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