Think "X"
 473                         # in the man page's example.)
 474                         mkdir "$REWRITTEN" &&
 475                         for c in $(git merge-base --all $HEAD $UPSTREAM)
 476                         do
 477                                 echo $ONTO > "$REWRITTEN"/$c ||
 478                                         die "Could not init rewritten commits"
 479                         done
 480                         MERGES_OPTION=
 481                 else
 482                         MERGES_OPTION=--no-merges
 483                 fi
 484
 485                 SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
 486                 SHORTHEAD=$(git rev-parse --short $HEAD)
 487                 SHORTONTO=$(git rev-parse --short $ONTO)
 488                 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
 489                         --abbrev=7 --reverse --left-right --cherry-pick \
 490                         $UPSTREAM...$HEAD | \
 491                         sed -n "s/^>/pick /p" > "$TODO"
 492                 cat >> "$TODO" << EOF
 493
 494 # Rebase $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
 495 #
 496 # Commands:
 497 #  pick = use commit
 498 #  edit = use commit, but stop for amending
 499 #  squash = use commit, but meld into previous commit
 500 #
 501 # If you remove a line here THAT COMMIT WILL BE LOST.
 502 # However, if you remove everything, the rebase will be aborted.
 503 #
 504 EOF
 505
 506                 has_action "$TODO" ||
 507                         die_abort "Nothing to do"
 508
 509                 cp "$TODO" "$TODO".backup
 510                 git_editor "$TODO" ||
 511                         die "Could not execute editor"
 512
 513                 has_action "$TODO" ||
 514                         die_abort "Nothing to do"
 515
 516                 output git checkout $ONTO && do_rest
 517                 ;;
 518         esac
 519         shift
 520 done