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