git-rebase.sh

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