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 .git/rebase-apply working files, use the
  18 command 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.
  22
  23 Example:       git-rebase master~1 topic
  24
  25         A---B---C topic                   A'\''--B'\''--C'\'' topic
  26        /                   -->           /
  27   D---E---F---G master          D---E---F---G master
  28 '
  29
  30 SUBDIRECTORY_OK=Yes
  31 OPTIONS_SPEC=
  32 . git-sh-setup
  33 set_reflog_action rebase
  34 require_work_tree
  35 cd_to_toplevel
  36
  37 RESOLVEMSG="
  38 When you have resolved this problem run \"git rebase --continue\".
  39 If you would prefer to skip this patch, instead run \"git rebase --skip\".
  40 To restore the original branch and stop rebasing run \"git rebase --abort\".
  41 "
  42 unset newbase
  43 strategy=recursive
  44 do_merge=
  45 dotest="$GIT_DIR"/rebase-merge
  46 prec=4
  47 verbose=
  48 git_am_opt=
  49
  50 continue_merge () {
  51         test -n "$prev_head" || die "prev_head must be defined"
  52         test -d "$dotest" || die "$dotest directory does not exist"
  53
  54         unmerged=$(git ls-files -u)
  55         if test -n "$unmerged"
  56         then
  57                 echo "You still have unmerged paths in your index"
  58                 echo "did you forget to use git add?"
  59                 die "$RESOLVEMSG"
  60         fi
  61
  62         cmt=`cat "$dotest/current"`
  63         if ! git diff-index --quiet --ignore-submodules HEAD --
  64         then
  65                 if ! git commit --no-verify -C "$cmt"
  66                 then
  67                         echo "Commit failed, please do not call \"git commit\""
  68                         echo "directly, but instead do one of the following: "
  69                         die "$RESOLVEMSG"
  70                 fi
  71                 printf "Committed: %0${prec}d " $msgnum
  72         else
  73                 printf "Already applied: %0${prec}d " $msgnum
  74         fi
  75         git rev-list --pretty=oneline -1 "$cmt" | sed -e 's/^[^ ]* //'
  76
  77         prev_head=`git rev-parse HEAD^0`
  78         # save the resulting commit so we can read-tree on it later
  79         echo "$prev_head" > "$dotest/prev_head"
  80
  81         # onto the next patch:
  82         msgnum=$(($msgnum + 1))
  83         echo "$msgnum" >"$dotest/msgnum"
  84 }
  85
  86 call_merge () {
  87         cmt="$(cat "$dotest/cmt.$1")"
  88         echo "$cmt" > "$dotest/current"
  89         hd=$(git rev-parse --verify HEAD)
  90         cmt_name=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
  91         msgnum=$(cat "$dotest/msgnum")
  92         end=$(cat "$dotest/end")
  93         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
  94         eval GITHEAD_$hd='$(cat "$dotest/onto_name")'
  95         export GITHEAD_$cmt GITHEAD_$hd
  96         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
  97         rv=$?
  98         case "$rv" in
  99         0)
 100                 unset GITHEAD_$cmt GITHEAD_$hd
 101                 return
 102                 ;;
 103         1)
 104                 git rerere
 105                 die "$RESOLVEMSG"
 106                 ;;
 107         2)
 108                 echo "Strategy: $rv $strategy failed, try another" 1>&2
 109                 die "$RESOLVEMSG"
 110                 ;;
 111         *)
 112                 die "Unknown exit code ($rv) from command:" \
 113                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
 114                 ;;
 115         esac
 116 }
 117
 118 move_to_original_branch () {
 119         test -z "$head_name" &&
 120                 head_name="$(cat "$dotest"/head-name)" &&
 121                 onto="$(cat "$dotest"/onto)" &&
 122                 orig_head="$(cat "$dotest"/orig-head)"
 123         case "$head_name" in
 124         refs/*)
 125                 message="rebase finished: $head_name onto $onto"
 126                 git update-ref -m "$message" \
 127                         $head_name $(git rev-parse HEAD) $orig_head &&
 128                 git symbolic-ref HEAD $head_name ||
 129                 die "Could not move back to $head_name"
 130                 ;;
 131         esac
 132 }
 133
 134 finish_rb_merge () {
 135         move_to_original_branch
 136         rm -r "$dotest"
 137         echo "All done."
 138 }
 139
 140 is_interactive () {
 141         test -f "$dotest"/interactive ||
 142         while :; do case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
 143                 shift
 144         done && test -n "$1"
 145 }
 146
 147 test -f "$GIT_DIR"/rebase-apply/applying &&
 148         die 'It looks like git-am is in progress. Cannot rebase.'
 149
 150 is_interactive "$@" && exec git-rebase--interactive "$@"
 151
 152 if test $# -eq 0
 153 then
 154         test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply || usage
 155         test -d "$dotest" -o -f "$GIT_DIR"/rebase-apply/rebasing &&
 156                 die 'A rebase is in progress, try --continue, --skip or --abort.'
 157         die "No arguments given and $GIT_DIR/rebase-apply already exists."
 158 fi
 159
 160 while test $# != 0
 161 do
 162         case "$1" in
 163         --continue)
 164                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
 165                         die "No rebase in progress?"
 166
 167                 git diff-files --quiet --ignore-submodules || {
 168                         echo "You must edit all merge conflicts and then"
 169                         echo "mark them as resolved using git add"
 170                         exit 1
 171                 }
 172                 if test -d "$dotest"
 173                 then
 174                         prev_head=$(cat "$dotest/prev_head")
 175                         end=$(cat "$dotest/end")
 176                         msgnum=$(cat "$dotest/msgnum")
 177                         onto=$(cat "$dotest/onto")
 178                         continue_merge
 179                         while test "$msgnum" -le "$end"
 180                         do
 181                                 call_merge "$msgnum"
 182                                 continue_merge
 183                         done
 184                         finish_rb_merge
 185                         exit
 186                 fi
 187                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
 188                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
 189                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
 190                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
 191                 move_to_original_branch
 192                 exit
 193                 ;;
 194         --skip)
 195                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
 196                         die "No rebase in progress?"
 197
 198                 git reset --hard HEAD || exit $?
 199                 if test -d "$dotest"
 200                 then
 201                         git rerere clear
 202                         prev_head=$(cat "$dotest/prev_head")
 203                         end=$(cat "$dotest/end")
 204                         msgnum=$(cat "$dotest/msgnum")
 205                         msgnum=$(($msgnum + 1))
 206                         onto=$(cat "$dotest/onto")
 207                         while test "$msgnum" -le "$end"
 208                         do
 209                                 call_merge "$msgnum"
 210                                 continue_merge
 211                         done
 212                         finish_rb_merge
 213                         exit
 214                 fi
 215                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
 216                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
 217                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
 218                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
 219                 move_to_original_branch
 220                 exit
 221                 ;;
 222         --abort)
 223                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
 224                         die "No rebase in progress?"
 225
 226                 git rerere clear
 227                 if test -d "$dotest"
 228                 then
 229                         move_to_original_branch
 230                 else
 231                         dotest="$GIT_DIR"/rebase-apply
 232                         move_to_original_branch
 233                 fi
 234                 git reset --hard $(cat "$dotest/orig-head")
 235                 rm -r "$dotest"
 236                 exit
 237                 ;;
 238         --onto)
 239                 test 2 -le "$#" || usage
 240                 newbase="$2"
 241                 shift
 242                 ;;
 243         -M|-m|--m|--me|--mer|--merg|--merge)
 244                 do_merge=t
 245                 ;;
 246         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 247                 --strateg=*|--strategy=*|\
 248         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 249                 case "$#,$1" in
 250                 *,*=*)
 251                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 252                 1,*)
 253                         usage ;;
 254                 *)
 255                         strategy="$2"
 256                         shift ;;
 257                 esac
 258                 do_merge=t
 259                 ;;
 260         -v|--verbose)
 261                 verbose=t
 262                 ;;
 263         --whitespace=*)
 264                 git_am_opt="$git_am_opt $1"
 265                 ;;
 266         -C*)
 267                 git_am_opt="$git_am_opt $1"
 268                 ;;
 269         -*)
 270                 usage
 271                 ;;
 272         *)
 273                 break
 274                 ;;
 275         esac
 276         shift
 277 done
 278
 279 # Make sure we do not have $GIT_DIR/rebase-apply
 280 if test -z "$do_merge"
 281 then
 282         if mkdir "$GIT_DIR"/rebase-apply 2>/dev/null
 283         then
 284                 rmdir "$GIT_DIR"/rebase-apply
 285         else
 286                 echo >&2 '
 287 It seems that I cannot create a rebase-apply directory, and
 288 I wonder if you are in the middle of patch application or another
 289 rebase.  If that is not the case, please
 290         rm -fr '"$GIT_DIR"'/rebase-apply
 291 and run me again.  I am stopping in case you still have something
 292 valuable there.'
 293                 exit 1
 294         fi
 295 else
 296         if test -d "$dotest"
 297         then
 298                 die "previous rebase directory $dotest still exists." \
 299                         'Try git rebase (--continue | --abort | --skip)'
 300         fi
 301 fi
 302
 303 # The tree must be really really clean.
 304 git update-index --ignore-submodules --refresh || exit
 305 diff=$(git diff-index --cached --name-status -r --ignore-submodules HEAD --)
 306 case "$diff" in
 307 ?*)     echo "cannot rebase: your index is not up-to-date"
 308         echo "$diff"
 309         exit 1
 310         ;;
 311 esac
 312
 313 # The upstream head must be given.  Make sure it is valid.
 314 upstream_name="$1"
 315 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 316     die "invalid upstream $upstream_name"
 317
 318 # Make sure the branch to rebase onto is valid.
 319 onto_name=${newbase-"$upstream_name"}
 320 onto=$(git rev-parse --verify "${onto_name}^0") || exit
 321
 322 # If a hook exists, give it a chance to interrupt
 323 if test -x "$GIT_DIR/hooks/pre-rebase"
 324 then
 325         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 326                 echo >&2 "The pre-rebase hook refused to rebase."
 327                 exit 1
 328         }
 329 fi
 330
 331 # If the branch to rebase is given, that is the branch we will rebase
 332 # $branch_name -- branch being rebased, or HEAD (already detached)
 333 # $orig_head -- commit object name of tip of the branch before rebasing
 334 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
 335 switch_to=
 336 case "$#" in
 337 2)
 338         # Is it "rebase other $branchname" or "rebase other $commit"?
 339         branch_name="$2"
 340         switch_to="$2"
 341
 342         if git show-ref --verify --quiet -- "refs/heads/$2" &&
 343            branch=$(git rev-parse --verify "refs/heads/$2" 2>/dev/null)
 344         then
 345                 head_name="refs/heads/$2"
 346         elif branch=$(git rev-parse --verify "$2" 2>/dev/null)
 347         then
 348                 head_name="detached HEAD"
 349         else
 350                 usage
 351         fi
 352         ;;
 353 *)
 354         # Do not need to switch branches, we are already on it.
 355         if branch_name=`git symbolic-ref -q HEAD`
 356         then
 357                 head_name=$branch_name
 358                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 359         else
 360                 head_name="detached HEAD"
 361                 branch_name=HEAD ;# detached
 362         fi
 363         branch=$(git rev-parse --verify "${branch_name}^0") || exit
 364         ;;
 365 esac
 366 orig_head=$branch
 367
 368 # Now we are rebasing commits $upstream..$branch on top of $onto
 369
 370 # Check if we are already based on $onto with linear history,
 371 # but this should be done only when upstream and onto are the same.
 372 mb=$(git merge-base "$onto" "$branch")
 373 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
 374         # linear history?
 375         ! (git rev-list --parents "$onto".."$branch" | grep " .* ") > /dev/null
 376 then
 377         # Lazily switch to the target branch if needed...
 378         test -z "$switch_to" || git checkout "$switch_to"
 379         echo >&2 "Current branch $branch_name is up to date."
 380         exit 0
 381 fi
 382
 383 if test -n "$verbose"
 384 then
 385         echo "Changes from $mb to $onto:"
 386         # We want color (if set), but no pager
 387         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 388 fi
 389
 390 # Detach HEAD and reset the tree
 391 echo "First, rewinding head to replay your work on top of it..."
 392 git checkout -q "$onto^0" || die "could not detach HEAD"
 393 git update-ref ORIG_HEAD $branch
 394
 395 # If the $onto is a proper descendant of the tip of the branch, then
 396 # we just fast forwarded.
 397 if test "$mb" = "$branch"
 398 then
 399         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 400         move_to_original_branch
 401         exit 0
 402 fi
 403
 404 if test -z "$do_merge"
 405 then
 406         git format-patch -k --stdout --full-index --ignore-if-in-upstream \
 407                 "$upstream..$orig_head" |
 408         git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
 409         move_to_original_branch
 410         ret=$?
 411         test 0 != $ret -a -d "$GIT_DIR"/rebase-apply &&
 412                 echo $head_name > "$GIT_DIR"/rebase-apply/head-name &&
 413                 echo $onto > "$GIT_DIR"/rebase-apply/onto &&
 414                 echo $orig_head > "$GIT_DIR"/rebase-apply/orig-head
 415         exit $ret
 416 fi
 417
 418 # start doing a rebase with git-merge
 419 # this is rename-aware if the recursive (default) strategy is used
 420
 421 mkdir -p "$dotest"
 422 echo "$onto" > "$dotest/onto"
 423 echo "$onto_name" > "$dotest/onto_name"
 424 prev_head=$orig_head
 425 echo "$prev_head" > "$dotest/prev_head"
 426 echo "$orig_head" > "$dotest/orig-head"
 427 echo "$head_name" > "$dotest/head-name"
 428
 429 msgnum=0
 430 for cmt in `git rev-list --reverse --no-merges "$upstream..$orig_head"`
 431 do
 432         msgnum=$(($msgnum + 1))
 433         echo "$cmt" > "$dotest/cmt.$msgnum"
 434 done
 435
 436 echo 1 >"$dotest/msgnum"
 437 echo $msgnum >"$dotest/end"
 438
 439 end=$msgnum
 440 msgnum=1
 441
 442 while test "$msgnum" -le "$end"
 443 do
 444         call_merge "$msgnum"
 445         continue_merge
 446 done
 447
 448 finish_rb_merge