git-rebase.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano.
   4 #
   5
   6 USAGE='[--interactive | -i] [-v] [--force-rebase | -f] [--onto <newbase>] [<upstream>|--root] [<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 OK_TO_SKIP_PRE_REBASE=
  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="$GIT_DIR"/rebase-merge
  47 prec=4
  48 verbose=
  49 git_am_opt=
  50 rebase_root=
  51 force_rebase=
  52
  53 continue_merge () {
  54         test -n "$prev_head" || die "prev_head must be defined"
  55         test -d "$dotest" || die "$dotest directory does not exist"
  56
  57         unmerged=$(git ls-files -u)
  58         if test -n "$unmerged"
  59         then
  60                 echo "You still have unmerged paths in your index"
  61                 echo "did you forget to use git add?"
  62                 die "$RESOLVEMSG"
  63         fi
  64
  65         cmt=`cat "$dotest/current"`
  66         if ! git diff-index --quiet --ignore-submodules HEAD --
  67         then
  68                 if ! git commit --no-verify -C "$cmt"
  69                 then
  70                         echo "Commit failed, please do not call \"git commit\""
  71                         echo "directly, but instead do one of the following: "
  72                         die "$RESOLVEMSG"
  73                 fi
  74                 printf "Committed: %0${prec}d " $msgnum
  75         else
  76                 printf "Already applied: %0${prec}d " $msgnum
  77         fi
  78         git rev-list --pretty=oneline -1 "$cmt" | sed -e 's/^[^ ]* //'
  79
  80         prev_head=`git rev-parse HEAD^0`
  81         # save the resulting commit so we can read-tree on it later
  82         echo "$prev_head" > "$dotest/prev_head"
  83
  84         # onto the next patch:
  85         msgnum=$(($msgnum + 1))
  86         echo "$msgnum" >"$dotest/msgnum"
  87 }
  88
  89 call_merge () {
  90         cmt="$(cat "$dotest/cmt.$1")"
  91         echo "$cmt" > "$dotest/current"
  92         hd=$(git rev-parse --verify HEAD)
  93         cmt_name=$(git symbolic-ref HEAD 2> /dev/null || echo HEAD)
  94         msgnum=$(cat "$dotest/msgnum")
  95         end=$(cat "$dotest/end")
  96         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
  97         eval GITHEAD_$hd='$(cat "$dotest/onto_name")'
  98         export GITHEAD_$cmt GITHEAD_$hd
  99         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
 100         rv=$?
 101         case "$rv" in
 102         0)
 103                 unset GITHEAD_$cmt GITHEAD_$hd
 104                 return
 105                 ;;
 106         1)
 107                 git rerere
 108                 die "$RESOLVEMSG"
 109                 ;;
 110         2)
 111                 echo "Strategy: $rv $strategy failed, try another" 1>&2
 112                 die "$RESOLVEMSG"
 113                 ;;
 114         *)
 115                 die "Unknown exit code ($rv) from command:" \
 116                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
 117                 ;;
 118         esac
 119 }
 120
 121 move_to_original_branch () {
 122         test -z "$head_name" &&
 123                 head_name="$(cat "$dotest"/head-name)" &&
 124                 onto="$(cat "$dotest"/onto)" &&
 125                 orig_head="$(cat "$dotest"/orig-head)"
 126         case "$head_name" in
 127         refs/*)
 128                 message="rebase finished: $head_name onto $onto"
 129                 git update-ref -m "$message" \
 130                         $head_name $(git rev-parse HEAD) $orig_head &&
 131                 git symbolic-ref HEAD $head_name ||
 132                 die "Could not move back to $head_name"
 133                 ;;
 134         esac
 135 }
 136
 137 finish_rb_merge () {
 138         move_to_original_branch
 139         rm -r "$dotest"
 140         echo "All done."
 141 }
 142
 143 is_interactive () {
 144         while test $# != 0
 145         do
 146                 case "$1" in
 147                         -i|--interactive)
 148                                 interactive_rebase=explicit
 149                                 break
 150                         ;;
 151                         -p|--preserve-merges)
 152                                 interactive_rebase=implied
 153                         ;;
 154                 esac
 155                 shift
 156         done
 157
 158         if [ "$interactive_rebase" = implied ]; then
 159                 GIT_EDITOR=:
 160                 export GIT_EDITOR
 161         fi
 162
 163         test -n "$interactive_rebase" || test -f "$dotest"/interactive
 164 }
 165
 166 run_pre_rebase_hook () {
 167         if test -z "$OK_TO_SKIP_PRE_REBASE" &&
 168            test -x "$GIT_DIR/hooks/pre-rebase"
 169         then
 170                 "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 171                         echo >&2 "The pre-rebase hook refused to rebase."
 172                         exit 1
 173                 }
 174         fi
 175 }
 176
 177 test -f "$GIT_DIR"/rebase-apply/applying &&
 178         die 'It looks like git-am is in progress. Cannot rebase.'
 179
 180 is_interactive "$@" && exec git-rebase--interactive "$@"
 181
 182 if test $# -eq 0
 183 then
 184         test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply || usage
 185         test -d "$dotest" -o -f "$GIT_DIR"/rebase-apply/rebasing &&
 186                 die 'A rebase is in progress, try --continue, --skip or --abort.'
 187         die "No arguments given and $GIT_DIR/rebase-apply already exists."
 188 fi
 189
 190 while test $# != 0
 191 do
 192         case "$1" in
 193         --no-verify)
 194                 OK_TO_SKIP_PRE_REBASE=yes
 195                 ;;
 196         --continue)
 197                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
 198                         die "No rebase in progress?"
 199
 200                 git diff-files --quiet --ignore-submodules || {
 201                         echo "You must edit all merge conflicts and then"
 202                         echo "mark them as resolved using git add"
 203                         exit 1
 204                 }
 205                 if test -d "$dotest"
 206                 then
 207                         prev_head=$(cat "$dotest/prev_head")
 208                         end=$(cat "$dotest/end")
 209                         msgnum=$(cat "$dotest/msgnum")
 210                         onto=$(cat "$dotest/onto")
 211                         continue_merge
 212                         while test "$msgnum" -le "$end"
 213                         do
 214                                 call_merge "$msgnum"
 215                                 continue_merge
 216                         done
 217                         finish_rb_merge
 218                         exit
 219                 fi
 220                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
 221                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
 222                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
 223                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
 224                 move_to_original_branch
 225                 exit
 226                 ;;
 227         --skip)
 228                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
 229                         die "No rebase in progress?"
 230
 231                 git reset --hard HEAD || exit $?
 232                 if test -d "$dotest"
 233                 then
 234                         git rerere clear
 235                         prev_head=$(cat "$dotest/prev_head")
 236                         end=$(cat "$dotest/end")
 237                         msgnum=$(cat "$dotest/msgnum")
 238                         msgnum=$(($msgnum + 1))
 239                         onto=$(cat "$dotest/onto")
 240                         while test "$msgnum" -le "$end"
 241                         do
 242                                 call_merge "$msgnum"
 243                                 continue_merge
 244                         done
 245                         finish_rb_merge
 246                         exit
 247                 fi
 248                 head_name=$(cat "$GIT_DIR"/rebase-apply/head-name) &&
 249                 onto=$(cat "$GIT_DIR"/rebase-apply/onto) &&
 250                 orig_head=$(cat "$GIT_DIR"/rebase-apply/orig-head) &&
 251                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
 252                 move_to_original_branch
 253                 exit
 254                 ;;
 255         --abort)
 256                 test -d "$dotest" -o -d "$GIT_DIR"/rebase-apply ||
 257                         die "No rebase in progress?"
 258
 259                 git rerere clear
 260                 if test -d "$dotest"
 261                 then
 262                         move_to_original_branch
 263                 else
 264                         dotest="$GIT_DIR"/rebase-apply
 265                         move_to_original_branch
 266                 fi
 267                 git reset --hard $(cat "$dotest/orig-head")
 268                 rm -r "$dotest"
 269                 exit
 270                 ;;
 271         --onto)
 272                 test 2 -le "$#" || usage
 273                 newbase="$2"
 274                 shift
 275                 ;;
 276         -M|-m|--m|--me|--mer|--merg|--merge)
 277                 do_merge=t
 278                 ;;
 279         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 280                 --strateg=*|--strategy=*|\
 281         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 282                 case "$#,$1" in
 283                 *,*=*)
 284                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 285                 1,*)
 286                         usage ;;
 287                 *)
 288                         strategy="$2"
 289                         shift ;;
 290                 esac
 291                 do_merge=t
 292                 ;;
 293         -v|--verbose)
 294                 verbose=t
 295                 ;;
 296         --whitespace=*)
 297                 git_am_opt="$git_am_opt $1"
 298                 case "$1" in
 299                 --whitespace=fix|--whitespace=strip)
 300                         force_rebase=t
 301                         ;;
 302                 esac
 303                 ;;
 304         -C*)
 305                 git_am_opt="$git_am_opt $1"
 306                 ;;
 307         --root)
 308                 rebase_root=t
 309                 ;;
 310         -f|--f|--fo|--for|--forc|force|--force-r|--force-re|--force-reb|--force-reba|--force_rebas|--force-rebase)
 311                 force_rebase=t
 312                 ;;
 313         -*)
 314                 usage
 315                 ;;
 316         *)
 317                 break
 318                 ;;
 319         esac
 320         shift
 321 done
 322 test $# -gt 2 && usage
 323
 324 # Make sure we do not have $GIT_DIR/rebase-apply
 325 if test -z "$do_merge"
 326 then
 327         if mkdir "$GIT_DIR"/rebase-apply 2>/dev/null
 328         then
 329                 rmdir "$GIT_DIR"/rebase-apply
 330         else
 331                 echo >&2 '
 332 It seems that I cannot create a rebase-apply directory, and
 333 I wonder if you are in the middle of patch application or another
 334 rebase.  If that is not the case, please
 335         rm -fr '"$GIT_DIR"'/rebase-apply
 336 and run me again.  I am stopping in case you still have something
 337 valuable there.'
 338                 exit 1
 339         fi
 340 else
 341         if test -d "$dotest"
 342         then
 343                 die "previous rebase directory $dotest still exists." \
 344                         'Try git rebase (--continue | --abort | --skip)'
 345         fi
 346 fi
 347
 348 # The tree must be really really clean.
 349 if ! git update-index --ignore-submodules --refresh; then
 350         echo >&2 "cannot rebase: you have unstaged changes"
 351         exit 1
 352 fi
 353 diff=$(git diff-index --cached --name-status -r --ignore-submodules HEAD --)
 354 case "$diff" in
 355 ?*)     echo >&2 "cannot rebase: your index contains uncommitted changes"
 356         echo >&2 "$diff"
 357         exit 1
 358         ;;
 359 esac
 360
 361 if test -z "$rebase_root"
 362 then
 363         # The upstream head must be given.  Make sure it is valid.
 364         upstream_name="$1"
 365         shift
 366         upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 367         die "invalid upstream $upstream_name"
 368         unset root_flag
 369         upstream_arg="$upstream_name"
 370 else
 371         test -z "$newbase" && die "--root must be used with --onto"
 372         unset upstream_name
 373         unset upstream
 374         root_flag="--root"
 375         upstream_arg="$root_flag"
 376 fi
 377
 378 # Make sure the branch to rebase onto is valid.
 379 onto_name=${newbase-"$upstream_name"}
 380 onto=$(git rev-parse --verify "${onto_name}^0") || exit
 381
 382 # If a hook exists, give it a chance to interrupt
 383 run_pre_rebase_hook "$upstream_arg" "$@"
 384
 385 # If the branch to rebase is given, that is the branch we will rebase
 386 # $branch_name -- branch being rebased, or HEAD (already detached)
 387 # $orig_head -- commit object name of tip of the branch before rebasing
 388 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
 389 switch_to=
 390 case "$#" in
 391 1)
 392         # Is it "rebase other $branchname" or "rebase other $commit"?
 393         branch_name="$1"
 394         switch_to="$1"
 395
 396         if git show-ref --verify --quiet -- "refs/heads/$1" &&
 397            branch=$(git rev-parse -q --verify "refs/heads/$1")
 398         then
 399                 head_name="refs/heads/$1"
 400         elif branch=$(git rev-parse -q --verify "$1")
 401         then
 402                 head_name="detached HEAD"
 403         else
 404                 usage
 405         fi
 406         ;;
 407 *)
 408         # Do not need to switch branches, we are already on it.
 409         if branch_name=`git symbolic-ref -q HEAD`
 410         then
 411                 head_name=$branch_name
 412                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 413         else
 414                 head_name="detached HEAD"
 415                 branch_name=HEAD ;# detached
 416         fi
 417         branch=$(git rev-parse --verify "${branch_name}^0") || exit
 418         ;;
 419 esac
 420 orig_head=$branch
 421
 422 # Now we are rebasing commits $upstream..$branch (or with --root,
 423 # everything leading up to $branch) on top of $onto
 424
 425 # Check if we are already based on $onto with linear history,
 426 # but this should be done only when upstream and onto are the same.
 427 mb=$(git merge-base "$onto" "$branch")
 428 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
 429         # linear history?
 430         ! (git rev-list --parents "$onto".."$branch" | grep " .* ") > /dev/null
 431 then
 432         if test -z "$force_rebase"
 433         then
 434                 # Lazily switch to the target branch if needed...
 435                 test -z "$switch_to" || git checkout "$switch_to"
 436                 echo >&2 "Current branch $branch_name is up to date."
 437                 exit 0
 438         else
 439                 echo "Current branch $branch_name is up to date, rebase forced."
 440         fi
 441 fi
 442
 443 if test -n "$verbose"
 444 then
 445         echo "Changes from $mb to $onto:"
 446         # We want color (if set), but no pager
 447         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 448 fi
 449
 450 # Detach HEAD and reset the tree
 451 echo "First, rewinding head to replay your work on top of it..."
 452 git checkout -q "$onto^0" || die "could not detach HEAD"
 453 git update-ref ORIG_HEAD $branch
 454
 455 # If the $onto is a proper descendant of the tip of the branch, then
 456 # we just fast forwarded.
 457 if test "$mb" = "$branch"
 458 then
 459         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 460         move_to_original_branch
 461         exit 0
 462 fi
 463
 464 if test -n "$rebase_root"
 465 then
 466         revisions="$onto..$orig_head"
 467 else
 468         revisions="$upstream..$orig_head"
 469 fi
 470
 471 if test -z "$do_merge"
 472 then
 473         git format-patch -k --stdout --full-index --ignore-if-in-upstream \
 474                 $root_flag "$revisions" |
 475         git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
 476         move_to_original_branch
 477         ret=$?
 478         test 0 != $ret -a -d "$GIT_DIR"/rebase-apply &&
 479                 echo $head_name > "$GIT_DIR"/rebase-apply/head-name &&
 480                 echo $onto > "$GIT_DIR"/rebase-apply/onto &&
 481                 echo $orig_head > "$GIT_DIR"/rebase-apply/orig-head
 482         exit $ret
 483 fi
 484
 485 # start doing a rebase with git-merge
 486 # this is rename-aware if the recursive (default) strategy is used
 487
 488 mkdir -p "$dotest"
 489 echo "$onto" > "$dotest/onto"
 490 echo "$onto_name" > "$dotest/onto_name"
 491 prev_head=$orig_head
 492 echo "$prev_head" > "$dotest/prev_head"
 493 echo "$orig_head" > "$dotest/orig-head"
 494 echo "$head_name" > "$dotest/head-name"
 495
 496 msgnum=0
 497 for cmt in `git rev-list --reverse --no-merges "$revisions"`
 498 do
 499         msgnum=$(($msgnum + 1))
 500         echo "$cmt" > "$dotest/cmt.$msgnum"
 501 done
 502
 503 echo 1 >"$dotest/msgnum"
 504 echo $msgnum >"$dotest/end"
 505
 506 end=$msgnum
 507 msgnum=1
 508
 509 while test "$msgnum" -le "$end"
 510 do
 511         call_merge "$msgnum"
 512         continue_merge
 513 done
 514
 515 finish_rb_merge