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="$DOTEST"/done
  22 REWRITTEN="$DOTEST"/rewritten
  23 PRESERVE_MERGES=
  24 STRATEGY=
  25 VERBOSE=
  26
  27 warn () {
  28         echo "$*" >&2
  29 }
  30
  31 require_clean_work_tree () {
  32         # test if working tree is dirty
  33         git rev-parse --verify HEAD > /dev/null &&
  34         git update-index --refresh &&
  35         git diff-files --quiet &&
  36         git diff-index --cached --quiet HEAD ||
  37         die "Working tree is dirty"
  38 }
  39
  40 ORIG_REFLOG_ACTION="$GIT_REFLOG_ACTION"
  41
  42 comment_for_reflog () {
  43         case "$ORIG_REFLOG_ACTION" in
  44         ''|rebase*)
  45                 GIT_REFLOG_ACTION="rebase -i ($1)"
  46                 export GIT_REFLOG_ACTION
  47         esac
  48 }
  49
  50 mark_action_done () {
  51         sed -e 1q < "$TODO" >> "$DONE"
  52         sed -e 1d < "$TODO" >> "$TODO".new
  53         mv -f "$TODO".new "$TODO"
  54 }
  55
  56 make_patch () {
  57         parent_sha1=$(git rev-parse --verify "$1"^ 2> /dev/null)
  58         git diff "$parent_sha1".."$1" > "$DOTEST"/patch
  59 }
  60
  61 die_with_patch () {
  62         make_patch "$1"
  63         die "$2"
  64 }
  65
  66 die_abort () {
  67         rm -rf "$DOTEST"
  68         die "$1"
  69 }
  70
  71 pick_one () {
  72         case "$1" in -n) sha1=$2 ;; *) sha1=$1 ;; esac
  73         git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
  74         test -d "$REWRITTEN" &&
  75                 pick_one_preserving_merges "$@" && return
  76         parent_sha1=$(git rev-parse --verify $sha1^ 2>/dev/null)
  77         current_sha1=$(git rev-parse --verify HEAD)
  78         if [ $current_sha1 = $parent_sha1 ]; then
  79                 git reset --hard $sha1
  80                 sha1=$(git rev-parse --short $sha1)
  81                 warn Fast forward to $sha1
  82         else
  83                 git cherry-pick $STRATEGY "$@"
  84         fi
  85 }
  86
  87 pick_one_preserving_merges () {
  88         case "$1" in -n) sha1=$2 ;; *) sha1=$1 ;; esac
  89         sha1=$(git rev-parse $sha1)
  90
  91         if [ -f "$DOTEST"/current-commit ]
  92         then
  93                 current_commit=$(cat "$DOTEST"/current-commit) &&
  94                 git rev-parse HEAD > "$REWRITTEN"/$current_commit &&
  95                 rm "$DOTEST"/current-commit ||
  96                 die "Cannot write current commit's replacement sha1"
  97         fi
  98
  99         # rewrite parents; if none were rewritten, we can fast-forward.
 100         fast_forward=t
 101         preserve=t
 102         new_parents=
 103         for p in $(git rev-list --parents -1 $sha1 | cut -d\  -f2-)
 104         do
 105                 if [ -f "$REWRITTEN"/$p ]
 106                 then
 107                         preserve=f
 108                         new_p=$(cat "$REWRITTEN"/$p)
 109                         test $p != $new_p && fast_forward=f
 110                         case "$new_parents" in
 111                         *$new_p*)
 112                                 ;; # do nothing; that parent is already there
 113                         *)
 114                                 new_parents="$new_parents $new_p"
 115                         esac
 116                 fi
 117         done
 118         case $fast_forward in
 119         t)
 120                 echo "Fast forward to $sha1"
 121                 test $preserve=f && echo $sha1 > "$REWRITTEN"/$sha1
 122                 ;;
 123         f)
 124                 test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
 125
 126                 first_parent=$(expr "$new_parents" : " \([^ ]*\)")
 127                 # detach HEAD to current parent
 128                 git checkout $first_parent 2> /dev/null ||
 129                         die "Cannot move HEAD to $first_parent"
 130
 131                 echo $sha1 > "$DOTEST"/current-commit
 132                 case "$new_parents" in
 133                 \ *\ *)
 134                         # redo merge
 135                         author_script=$(get_author_ident_from_commit $sha1)
 136                         eval "$author_script"
 137                         msg="$(git cat-file commit $sha1 | \
 138                                 sed -e '1,/^$/d' -e "s/[\"\\]/\\\\&/g")"
 139                         # NEEDSWORK: give rerere a chance
 140                         if ! git merge $STRATEGY -m "$msg" $new_parents
 141                         then
 142                                 echo "$msg" > "$GIT_DIR"/MERGE_MSG
 143                                 warn Error redoing merge $sha1
 144                                 warn
 145                                 warn After fixup, please use
 146                                 die "$author_script git commit"
 147                         fi
 148                         ;;
 149                 *)
 150                         git cherry-pick $STRATEGY "$@" ||
 151                                 die_with_patch $sha1 "Could not pick $sha1"
 152                 esac
 153         esac
 154 }
 155
 156 do_next () {
 157         read command sha1 rest < "$TODO"
 158         case "$command" in
 159         \#|'')
 160                 mark_action_done
 161                 continue
 162                 ;;
 163         pick)
 164                 comment_for_reflog pick
 165
 166                 mark_action_done
 167                 pick_one $sha1 ||
 168                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 169                 ;;
 170         edit)
 171                 comment_for_reflog edit
 172
 173                 mark_action_done
 174                 pick_one $sha1 ||
 175                         die_with_patch $sha1 "Could not apply $sha1... $rest"
 176                 make_patch $sha1
 177                 warn
 178                 warn "You can amend the commit now, with"
 179                 warn
 180                 warn "  git commit --amend"
 181                 warn
 182                 exit 0
 183                 ;;
 184         squash)
 185                 comment_for_reflog squash
 186
 187                 test -z "$(grep -ve '^$' -e '^#' < $DONE)" &&
 188                         die "Cannot 'squash' without a previous commit"
 189
 190                 mark_action_done
 191                 failed=f
 192                 pick_one -n $sha1 || failed=t
 193                 MSG="$DOTEST"/message
 194                 echo "# This is a combination of two commits." > "$MSG"
 195                 echo "# The first commit's message is:" >> "$MSG"
 196                 echo >> "$MSG"
 197                 git cat-file commit HEAD | sed -e '1,/^$/d' >> "$MSG"
 198                 echo >> "$MSG"
 199                 echo "# And this is the 2nd commit message:" >> "$MSG"
 200                 echo >> "$MSG"
 201                 git cat-file commit $sha1 | sed -e '1,/^$/d' >> "$MSG"
 202                 git reset --soft HEAD^
 203                 author_script=$(get_author_ident_from_commit $sha1)
 204                 case $failed in
 205                 f)
 206                         # This is like --amend, but with a different message
 207                         eval "$author_script"
 208                         export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
 209                         git commit -F "$MSG" -e
 210                         ;;
 211                 t)
 212                         cp "$MSG" "$GIT_DIR"/MERGE_MSG
 213                         warn
 214                         warn "Could not apply $sha1... $rest"
 215                         warn "After you fixed that, commit the result with"
 216                         warn
 217                         warn "  $(echo $author_script | tr '\012' ' ') \\"
 218                         warn "    git commit -F \"$GIT_DIR\"/MERGE_MSG -e"
 219                         die_with_patch $sha1 ""
 220                 esac
 221                 ;;
 222         *)
 223                 warn "Unknown command: $command $sha1 $rest"
 224                 die_with_patch $sha1 "Please fix this in the file $TODO."
 225         esac
 226         test -s "$TODO" && return
 227
 228         comment_for_reflog finish &&
 229         HEADNAME=$(cat "$DOTEST"/head-name) &&
 230         OLDHEAD=$(cat "$DOTEST"/head) &&
 231         SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
 232         if [ -d "$REWRITTEN" ]
 233         then
 234                 test -f "$DOTEST"/current-commit &&
 235                         current_commit=$(cat "$DOTEST"/current-commit) &&
 236                         git rev-parse HEAD > "$REWRITTEN"/$current_commit
 237                 NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
 238         else
 239                 NEWHEAD=$(git rev-parse HEAD)
 240         fi &&
 241         message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
 242         git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
 243         git symbolic-ref HEAD $HEADNAME &&
 244         rm -rf "$DOTEST" &&
 245         warn "Successfully rebased and updated $HEADNAME."
 246
 247         exit
 248 }
 249
 250 do_rest () {
 251         while :
 252         do
 253                 do_next
 254         done
 255         test -f "$DOTEST"/verbose &&
 256                 git diff --stat $(cat "$DOTEST"/head)..HEAD
 257         exit
 258 }
 259
 260 while case $# in 0) break ;; esac
 261 do
 262         case "$1" in
 263         --continue)
 264                 comment_for_reflog continue
 265
 266                 test -d "$DOTEST" || die "No interactive rebase running"
 267
 268                 require_clean_work_tree
 269                 do_rest
 270                 ;;
 271         --abort)
 272                 comment_for_reflog abort
 273
 274                 test -d "$DOTEST" || die "No interactive rebase running"
 275
 276                 HEADNAME=$(cat "$DOTEST"/head-name)
 277                 HEAD=$(cat "$DOTEST"/head)
 278                 git symbolic-ref HEAD $HEADNAME &&
 279                 git reset --hard $HEAD &&
 280                 rm -rf "$DOTEST"
 281                 exit
 282                 ;;
 283         --skip)
 284                 comment_for_reflog skip
 285
 286                 test -d "$DOTEST" || die "No interactive rebase running"
 287
 288                 git reset --hard && do_rest
 289                 ;;
 290         -s|--strategy)
 291                 shift
 292                 case "$#,$1" in
 293                 *,*=*)
 294                         STRATEGY="-s `expr "z$1" : 'z-[^=]*=\(.*\)'`" ;;
 295                 1,*)
 296                         usage ;;
 297                 *)
 298                         STRATEGY="-s $2"
 299                         shift ;;
 300                 esac
 301                 ;;
 302         --merge)
 303                 # we use merge anyway
 304                 ;;
 305         -C*)
 306                 die "Interactive rebase uses merge, so $1 does not make sense"
 307                 ;;
 308         -v|--verbose)
 309                 VERBOSE=t
 310                 ;;
 311         -p|--preserve-merges)
 312                 PRESERVE_MERGES=t
 313                 ;;
 314         -i|--interactive)
 315                 # yeah, we know
 316                 ;;
 317         ''|-h)
 318                 usage
 319                 ;;
 320         *)
 321                 test -d "$DOTEST" &&
 322                         die "Interactive rebase already started"
 323
 324                 git var GIT_COMMITTER_IDENT >/dev/null ||
 325                         die "You need to set your committer info first"
 326
 327                 comment_for_reflog start
 328
 329                 ONTO=
 330                 case "$1" in
 331                 --onto)
 332                         ONTO=$(git rev-parse --verify "$2") ||
 333                                 die "Does not point to a valid commit: $2"
 334                         shift; shift
 335                         ;;
 336                 esac
 337
 338                 require_clean_work_tree
 339
 340                 if [ ! -z "$2"]
 341                 then
 342                         git show-ref --verify --quiet "refs/heads/$2" ||
 343                                 die "Invalid branchname: $2"
 344                         git checkout "$2" ||
 345                                 die "Could not checkout $2"
 346                 fi
 347
 348                 HEAD=$(git rev-parse --verify HEAD) || die "No HEAD?"
 349                 UPSTREAM=$(git rev-parse --verify "$1") || die "Invalid base"
 350
 351                 test -z "$ONTO" && ONTO=$UPSTREAM
 352
 353                 mkdir "$DOTEST" || die "Could not create temporary $DOTEST"
 354                 : > "$DOTEST"/interactive || die "Could not mark as interactive"
 355                 git symbolic-ref HEAD > "$DOTEST"/head-name ||
 356                         die "Could not get HEAD"
 357
 358                 echo $HEAD > "$DOTEST"/head
 359                 echo $UPSTREAM > "$DOTEST"/upstream
 360                 echo $ONTO > "$DOTEST"/onto
 361                 test t = "$VERBOSE" && : > "$DOTEST"/verbose
 362                 if [ t = "$PRESERVE_MERGES" ]
 363                 then
 364                         # $REWRITTEN contains files for each commit that is
 365                         # reachable by at least one merge base of $HEAD and
 366                         # $UPSTREAM. They are not necessarily rewritten, but
 367                         # their children might be.
 368                         # This ensures that commits on merged, but otherwise
 369                         # unrelated side branches are left alone. (Think "X"
 370                         # in the man page's example.)
 371                         mkdir "$REWRITTEN" &&
 372                         for c in $(git merge-base --all $HEAD $UPSTREAM)
 373                         do
 374                                 echo $ONTO > "$REWRITTEN"/$c ||
 375                                         die "Could not init rewritten commits"
 376                         done
 377                         MERGES_OPTION=
 378                 else
 379                         MERGES_OPTION=--no-merges
 380                 fi
 381
 382                 SHORTUPSTREAM=$(git rev-parse --short $UPSTREAM)
 383                 SHORTHEAD=$(git rev-parse --short $HEAD)
 384                 SHORTONTO=$(git rev-parse --short $ONTO)
 385                 cat > "$TODO" << EOF
 386 # Rebasing $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
 387 #
 388 # Commands:
 389 #  pick = use commit
 390 #  edit = use commit, but stop for amending
 391 #  squash = use commit, but meld into previous commit
 392 EOF
 393                 git rev-list $MERGES_OPTION --pretty=oneline --abbrev-commit \
 394                         --abbrev=7 --reverse $UPSTREAM..$HEAD | \
 395                         sed "s/^/pick /" >> "$TODO"
 396
 397                 test -z "$(grep -ve '^$' -e '^#' < $TODO)" &&
 398                         die_abort "Nothing to do"
 399
 400                 cp "$TODO" "$TODO".backup
 401                 ${VISUAL:-${EDITOR:-vi}} "$TODO" ||
 402                         die "Could not execute editor"
 403
 404                 test -z "$(grep -ve '^$' -e '^#' < $TODO)" &&
 405                         die_abort "Nothing to do"
 406
 407                 git checkout $ONTO && do_rest
 408         esac
 409         shift
 410 done