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         if ! git diff-index --quiet HEAD
  63         then
  64                 if ! git-commit -C "`cat $dotest/current`"
  65                 then
  66                         echo "Commit failed, please do not call \"git commit\""
  67                         echo "directly, but instead do one of the following: "
  68                         die "$RESOLVEMSG"
  69                 fi
  70                 printf "Committed: %0${prec}d" $msgnum
  71         else
  72                 printf "Already applied: %0${prec}d" $msgnum
  73         fi
  74         echo ' '`git rev-list --pretty=oneline -1 HEAD | \
  75                                 sed 's/^[a-f0-9]\+ //'`
  76
  77         prev_head=`git rev-parse HEAD^0`
  78         # save the resulting commit so we can read-tree on it later
  79         echo "$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 $cmt"
 114                 ;;
 115         esac
 116 }
 117
 118 finish_rb_merge () {
 119         rm -r "$dotest"
 120         echo "All done."
 121 }
 122
 123 is_interactive () {
 124         test -f "$dotest"/interactive ||
 125         while case $#,"$1" in 0,|*,-i|*,--interactive) break ;; esac
 126         do
 127                 shift
 128         done && test -n "$1"
 129 }
 130
 131 is_interactive "$@" && exec git-rebase--interactive "$@"
 132
 133 while case "$#" in 0) break ;; esac
 134 do
 135         case "$1" in
 136         --continue)
 137                 git diff-files --quiet || {
 138                         echo "You must edit all merge conflicts and then"
 139                         echo "mark them as resolved using git add"
 140                         exit 1
 141                 }
 142                 if test -d "$dotest"
 143                 then
 144                         prev_head="`cat $dotest/prev_head`"
 145                         end="`cat $dotest/end`"
 146                         msgnum="`cat $dotest/msgnum`"
 147                         onto="`cat $dotest/onto`"
 148                         continue_merge
 149                         while test "$msgnum" -le "$end"
 150                         do
 151                                 call_merge "$msgnum"
 152                                 continue_merge
 153                         done
 154                         finish_rb_merge
 155                         exit
 156                 fi
 157                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
 158                 exit
 159                 ;;
 160         --skip)
 161                 if test -d "$dotest"
 162                 then
 163                         git rerere clear
 164                         prev_head="`cat $dotest/prev_head`"
 165                         end="`cat $dotest/end`"
 166                         msgnum="`cat $dotest/msgnum`"
 167                         msgnum=$(($msgnum + 1))
 168                         onto="`cat $dotest/onto`"
 169                         while test "$msgnum" -le "$end"
 170                         do
 171                                 call_merge "$msgnum"
 172                                 continue_merge
 173                         done
 174                         finish_rb_merge
 175                         exit
 176                 fi
 177                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
 178                 exit
 179                 ;;
 180         --abort)
 181                 git rerere clear
 182                 if test -d "$dotest"
 183                 then
 184                         rm -r "$dotest"
 185                 elif test -d .dotest
 186                 then
 187                         rm -r .dotest
 188                 else
 189                         die "No rebase in progress?"
 190                 fi
 191                 git reset --hard ORIG_HEAD
 192                 exit
 193                 ;;
 194         --onto)
 195                 test 2 -le "$#" || usage
 196                 newbase="$2"
 197                 shift
 198                 ;;
 199         -M|-m|--m|--me|--mer|--merg|--merge)
 200                 do_merge=t
 201                 ;;
 202         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 203                 --strateg=*|--strategy=*|\
 204         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 205                 case "$#,$1" in
 206                 *,*=*)
 207                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 208                 1,*)
 209                         usage ;;
 210                 *)
 211                         strategy="$2"
 212                         shift ;;
 213                 esac
 214                 do_merge=t
 215                 ;;
 216         -v|--verbose)
 217                 verbose=t
 218                 ;;
 219         -C*)
 220                 git_am_opt=$1
 221                 shift
 222                 ;;
 223         -*)
 224                 usage
 225                 ;;
 226         *)
 227                 break
 228                 ;;
 229         esac
 230         shift
 231 done
 232
 233 # Make sure we do not have .dotest
 234 if test -z "$do_merge"
 235 then
 236         if mkdir .dotest
 237         then
 238                 rmdir .dotest
 239         else
 240                 echo >&2 '
 241 It seems that I cannot create a .dotest directory, and I wonder if you
 242 are in the middle of patch application or another rebase.  If that is not
 243 the case, please rm -fr .dotest and run me again.  I am stopping in case
 244 you still have something valuable there.'
 245                 exit 1
 246         fi
 247 else
 248         if test -d "$dotest"
 249         then
 250                 die "previous dotest directory $dotest still exists." \
 251                         'try git-rebase < --continue | --abort >'
 252         fi
 253 fi
 254
 255 # The tree must be really really clean.
 256 git update-index --refresh || exit
 257 diff=$(git diff-index --cached --name-status -r HEAD)
 258 case "$diff" in
 259 ?*)     echo "cannot rebase: your index is not up-to-date"
 260         echo "$diff"
 261         exit 1
 262         ;;
 263 esac
 264
 265 # The upstream head must be given.  Make sure it is valid.
 266 upstream_name="$1"
 267 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 268     die "invalid upstream $upstream_name"
 269
 270 # Make sure the branch to rebase onto is valid.
 271 onto_name=${newbase-"$upstream_name"}
 272 onto=$(git rev-parse --verify "${onto_name}^0") || exit
 273
 274 # If a hook exists, give it a chance to interrupt
 275 if test -x "$GIT_DIR/hooks/pre-rebase"
 276 then
 277         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 278                 echo >&2 "The pre-rebase hook refused to rebase."
 279                 exit 1
 280         }
 281 fi
 282
 283 # If the branch to rebase is given, first switch to it.
 284 case "$#" in
 285 2)
 286         branch_name="$2"
 287         git-checkout "$2" || usage
 288         ;;
 289 *)
 290         if branch_name=`git symbolic-ref -q HEAD`
 291         then
 292                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 293         else
 294                 branch_name=HEAD ;# detached
 295         fi
 296         ;;
 297 esac
 298 branch=$(git rev-parse --verify "${branch_name}^0") || exit
 299
 300 # Now we are rebasing commits $upstream..$branch on top of $onto
 301
 302 # Check if we are already based on $onto with linear history,
 303 # but this should be done only when upstream and onto are the same.
 304 mb=$(git merge-base "$onto" "$branch")
 305 if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
 306         # linear history?
 307         ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
 308 then
 309         echo >&2 "Current branch $branch_name is up to date."
 310         exit 0
 311 fi
 312
 313 if test -n "$verbose"
 314 then
 315         echo "Changes from $mb to $onto:"
 316         # We want color (if set), but no pager
 317         GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 318 fi
 319
 320 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
 321 echo "First, rewinding head to replay your work on top of it..."
 322 git-reset --hard "$onto"
 323
 324 # If the $onto is a proper descendant of the tip of the branch, then
 325 # we just fast forwarded.
 326 if test "$mb" = "$branch"
 327 then
 328         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 329         exit 0
 330 fi
 331
 332 if test -z "$do_merge"
 333 then
 334         git format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
 335         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG"
 336         exit $?
 337 fi
 338
 339 # start doing a rebase with git-merge
 340 # this is rename-aware if the recursive (default) strategy is used
 341
 342 mkdir -p "$dotest"
 343 echo "$onto" > "$dotest/onto"
 344 echo "$onto_name" > "$dotest/onto_name"
 345 prev_head=`git rev-parse HEAD^0`
 346 echo "$prev_head" > "$dotest/prev_head"
 347
 348 msgnum=0
 349 for cmt in `git rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
 350 do
 351         msgnum=$(($msgnum + 1))
 352         echo "$cmt" > "$dotest/cmt.$msgnum"
 353 done
 354
 355 echo 1 >"$dotest/msgnum"
 356 echo $msgnum >"$dotest/end"
 357
 358 end=$msgnum
 359 msgnum=1
 360
 361 while test "$msgnum" -le "$end"
 362 do
 363         call_merge "$msgnum"
 364         continue_merge
 365 done
 366
 367 finish_rb_merge