git-rebase.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano.
   4 #
   5
   6 USAGE='[--interactive | -i] [-v] [--onto <newbase>] <upstream> [<branch>]'
   7 LONG_USAGE='git-rebase replaces <branch> with a new branch of the
   8 same name.  When the --onto option is provided the new branch starts
   9 out with a HEAD equal to <newbase>, otherwise it is equal to <upstream>
  10 It then attempts to create a new commit for each commit from the original
  11 <branch> that does not exist in the <upstream> branch.
  12
  13 It is possible that a merge failure will prevent this process from being
  14 completely automatic.  You will have to resolve any such merge failure
  15 and run git rebase --continue.  Another option is to bypass the commit
  16 that caused the merge failure with git rebase --skip.  To restore the
  17 original <branch> and remove the .dotest working files, use the command
  18 git rebase --abort instead.
  19
  20 Note that if <branch> is not specified on the command line, the
  21 currently checked out branch is used.  You must be in the top
  22 directory of your project to start (or continue) a rebase.
  23
  24 Example:       git-rebase master~1 topic
  25
  26         A---B---C topic                   A'\''--B'\''--C'\'' topic
  27        /                   -->           /
  28   D---E---F---G master          D---E---F---G master
  29 '
  30
  31 SUBDIRECTORY_OK=Yes
  32 OPTIONS_SPEC=
  33 . git-sh-setup
  34 set_reflog_action rebase
  35 require_work_tree
  36 cd_to_toplevel
  37
  38 RESOLVEMSG="
  39 When you have resolved this problem run \"git rebase --continue\".
  40 If you would prefer to skip this patch, instead run \"git rebase --skip\".
  41 To restore the original branch and stop rebasing run \"git rebase --abort\".
  42 "
  43 unset newbase
  44 strategy=recursive
  45 do_merge=
  46 dotest=$GIT_DIR/.dotest-merge
  47 prec=4
  48 verbose=
  49 git_am_opt=
  50
  51 continue_merge () {
  52         test -n "$prev_head" || die "prev_head must be defined"
  53         test -d "$dotest" || die "$dotest directory does not exist"
  54
  55         unmerged=$(git ls-files -u)
  56         if test -n "$unmerged"
  57         then
  58                 echo "You still have unmerged paths in your index"
  59                 echo "did you forget to use git add?"
  60                 die "$RESOLVEMSG"
  61         fi
  62
  63         cmt=`cat "$dotest/current"`
  64         if ! git diff-index --quiet HEAD
  65         then
  66                 if ! git-commit -C "$cmt"
  67                 then
  68                         echo "Commit failed, please do not call \"git commit\""
  69                         echo "directly, but instead do one of the following: "
  70                         die "$RESOLVEMSG"
  71                 fi
  72                 printf "Committed: %0${prec}d " $msgnum
  73         else
  74                 printf "Already applied: %0${prec}d " $msgnum
  75         fi
  76         git rev-list --pretty=oneline -1 "$cmt" | sed -e 's/^[^ ]* //'
  77
  78         prev_head=`git rev-parse HEAD^0`
  79         # save the resulting commit so we can read-tree on it later
  80         echo "$prev_head" > "$dotest/prev_head"
  81
  82         # onto the next patch:
  83         msgnum=$(($msgnum + 1))
  84         echo "$msgnum" >"$dotest/msgnum"
  85 }
  86
  87 call_merge () {
  88         cmt="$(cat "$dotest/cmt.$1")"
  89         echo "$cmt" > "$dotest/current"
  90         hd=$(git rev-parse --verify HEAD)
  91         cmt_name=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
  92         msgnum=$(cat "$dotest/msgnum")
  93         end=$(cat "$dotest/end")
  94         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
  95         eval GITHEAD_$hd='$(cat "$dotest/onto_name")'
  96         export GITHEAD_$cmt GITHEAD_$hd
  97         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
  98         rv=$?
  99         case "$rv" in
 100         0)
 101                 unset GITHEAD_$cmt GITHEAD_$hd
 102                 return
 103                 ;;
 104         1)
 105                 git rerere
 106                 die "$RESOLVEMSG"
 107                 ;;
 108         2)
 109                 echo "Strategy: $rv $strategy failed, try another" 1>&2
 110                 die "$RESOLVEMSG"
 111                 ;;
 112         *)
 113                 die "Unknown exit code ($rv) from command:" \
 114                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
 115                 ;;
 116         esac
 117 }
 118
 119 move_to_original_branch () {
 120         test -z "$head_name" &&
 121                 head_name="$(cat "$dotest"/head-name)" &&
 122                 onto="$(cat "$dotest"/onto)" &&
 123                 orig_head="$(cat "$dotest"/orig-head)"
 124         case "$head_name" in
 125         refs/*)
 126                 message="rebase finished: $head_name onto $onto"
 127                 git update-ref -m "$message" \
 128                         $head_name $(git rev-parse HEAD) $orig_head &&
 129                 git symbolic-ref HEAD $head_name ||
 130                 die "Could not move back to $head_name"
 131                 ;;
 132         esac
 133 }
 134
 135 finish_rb_merge () {
 136         move_to_original_branch
 137         rm -r "$dotest"
 138         echo "All done."
 139 }
 140
 141 is_interactive () {
 142         test -f "$dotest"/interactive ||
 143         while :; do case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
 144                 shift
 145         done && test -n "$1"
 146 }
 147
 148 is_interactive "$@" && exec git-rebase--interactive "$@"
 149
 150 while test $# != 0
 151 do
 152         case "$1" in
 153         --continue)
 154                 git diff-files --quiet || {
 155                         echo "You must edit all merge conflicts and then"
 156                         echo "mark them as resolved using git add"
 157                         exit 1
 158                 }
 159                 if test -d "$dotest"
 160                 then
 161                         prev_head=$(cat "$dotest/prev_head")
 162                         end=$(cat "$dotest/end")
 163                         msgnum=$(cat "$dotest/msgnum")
 164                         onto=$(cat "$dotest/onto")
 165                         continue_merge
 166                         while test "$msgnum" -le "$end"
 167                         do
 168                                 call_merge "$msgnum"
 169                                 continue_merge
 170                         done
 171                         finish_rb_merge
 172                         exit
 173                 fi
 174                 head_name=$(cat .dotest/head-name) &&
 175                 onto=$(cat .dotest/onto) &&
 176                 orig_head=$(cat .dotest/orig-head) &&
 177                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
 178                 move_to_original_branch
 179                 exit
 180                 ;;
 181         --skip)
 182                 git reset --hard HEAD || exit $?
 183                 if test -d "$dotest"
 184                 then
 185                         git rerere clear
 186                         prev_head=$(cat "$dotest/prev_head")
 187                         end=$(cat "$dotest/end")
 188                         msgnum=$(cat "$dotest/msgnum")
 189                         msgnum=$(($msgnum + 1))
 190                         onto=$(cat "$dotest/onto")
 191                         while test "$msgnum" -le "$end"
 192                         do
 193                                 call_merge "$msgnum"
 194                                 continue_merge
 195                         done
 196                         finish_rb_merge
 197                         exit
 198                 fi
 199                 head_name=$(cat .dotest/head-name) &&
 200                 onto=$(cat .dotest/onto) &&
 201                 orig_head=$(cat .dotest/orig-head) &&
 202                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
 203                 move_to_original_branch
 204                 exit
 205                 ;;
 206         --abort)
 207                 git rerere clear
 208                 if test -d "$dotest"
 209                 then
 210                         move_to_original_branch
 211                         rm -r "$dotest"
 212                 elif test -d .dotest
 213                 then
 214                         dotest=.dotest
 215                         move_to_original_branch
 216                         rm -r .dotest
 217                 else
 218                         die "No rebase in progress?"
 219                 fi
 220                 git reset --hard ORIG_HEAD
 221                 exit
 222                 ;;
 223         --onto)
 224                 test 2 -le "$#" || usage
 225                 newbase="$2"
 226                 shift
 227                 ;;
 228         -M|-m|--m|--me|--mer|--merg|--merge)
 229                 do_merge=t
 230                 ;;
 231         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 232                 --strateg=*|--strategy=*|\
 233         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 234                 case "$#,$1" in
 235                 *,*=*)
 236                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 237                 1,*)
 238                         usage ;;
 239                 *)
 240                         strategy="$2"
 241                         shift ;;
 242                 esac
 243                 do_merge=t
 244                 ;;
 245         -v|--verbose)
 246                 verbose=t
 247                 ;;
 248         --whitespace=*)
 249                 git_am_opt="$git_am_opt $1"
 250                 ;;
 251         -C*)
 252                 git_am_opt="$git_am_opt $1"
 253                 ;;
 254         -*)
 255                 usage
 256                 ;;
 257         *)
 258                 break
 259                 ;;
 260         esac
 261         shift
 262 done
 263
 264 # Make sure we do not have .dotest
 265 if test -z "$do_merge"
 266 then
 267         if mkdir .dotest
 268         then
 269                 rmdir .dotest
 270         else
 271                 echo >&2 '
 272 It seems that I cannot create a .dotest directory, and I wonder if you
 273 are in the middle of patch application or another rebase.  If that is not
 274 the case, please rm -fr .dotest and run me again.  I am stopping in case
 275 you still have something valuable there.'
 276                 exit 1
 277         fi
 278 else
 279         if test -d "$dotest"
 280         then
 281                 die "previous dotest directory $dotest still exists." \
 282                         'try git-rebase < --continue | --abort >'
 283         fi
 284 fi
 285
 286 # The tree must be really really clean.
 287 git update-index --refresh || exit
 288 diff=$(git diff-index --cached --name-status -r HEAD)
 289 case "$diff" in
 290 ?*)     echo "cannot rebase: your index is not up-to-date"
 291         echo "$diff"
 292         exit 1
 293         ;;
 294 esac
 295
 296 # The upstream head must be given.  Make sure it is valid.
 297 upstream_name="$1"
 298 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 299     die "invalid upstream $upstream_name"
 300
 301 # Make sure the branch to rebase onto is valid.
 302 onto_name=${newbase-"$upstream_name"}
 303 onto=$(git rev-parse --verify "${onto_name}^0") || exit
 304
 305 # If a hook exists, give it a chance to interrupt
 306 if test -x "$GIT_DIR/hooks/pre-rebase"
 307 then
 308         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 309                 echo >&2 "The pre-rebase hook refused to rebase."
 310                 exit 1
 311         }
 312 fi
 313
 314 # If the branch to rebase is given, first switch to it.
 315 case "$#" in
 316 2)
 317         branch_name="$2"
 318         git-checkout "$2" || usage
 319         ;;
 320 *)
 321         if branch_name=`git symbolic-ref -q HEAD`
 322         then
 323                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 324         else
 325                 branch_name=HEAD ;# detached
 326         fi
 327         ;;
 328 esac
 329 branch=$(git rev-parse --verify "${branch_name}^0") || exit
 330
 331 # Now we are rebasing commits $upstream..$branch on top of $onto
 332
 333 # Check if we are already based on $onto with linear history,
 334 # but this should be done only when upstream and onto are the same.
 335 mb=$(git merge-base "$onto" "$branch")
 336 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
 337         # linear history?
 338         ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
 339 then
 340         echo >&2 "Current branch $branch_name is up to date."
 341         exit 0
 342 fi
 343
 344 if test -n "$verbose"
 345 then
 346         echo "Changes from $mb to $onto:"
 347         # We want color (if set), but no pager
 348         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 349 fi
 350
 351 # move to a detached HEAD
 352 orig_head=$(git rev-parse HEAD^0)
 353 head_name=$(git symbolic-ref HEAD 2> /dev/null)
 354 case "$head_name" in
 355 '')
 356         head_name="detached HEAD"
 357         ;;
 358 *)
 359         git checkout "$orig_head" > /dev/null 2>&1 ||
 360                 die "could not detach HEAD"
 361         ;;
 362 esac
 363
 364 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
 365 echo "First, rewinding head to replay your work on top of it..."
 366 git-reset --hard "$onto"
 367
 368 # If the $onto is a proper descendant of the tip of the branch, then
 369 # we just fast forwarded.
 370 if test "$mb" = "$branch"
 371 then
 372         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 373         move_to_original_branch
 374         exit 0
 375 fi
 376
 377 if test -z "$do_merge"
 378 then
 379         git format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
 380         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG" &&
 381         move_to_original_branch
 382         ret=$?
 383         test 0 != $ret -a -d .dotest &&
 384                 echo $head_name > .dotest/head-name &&
 385                 echo $onto > .dotest/onto &&
 386                 echo $orig_head > .dotest/orig-head
 387         exit $ret
 388 fi
 389
 390 # start doing a rebase with git-merge
 391 # this is rename-aware if the recursive (default) strategy is used
 392
 393 mkdir -p "$dotest"
 394 echo "$onto" > "$dotest/onto"
 395 echo "$onto_name" > "$dotest/onto_name"
 396 prev_head=$orig_head
 397 echo "$prev_head" > "$dotest/prev_head"
 398 echo "$orig_head" > "$dotest/orig-head"
 399 echo "$head_name" > "$dotest/head-name"
 400
 401 msgnum=0
 402 for cmt in `git rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
 403 do
 404         msgnum=$(($msgnum + 1))
 405         echo "$cmt" > "$dotest/cmt.$msgnum"
 406 done
 407
 408 echo 1 >"$dotest/msgnum"
 409 echo $msgnum >"$dotest/end"
 410
 411 end=$msgnum
 412 msgnum=1
 413
 414 while test "$msgnum" -le "$end"
 415 do
 416         call_merge "$msgnum"
 417         continue_merge
 418 done
 419
 420 finish_rb_merge