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.
  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=$GIT_DIR/.dotest-merge
  46 prec=4
  47 verbose=
  48 git_am_opt=
  49
  50 continue_merge () {
  51         test -n "$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 "$1"
 145 }
 146
 147 is_interactive "$@" && exec git-rebase--interactive "$@"
 148
 149 while test $# != 0
 150 do
 151         case "$1" in
 152         --continue)
 153                 test -d "$dotest" -o -d .dotest ||
 154                         die "No rebase in progress?"
 155
 156                 git diff-files --quiet --ignore-submodules || {
 157                         echo "You must edit all merge conflicts and then"
 158                         echo "mark them as resolved using git add"
 159                         exit 1
 160                 }
 161                 if test -d "$dotest"
 162                 then
 163                         prev_head=$(cat "$dotest/prev_head")
 164                         end=$(cat "$dotest/end")
 165                         msgnum=$(cat "$dotest/msgnum")
 166                         onto=$(cat "$dotest/onto")
 167                         continue_merge
 168                         while test "$msgnum" -le "$end"
 169                         do
 170                                 call_merge "$msgnum"
 171                                 continue_merge
 172                         done
 173                         finish_rb_merge
 174                         exit
 175                 fi
 176                 head_name=$(cat .dotest/head-name) &&
 177                 onto=$(cat .dotest/onto) &&
 178                 orig_head=$(cat .dotest/orig-head) &&
 179                 git am --resolved --3way --resolvemsg="$RESOLVEMSG" &&
 180                 move_to_original_branch
 181                 exit
 182                 ;;
 183         --skip)
 184                 test -d "$dotest" -o -d .dotest ||
 185                         die "No rebase in progress?"
 186
 187                 git reset --hard HEAD || exit $?
 188                 if test -d "$dotest"
 189                 then
 190                         git rerere clear
 191                         prev_head=$(cat "$dotest/prev_head")
 192                         end=$(cat "$dotest/end")
 193                         msgnum=$(cat "$dotest/msgnum")
 194                         msgnum=$(($msgnum + 1))
 195                         onto=$(cat "$dotest/onto")
 196                         while test "$msgnum" -le "$end"
 197                         do
 198                                 call_merge "$msgnum"
 199                                 continue_merge
 200                         done
 201                         finish_rb_merge
 202                         exit
 203                 fi
 204                 head_name=$(cat .dotest/head-name) &&
 205                 onto=$(cat .dotest/onto) &&
 206                 orig_head=$(cat .dotest/orig-head) &&
 207                 git am -3 --skip --resolvemsg="$RESOLVEMSG" &&
 208                 move_to_original_branch
 209                 exit
 210                 ;;
 211         --abort)
 212                 test -d "$dotest" -o -d .dotest ||
 213                         die "No rebase in progress?"
 214
 215                 git rerere clear
 216                 if test -d "$dotest"
 217                 then
 218                         move_to_original_branch
 219                 else
 220                         dotest=.dotest
 221                         move_to_original_branch
 222                 fi
 223                 git reset --hard $(cat "$dotest/orig-head")
 224                 rm -r "$dotest"
 225                 exit
 226                 ;;
 227         --onto)
 228                 test 2 -le "$#" || usage
 229                 newbase="$2"
 230                 shift
 231                 ;;
 232         -M|-m|--m|--me|--mer|--merg|--merge)
 233                 do_merge=t
 234                 ;;
 235         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 236                 --strateg=*|--strategy=*|\
 237         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 238                 case "$#,$1" in
 239                 *,*=*)
 240                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 241                 1,*)
 242                         usage ;;
 243                 *)
 244                         strategy="$2"
 245                         shift ;;
 246                 esac
 247                 do_merge=t
 248                 ;;
 249         -v|--verbose)
 250                 verbose=t
 251                 ;;
 252         --whitespace=*)
 253                 git_am_opt="$git_am_opt $1"
 254                 ;;
 255         -C*)
 256                 git_am_opt="$git_am_opt $1"
 257                 ;;
 258         -*)
 259                 usage
 260                 ;;
 261         *)
 262                 break
 263                 ;;
 264         esac
 265         shift
 266 done
 267
 268 # Make sure we do not have .dotest
 269 if test -z "$do_merge"
 270 then
 271         if mkdir .dotest
 272         then
 273                 rmdir .dotest
 274         else
 275                 echo >&2 '
 276 It seems that I cannot create a .dotest directory, and I wonder if you
 277 are in the middle of patch application or another rebase.  If that is not
 278 the case, please rm -fr .dotest and run me again.  I am stopping in case
 279 you still have something valuable there.'
 280                 exit 1
 281         fi
 282 else
 283         if test -d "$dotest"
 284         then
 285                 die "previous dotest directory $dotest still exists." \
 286                         'try git-rebase < --continue | --abort >'
 287         fi
 288 fi
 289
 290 # The tree must be really really clean.
 291 git update-index --ignore-submodules --refresh || exit
 292 diff=$(git diff-index --cached --name-status -r --ignore-submodules HEAD --)
 293 case "$diff" in
 294 ?*)     echo "cannot rebase: your index is not up-to-date"
 295         echo "$diff"
 296         exit 1
 297         ;;
 298 esac
 299
 300 # The upstream head must be given.  Make sure it is valid.
 301 upstream_name="$1"
 302 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 303     die "invalid upstream $upstream_name"
 304
 305 # Make sure the branch to rebase onto is valid.
 306 onto_name=${newbase-"$upstream_name"}
 307 onto=$(git rev-parse --verify "${onto_name}^0") || exit
 308
 309 # If a hook exists, give it a chance to interrupt
 310 if test -x "$GIT_DIR/hooks/pre-rebase"
 311 then
 312         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 313                 echo >&2 "The pre-rebase hook refused to rebase."
 314                 exit 1
 315         }
 316 fi
 317
 318 # If the branch to rebase is given, that is the branch we will rebase
 319 # $branch_name -- branch being rebased, or HEAD (already detached)
 320 # $orig_head -- commit object name of tip of the branch before rebasing
 321 # $head_name -- refs/heads/<that-branch> or "detached HEAD"
 322 switch_to=
 323 case "$#" in
 324 2)
 325         # Is it "rebase other $branchname" or "rebase other $commit"?
 326         branch_name="$2"
 327         switch_to="$2"
 328
 329         if git show-ref --verify --quiet -- "refs/heads/$2" &&
 330            branch=$(git rev-parse --verify "refs/heads/$2" 2>/dev/null)
 331         then
 332                 head_name="refs/heads/$2"
 333         elif branch=$(git rev-parse --verify "$2" 2>/dev/null)
 334         then
 335                 head_name="detached HEAD"
 336         else
 337                 usage
 338         fi
 339         ;;
 340 *)
 341         # Do not need to switch branches, we are already on it.
 342         if branch_name=`git symbolic-ref -q HEAD`
 343         then
 344                 head_name=$branch_name
 345                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 346         else
 347                 head_name="detached HEAD"
 348                 branch_name=HEAD ;# detached
 349         fi
 350         branch=$(git rev-parse --verify "${branch_name}^0") || exit
 351         ;;
 352 esac
 353 orig_head=$branch
 354
 355 # Now we are rebasing commits $upstream..$branch on top of $onto
 356
 357 # Check if we are already based on $onto with linear history,
 358 # but this should be done only when upstream and onto are the same.
 359 mb=$(git merge-base "$onto" "$branch")
 360 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
 361         # linear history?
 362         ! (git rev-list --parents "$onto".."$branch" | grep " .* ") > /dev/null
 363 then
 364         # Lazily switch to the target branch if needed...
 365         test -z "$switch_to" || git checkout "$switch_to"
 366         echo >&2 "Current branch $branch_name is up to date."
 367         exit 0
 368 fi
 369
 370 if test -n "$verbose"
 371 then
 372         echo "Changes from $mb to $onto:"
 373         # We want color (if set), but no pager
 374         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 375 fi
 376
 377 # Detach HEAD and reset the tree
 378 echo "First, rewinding head to replay your work on top of it..."
 379 git checkout "$onto^0" >/dev/null 2>&1 ||
 380         die "could not detach HEAD"
 381 # git reset --hard "$onto^0"
 382
 383 # If the $onto is a proper descendant of the tip of the branch, then
 384 # we just fast forwarded.
 385 if test "$mb" = "$branch"
 386 then
 387         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 388         move_to_original_branch
 389         exit 0
 390 fi
 391
 392 if test -z "$do_merge"
 393 then
 394         git format-patch -k --stdout --full-index --ignore-if-in-upstream \
 395                 "$upstream..$orig_head" |
 396         git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
 397         move_to_original_branch
 398         ret=$?
 399         test 0 != $ret -a -d .dotest &&
 400                 echo $head_name > .dotest/head-name &&
 401                 echo $onto > .dotest/onto &&
 402                 echo $orig_head > .dotest/orig-head
 403         exit $ret
 404 fi
 405
 406 # start doing a rebase with git-merge
 407 # this is rename-aware if the recursive (default) strategy is used
 408
 409 mkdir -p "$dotest"
 410 echo "$onto" > "$dotest/onto"
 411 echo "$onto_name" > "$dotest/onto_name"
 412 prev_head=$orig_head
 413 echo "$prev_head" > "$dotest/prev_head"
 414 echo "$orig_head" > "$dotest/orig-head"
 415 echo "$head_name" > "$dotest/head-name"
 416
 417 msgnum=0
 418 for cmt in `git rev-list --reverse --no-merges "$upstream..$orig_head"`
 419 do
 420         msgnum=$(($msgnum + 1))
 421         echo "$cmt" > "$dotest/cmt.$msgnum"
 422 done
 423
 424 echo 1 >"$dotest/msgnum"
 425 echo $msgnum >"$dotest/end"
 426
 427 end=$msgnum
 428 msgnum=1
 429
 430 while test "$msgnum" -le "$end"
 431 do
 432         call_merge "$msgnum"
 433         continue_merge
 434 done
 435
 436 finish_rb_merge