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=$(git symbolic-ref HEAD)
  91         msgnum=$(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 $cmt"
 114                 ;;
 115         esac
 116 }
 117
 118 finish_rb_merge () {
 119         if test -f "$dotest/stash"
 120         then
 121                 stash=$(cat "$dotest/stash")
 122                 git stash apply --index "$stash"
 123         fi
 124         rm -r "$dotest"
 125         echo "All done."
 126 }
 127
 128 read_stash () {
 129         if test -f "$1"
 130         then
 131                 cat "$1"
 132         fi
 133 }
 134 unstash_and_exit () {
 135         err=$?
 136         if test -f "$1" && test $err = 0
 137         then
 138                 git stash apply --index "$1"
 139         fi
 140         exit $err
 141 }
 142
 143 is_interactive () {
 144         test -f "$dotest"/interactive ||
 145         while case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
 146         do
 147                 shift
 148         done && test -n "$1"
 149 }
 150
 151 is_interactive "$@" && exec git-rebase--interactive "$@"
 152
 153 while case "$#" in 0) break ;; esac
 154 do
 155         case "$1" in
 156         --continue)
 157                 git diff-files --quiet || {
 158                         echo "You must edit all merge conflicts and then"
 159                         echo "mark them as resolved using git add"
 160                         exit 1
 161                 }
 162                 if test -d "$dotest"
 163                 then
 164                         prev_head="`cat $dotest/prev_head`"
 165                         end="`cat $dotest/end`"
 166                         msgnum="`cat $dotest/msgnum`"
 167                         onto="`cat $dotest/onto`"
 168                         continue_merge
 169                         while test "$msgnum" -le "$end"
 170                         do
 171                                 call_merge "$msgnum"
 172                                 continue_merge
 173                         done
 174                         finish_rb_merge
 175                         exit
 176                 fi
 177                 stash=$(read_stash ".dotest/stash")
 178                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
 179                 unstash_and_exit "$stash"
 180                 ;;
 181         --skip)
 182                 if test -d "$dotest"
 183                 then
 184                         git rerere clear
 185                         prev_head="`cat $dotest/prev_head`"
 186                         end="`cat $dotest/end`"
 187                         msgnum="`cat $dotest/msgnum`"
 188                         msgnum=$(($msgnum + 1))
 189                         onto="`cat $dotest/onto`"
 190                         while test "$msgnum" -le "$end"
 191                         do
 192                                 call_merge "$msgnum"
 193                                 continue_merge
 194                         done
 195                         finish_rb_merge
 196                         exit
 197                 fi
 198                 stash=$(read_stash ".dotest/stash")
 199                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
 200                 unstash_and_exit "$stash"
 201                 ;;
 202         --abort)
 203                 git rerere clear
 204                 if test -d "$dotest"
 205                 then
 206                         if test -f "$dotest/stash"
 207                         then
 208                                 stash=$(cat "$dotest/stash")
 209                         fi
 210                         rm -r "$dotest"
 211                 elif test -d .dotest
 212                 then
 213                         if test -f ".dotest/stash"
 214                         then
 215                                 stash=$(cat ".dotest/stash")
 216                         fi
 217                         rm -r .dotest
 218                 else
 219                         die "No rebase in progress?"
 220                 fi
 221                 git reset --hard ORIG_HEAD
 222                 test -z "$stash" || git stash apply --index "$stash"
 223                 exit
 224                 ;;
 225         --onto)
 226                 test 2 -le "$#" || usage
 227                 newbase="$2"
 228                 shift
 229                 ;;
 230         -M|-m|--m|--me|--mer|--merg|--merge)
 231                 do_merge=t
 232                 ;;
 233         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 234                 --strateg=*|--strategy=*|\
 235         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 236                 case "$#,$1" in
 237                 *,*=*)
 238                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 239                 1,*)
 240                         usage ;;
 241                 *)
 242                         strategy="$2"
 243                         shift ;;
 244                 esac
 245                 do_merge=t
 246                 ;;
 247         -v|--verbose)
 248                 verbose=t
 249                 ;;
 250         --whitespace=*)
 251                 git_am_opt="$git_am_opt $1"
 252                 ;;
 253         -C*)
 254                 git_am_opt="$git_am_opt $1"
 255                 ;;
 256         -*)
 257                 usage
 258                 ;;
 259         *)
 260                 break
 261                 ;;
 262         esac
 263         shift
 264 done
 265
 266 # Make sure we do not have .dotest
 267 if test -z "$do_merge"
 268 then
 269         if mkdir .dotest
 270         then
 271                 rmdir .dotest
 272         else
 273                 echo >&2 '
 274 It seems that I cannot create a .dotest directory, and I wonder if you
 275 are in the middle of patch application or another rebase.  If that is not
 276 the case, please rm -fr .dotest and run me again.  I am stopping in case
 277 you still have something valuable there.'
 278                 exit 1
 279         fi
 280 else
 281         if test -d "$dotest"
 282         then
 283                 die "previous dotest directory $dotest still exists." \
 284                         'try git-rebase < --continue | --abort >'
 285         fi
 286 fi
 287
 288 # The upstream head must be given.  Make sure it is valid.
 289 upstream_name="$1"
 290 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 291     die "invalid upstream $upstream_name"
 292
 293 # Make sure the branch to rebase onto is valid.
 294 onto_name=${newbase-"$upstream_name"}
 295 onto=$(git rev-parse --verify "${onto_name}^0") || exit
 296
 297 # The tree must be clean enough for us to create a stash
 298 stash=$(git stash create) || exit
 299 if test -n "$stash"
 300 then
 301         echo >&2 "Stashed away your working tree changes"
 302 fi
 303
 304 # If a hook exists, give it a chance to interrupt
 305 if test -x "$GIT_DIR/hooks/pre-rebase"
 306 then
 307         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 308                 echo >&2 "The pre-rebase hook refused to rebase."
 309                 test -z "$stash" || git stash apply --index "$stash"
 310                 exit 1
 311         }
 312 fi
 313
 314 # If the branch to rebase is given, first switch to it.
 315 case "$#" in
 316 2)
 317         branch_name="$2"
 318         git-checkout "$2" || {
 319                 test -z "$stash" || git stash apply --index "$stash"
 320                 usage
 321         }
 322         ;;
 323 *)
 324         if branch_name=`git symbolic-ref -q HEAD`
 325         then
 326                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 327         else
 328                 branch_name=HEAD ;# detached
 329         fi
 330         ;;
 331 esac
 332 branch=$(git rev-parse --verify "${branch_name}^0") || exit
 333
 334 # Now we are rebasing commits $upstream..$branch on top of $onto
 335
 336 # Check if we are already based on $onto with linear history,
 337 # but this should be done only when upstream and onto are the same.
 338 mb=$(git merge-base "$onto" "$branch")
 339 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
 340         # linear history?
 341         ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
 342 then
 343         echo >&2 "Current branch $branch_name is up to date."
 344         test -z "$stash" || git stash apply --index "$stash"
 345         exit 0
 346 fi
 347
 348 if test -n "$verbose"
 349 then
 350         echo "Changes from $mb to $onto:"
 351         # We want color (if set), but no pager
 352         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 353 fi
 354
 355 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
 356 echo "First, rewinding head to replay your work on top of it..."
 357 git-reset --hard "$onto"
 358
 359 # If the $onto is a proper descendant of the tip of the branch, then
 360 # we just fast forwarded.
 361 if test "$mb" = "$branch"
 362 then
 363         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 364         test -z "$stash" || git stash apply --index "$stash"
 365         exit 0
 366 fi
 367
 368 if test -z "$do_merge"
 369 then
 370         git format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
 371         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG"
 372         err=$?
 373
 374         if test $err = 0
 375         then
 376                 test -z "$stash" || git stash apply --index "$stash"
 377                 exit
 378         else
 379                 test -z "$stash" || echo "$stash" >.dotest/stash
 380                 exit $err
 381         fi
 382 fi
 383
 384 # start doing a rebase with git-merge
 385 # this is rename-aware if the recursive (default) strategy is used
 386
 387 mkdir -p "$dotest"
 388 echo "$onto" > "$dotest/onto"
 389 echo "$onto_name" > "$dotest/onto_name"
 390 prev_head=`git rev-parse HEAD^0`
 391 echo "$prev_head" > "$dotest/prev_head"
 392 test -z "$stash" || echo "$stash" >"$dotest/stash"
 393
 394 msgnum=0
 395 for cmt in `git rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
 396 do
 397         msgnum=$(($msgnum + 1))
 398         echo "$cmt" > "$dotest/cmt.$msgnum"
 399 done
 400
 401 echo 1 >"$dotest/msgnum"
 402 echo $msgnum >"$dotest/end"
 403
 404 end=$msgnum
 405 msgnum=1
 406
 407 while test "$msgnum" -le "$end"
 408 do
 409         call_merge "$msgnum"
 410         continue_merge
 411 done
 412
 413 finish_rb_merge