contrib/subtree/git-subtree.sh

   1 #!/bin/sh
   2 #
   3 # git-subtree.sh: split/join git repositories in subdirectories of this one
   4 #
   5 # Copyright (C) 2009 Avery Pennarun <apenwarr@gmail.com>
   6 #
   7 if [ $# -eq 0 ]; then
   8     set -- -h
   9 fi
  10 OPTS_SPEC="\
  11 git subtree add   --prefix=<prefix> <commit>
  12 git subtree add   --prefix=<prefix> <repository> <ref>
  13 git subtree merge --prefix=<prefix> <commit>
  14 git subtree pull  --prefix=<prefix> <repository> <ref>
  15 git subtree push  --prefix=<prefix> <repository> <ref>
  16 git subtree split --prefix=<prefix> <commit...>
  17 --
  18 h,help        show the help
  19 q             quiet
  20 d             show debug messages
  21 P,prefix=     the name of the subdir to split out
  22 m,message=    use the given message as the commit message for the merge commit
  23  options for 'split'
  24 annotate=     add a prefix to commit message of new commits
  25 b,branch=     create a new branch from the split subtree
  26 ignore-joins  ignore prior --rejoin commits
  27 onto=         try connecting new tree to an existing one
  28 rejoin        merge the new branch back into HEAD
  29  options for 'add', 'merge', and 'pull'
  30 squash        merge subtree changes as a single commit
  31 "
  32 eval "$(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)"
  33
  34 PATH=$PATH:$(git --exec-path)
  35 . git-sh-setup
  36
  37 require_work_tree
  38
  39 quiet=
  40 branch=
  41 debug=
  42 command=
  43 onto=
  44 rejoin=
  45 ignore_joins=
  46 annotate=
  47 squash=
  48 message=
  49 prefix=
  50
  51 debug()
  52 {
  53         if [ -n "$debug" ]; then
  54                 printf "%s\n" "$*" >&2
  55         fi
  56 }
  57
  58 say()
  59 {
  60         if [ -z "$quiet" ]; then
  61                 printf "%s\n" "$*" >&2
  62         fi
  63 }
  64
  65 progress()
  66 {
  67         if [ -z "$quiet" ]; then
  68                 printf "%s\r" "$*" >&2
  69         fi
  70 }
  71
  72 assert()
  73 {
  74         if "$@"; then
  75                 :
  76         else
  77                 die "assertion failed: " "$@"
  78         fi
  79 }
  80
  81
  82 #echo "Options: $*"
  83
  84 while [ $# -gt 0 ]; do
  85         opt="$1"
  86         shift
  87         case "$opt" in
  88                 -q) quiet=1 ;;
  89                 -d) debug=1 ;;
  90                 --annotate) annotate="$1"; shift ;;
  91                 --no-annotate) annotate= ;;
  92                 -b) branch="$1"; shift ;;
  93                 -P) prefix="${1%/}"; shift ;;
  94                 -m) message="$1"; shift ;;
  95                 --no-prefix) prefix= ;;
  96                 --onto) onto="$1"; shift ;;
  97                 --no-onto) onto= ;;
  98                 --rejoin) rejoin=1 ;;
  99                 --no-rejoin) rejoin= ;;
 100                 --ignore-joins) ignore_joins=1 ;;
 101                 --no-ignore-joins) ignore_joins= ;;
 102                 --squash) squash=1 ;;
 103                 --no-squash) squash= ;;
 104                 --) break ;;
 105                 *) die "Unexpected option: $opt" ;;
 106         esac
 107 done
 108
 109 command="$1"
 110 shift
 111 case "$command" in
 112         add|merge|pull) default= ;;
 113         split|push) default="--default HEAD" ;;
 114         *) die "Unknown command '$command'" ;;
 115 esac
 116
 117 if [ -z "$prefix" ]; then
 118         die "You must provide the --prefix option."
 119 fi
 120
 121 case "$command" in
 122         add) [ -e "$prefix" ] &&
 123                 die "prefix '$prefix' already exists." ;;
 124         *)   [ -e "$prefix" ] ||
 125                 die "'$prefix' does not exist; use 'git subtree add'" ;;
 126 esac
 127
 128 dir="$(dirname "$prefix/.")"
 129
 130 if [ "$command" != "pull" -a "$command" != "add" -a "$command" != "push" ]; then
 131         revs=$(git rev-parse $default --revs-only "$@") || exit $?
 132         dirs="$(git rev-parse --no-revs --no-flags "$@")" || exit $?
 133         if [ -n "$dirs" ]; then
 134                 die "Error: Use --prefix instead of bare filenames."
 135         fi
 136 fi
 137
 138 debug "command: {$command}"
 139 debug "quiet: {$quiet}"
 140 debug "revs: {$revs}"
 141 debug "dir: {$dir}"
 142 debug "opts: {$*}"
 143 debug
 144
 145 cache_setup()
 146 {
 147         cachedir="$GIT_DIR/subtree-cache/$$"
 148         rm -rf "$cachedir" || die "Can't delete old cachedir: $cachedir"
 149         mkdir -p "$cachedir" || die "Can't create new cachedir: $cachedir"
 150         mkdir -p "$cachedir/notree" || die "Can't create new cachedir: $cachedir/notree"
 151         debug "Using cachedir: $cachedir" >&2
 152 }
 153
 154 cache_get()
 155 {
 156         for oldrev in $*; do
 157                 if [ -r "$cachedir/$oldrev" ]; then
 158                         read newrev <"$cachedir/$oldrev"
 159                         echo $newrev
 160                 fi
 161         done
 162 }
 163
 164 cache_miss()
 165 {
 166         for oldrev in $*; do
 167                 if [ ! -r "$cachedir/$oldrev" ]; then
 168                         echo $oldrev
 169                 fi
 170         done
 171 }
 172
 173 check_parents()
 174 {
 175         missed=$(cache_miss $*)
 176         for miss in $missed; do
 177                 if [ ! -r "$cachedir/notree/$miss" ]; then
 178                         debug "  incorrect order: $miss"
 179                 fi
 180         done
 181 }
 182
 183 set_notree()
 184 {
 185         echo "1" > "$cachedir/notree/$1"
 186 }
 187
 188 cache_set()
 189 {
 190         oldrev="$1"
 191         newrev="$2"
 192         if [ "$oldrev" != "latest_old" \
 193              -a "$oldrev" != "latest_new" \
 194              -a -e "$cachedir/$oldrev" ]; then
 195                 die "cache for $oldrev already exists!"
 196         fi
 197         echo "$newrev" >"$cachedir/$oldrev"
 198 }
 199
 200 rev_exists()
 201 {
 202         if git rev-parse "$1" >/dev/null 2>&1; then
 203                 return 0
 204         else
 205                 return 1
 206         fi
 207 }
 208
 209 rev_is_descendant_of_branch()
 210 {
 211         newrev="$1"
 212         branch="$2"
 213         branch_hash=$(git rev-parse $branch)
 214         match=$(git rev-list -1 $branch_hash ^$newrev)
 215
 216         if [ -z "$match" ]; then
 217                 return 0
 218         else
 219                 return 1
 220         fi
 221 }
 222
 223 # if a commit doesn't have a parent, this might not work.  But we only want
 224 # to remove the parent from the rev-list, and since it doesn't exist, it won't
 225 # be there anyway, so do nothing in that case.
 226 try_remove_previous()
 227 {
 228         if rev_exists "$1^"; then
 229                 echo "^$1^"
 230         fi
 231 }
 232
 233 find_latest_squash()
 234 {
 235         debug "Looking for latest squash ($dir)..."
 236         dir="$1"
 237         sq=
 238         main=
 239         sub=
 240         git log --grep="^git-subtree-dir: $dir/*\$" \
 241                 --pretty=format:'START %H%n%s%n%n%b%nEND%n' HEAD |
 242         while read a b junk; do
 243                 debug "$a $b $junk"
 244                 debug "{{$sq/$main/$sub}}"
 245                 case "$a" in
 246                         START) sq="$b" ;;
 247                         git-subtree-mainline:) main="$b" ;;
 248                         git-subtree-split:)
 249                                 sub="$(git rev-parse "$b^0")" ||
 250                                     die "could not rev-parse split hash $b from commit $sq"
 251                                 ;;
 252                         END)
 253                                 if [ -n "$sub" ]; then
 254                                         if [ -n "$main" ]; then
 255                                                 # a rejoin commit?
 256                                                 # Pretend its sub was a squash.
 257                                                 sq="$sub"
 258                                         fi
 259                                         debug "Squash found: $sq $sub"
 260                                         echo "$sq" "$sub"
 261                                         break
 262                                 fi
 263                                 sq=
 264                                 main=
 265                                 sub=
 266                                 ;;
 267                 esac
 268         done
 269 }
 270
 271 find_existing_splits()
 272 {
 273         debug "Looking for prior splits..."
 274         dir="$1"
 275         revs="$2"
 276         main=
 277         sub=
 278         git log --grep="^git-subtree-dir: $dir/*\$" \
 279                 --pretty=format:'START %H%n%s%n%n%b%nEND%n' $revs |
 280         while read a b junk; do
 281                 case "$a" in
 282                         START) sq="$b" ;;
 283                         git-subtree-mainline:) main="$b" ;;
 284                         git-subtree-split:)
 285                                 sub="$(git rev-parse "$b^0")" ||
 286                                     die "could not rev-parse split hash $b from commit $sq"
 287                                 ;;
 288                         END)
 289                                 debug "  Main is: '$main'"
 290                                 if [ -z "$main" -a -n "$sub" ]; then
 291                                         # squash commits refer to a subtree
 292                                         debug "  Squash: $sq from $sub"
 293                                         cache_set "$sq" "$sub"
 294                                 fi
 295                                 if [ -n "$main" -a -n "$sub" ]; then
 296                                         debug "  Prior: $main -> $sub"
 297                                         cache_set $main $sub
 298                                         cache_set $sub $sub
 299                                         try_remove_previous "$main"
 300                                         try_remove_previous "$sub"
 301                                 fi
 302                                 main=
 303                                 sub=
 304                                 ;;
 305                 esac
 306         done
 307 }
 308
 309 copy_commit()
 310 {
 311         # We're going to set some environment vars here, so
 312         # do it in a subshell to get rid of them safely later
 313         debug copy_commit "{$1}" "{$2}" "{$3}"
 314         git log -1 --pretty=format:'%an%n%ae%n%aD%n%cn%n%ce%n%cD%n%B' "$1" |
 315         (
 316                 read GIT_AUTHOR_NAME
 317                 read GIT_AUTHOR_EMAIL
 318                 read GIT_AUTHOR_DATE
 319                 read GIT_COMMITTER_NAME
 320                 read GIT_COMMITTER_EMAIL
 321                 read GIT_COMMITTER_DATE
 322                 export  GIT_AUTHOR_NAME \
 323                         GIT_AUTHOR_EMAIL \
 324                         GIT_AUTHOR_DATE \
 325                         GIT_COMMITTER_NAME \
 326                         GIT_COMMITTER_EMAIL \
 327                         GIT_COMMITTER_DATE
 328                 (printf "%s" "$annotate"; cat ) |
 329                 git commit-tree "$2" $3  # reads the rest of stdin
 330         ) || die "Can't copy commit $1"
 331 }
 332
 333 add_msg()
 334 {
 335         dir="$1"
 336         latest_old="$2"
 337         latest_new="$3"
 338         if [ -n "$message" ]; then
 339                 commit_message="$message"
 340         else
 341                 commit_message="Add '$dir/' from commit '$latest_new'"
 342         fi
 343         cat <<-EOF
 344                 $commit_message
 345
 346                 git-subtree-dir: $dir
 347                 git-subtree-mainline: $latest_old
 348                 git-subtree-split: $latest_new
 349         EOF
 350 }
 351
 352 add_squashed_msg()
 353 {
 354         if [ -n "$message" ]; then
 355                 echo "$message"
 356         else
 357                 echo "Merge commit '$1' as '$2'"
 358         fi
 359 }
 360
 361 rejoin_msg()
 362 {
 363         dir="$1"
 364         latest_old="$2"
 365         latest_new="$3"
 366         if [ -n "$message" ]; then
 367                 commit_message="$message"
 368         else
 369                 commit_message="Split '$dir/' into commit '$latest_new'"
 370         fi
 371         cat <<-EOF
 372                 $commit_message
 373
 374                 git-subtree-dir: $dir
 375                 git-subtree-mainline: $latest_old
 376                 git-subtree-split: $latest_new
 377         EOF
 378 }
 379
 380 squash_msg()
 381 {
 382         dir="$1"
 383         oldsub="$2"
 384         newsub="$3"
 385         newsub_short=$(git rev-parse --short "$newsub")
 386
 387         if [ -n "$oldsub" ]; then
 388                 oldsub_short=$(git rev-parse --short "$oldsub")
 389                 echo "Squashed '$dir/' changes from $oldsub_short..$newsub_short"
 390                 echo
 391                 git log --pretty=tformat:'%h %s' "$oldsub..$newsub"
 392                 git log --pretty=tformat:'REVERT: %h %s' "$newsub..$oldsub"
 393         else
 394                 echo "Squashed '$dir/' content from commit $newsub_short"
 395         fi
 396
 397         echo
 398         echo "git-subtree-dir: $dir"
 399         echo "git-subtree-split: $newsub"
 400 }
 401
 402 toptree_for_commit()
 403 {
 404         commit="$1"
 405         git log -1 --pretty=format:'%T' "$commit" -- || exit $?
 406 }
 407
 408 subtree_for_commit()
 409 {
 410         commit="$1"
 411         dir="$2"
 412         git ls-tree "$commit" -- "$dir" |
 413         while read mode type tree name; do
 414                 assert [ "$name" = "$dir" ]
 415                 assert [ "$type" = "tree" -o "$type" = "commit" ]
 416                 [ "$type" = "commit" ] && continue  # ignore submodules
 417                 echo $tree
 418                 break
 419         done
 420 }
 421
 422 tree_changed()
 423 {
 424         tree=$1
 425         shift
 426         if [ $# -ne 1 ]; then
 427                 return 0   # weird parents, consider it changed
 428         else
 429                 ptree=$(toptree_for_commit $1)
 430                 if [ "$ptree" != "$tree" ]; then
 431                         return 0   # changed
 432                 else
 433                         return 1   # not changed
 434                 fi
 435         fi
 436 }
 437
 438 new_squash_commit()
 439 {
 440         old="$1"
 441         oldsub="$2"
 442         newsub="$3"
 443         tree=$(toptree_for_commit $newsub) || exit $?
 444         if [ -n "$old" ]; then
 445                 squash_msg "$dir" "$oldsub" "$newsub" |
 446                         git commit-tree "$tree" -p "$old" || exit $?
 447         else
 448                 squash_msg "$dir" "" "$newsub" |
 449                         git commit-tree "$tree" || exit $?
 450         fi
 451 }
 452
 453 copy_or_skip()
 454 {
 455         rev="$1"
 456         tree="$2"
 457         newparents="$3"
 458         assert [ -n "$tree" ]
 459
 460         identical=
 461         nonidentical=
 462         p=
 463         gotparents=
 464         for parent in $newparents; do
 465                 ptree=$(toptree_for_commit $parent) || exit $?
 466                 [ -z "$ptree" ] && continue
 467                 if [ "$ptree" = "$tree" ]; then
 468                         # an identical parent could be used in place of this rev.
 469                         identical="$parent"
 470                 else
 471                         nonidentical="$parent"
 472                 fi
 473
 474                 # sometimes both old parents map to the same newparent;
 475                 # eliminate duplicates
 476                 is_new=1
 477                 for gp in $gotparents; do
 478                         if [ "$gp" = "$parent" ]; then
 479                                 is_new=
 480                                 break
 481                         fi
 482                 done
 483                 if [ -n "$is_new" ]; then
 484                         gotparents="$gotparents $parent"
 485                         p="$p -p $parent"
 486                 fi
 487         done
 488
 489         copycommit=
 490         if [ -n "$identical" ] && [ -n "$nonidentical" ]; then
 491                 extras=$(git rev-list --count $identical..$nonidentical)
 492                 if [ "$extras" -ne 0 ]; then
 493                         # we need to preserve history along the other branch
 494                         copycommit=1
 495                 fi
 496         fi
 497         if [ -n "$identical" ] && [ -z "$copycommit" ]; then
 498                 echo $identical
 499         else
 500                 copy_commit $rev $tree "$p" || exit $?
 501         fi
 502 }
 503
 504 ensure_clean()
 505 {
 506         if ! git diff-index HEAD --exit-code --quiet 2>&1; then
 507                 die "Working tree has modifications.  Cannot add."
 508         fi
 509         if ! git diff-index --cached HEAD --exit-code --quiet 2>&1; then
 510                 die "Index has modifications.  Cannot add."
 511         fi
 512 }
 513
 514 ensure_valid_ref_format()
 515 {
 516         git check-ref-format "refs/heads/$1" ||
 517             die "'$1' does not look like a ref"
 518 }
 519
 520 cmd_add()
 521 {
 522         if [ -e "$dir" ]; then
 523                 die "'$dir' already exists.  Cannot add."
 524         fi
 525
 526         ensure_clean
 527
 528         if [ $# -eq 1 ]; then
 529             git rev-parse -q --verify "$1^{commit}" >/dev/null ||
 530             die "'$1' does not refer to a commit"
 531
 532             "cmd_add_commit" "$@"
 533         elif [ $# -eq 2 ]; then
 534             # Technically we could accept a refspec here but we're
 535             # just going to turn around and add FETCH_HEAD under the
 536             # specified directory.  Allowing a refspec might be
 537             # misleading because we won't do anything with any other
 538             # branches fetched via the refspec.
 539             ensure_valid_ref_format "$2"
 540
 541             "cmd_add_repository" "$@"
 542         else
 543             say "error: parameters were '$@'"
 544             die "Provide either a commit or a repository and commit."
 545         fi
 546 }
 547
 548 cmd_add_repository()
 549 {
 550         echo "git fetch" "$@"
 551         repository=$1
 552         refspec=$2
 553         git fetch "$@" || exit $?
 554         revs=FETCH_HEAD
 555         set -- $revs
 556         cmd_add_commit "$@"
 557 }
 558
 559 cmd_add_commit()
 560 {
 561         revs=$(git rev-parse $default --revs-only "$@") || exit $?
 562         set -- $revs
 563         rev="$1"
 564
 565         debug "Adding $dir as '$rev'..."
 566         git read-tree --prefix="$dir" $rev || exit $?
 567         git checkout -- "$dir" || exit $?
 568         tree=$(git write-tree) || exit $?
 569
 570         headrev=$(git rev-parse HEAD) || exit $?
 571         if [ -n "$headrev" -a "$headrev" != "$rev" ]; then
 572                 headp="-p $headrev"
 573         else
 574                 headp=
 575         fi
 576
 577         if [ -n "$squash" ]; then
 578                 rev=$(new_squash_commit "" "" "$rev") || exit $?
 579                 commit=$(add_squashed_msg "$rev" "$dir" |
 580                          git commit-tree $tree $headp -p "$rev") || exit $?
 581         else
 582                 revp=$(peel_committish "$rev") &&
 583                 commit=$(add_msg "$dir" "$headrev" "$rev" |
 584                          git commit-tree $tree $headp -p "$revp") || exit $?
 585         fi
 586         git reset "$commit" || exit $?
 587
 588         say "Added dir '$dir'"
 589 }
 590
 591 cmd_split()
 592 {
 593         debug "Splitting $dir..."
 594         cache_setup || exit $?
 595
 596         if [ -n "$onto" ]; then
 597                 debug "Reading history for --onto=$onto..."
 598                 git rev-list $onto |
 599                 while read rev; do
 600                         # the 'onto' history is already just the subdir, so
 601                         # any parent we find there can be used verbatim
 602                         debug "  cache: $rev"
 603                         cache_set $rev $rev
 604                 done
 605         fi
 606
 607         if [ -n "$ignore_joins" ]; then
 608                 unrevs=
 609         else
 610                 unrevs="$(find_existing_splits "$dir" "$revs")"
 611         fi
 612
 613         # We can't restrict rev-list to only $dir here, because some of our
 614         # parents have the $dir contents the root, and those won't match.
 615         # (and rev-list --follow doesn't seem to solve this)
 616         grl='git rev-list --topo-order --reverse --parents $revs $unrevs'
 617         revmax=$(eval "$grl" | wc -l)
 618         revcount=0
 619         createcount=0
 620         eval "$grl" |
 621         while read rev parents; do
 622                 revcount=$(($revcount + 1))
 623                 progress "$revcount/$revmax ($createcount)"
 624                 debug "Processing commit: $rev"
 625                 exists=$(cache_get $rev)
 626                 if [ -n "$exists" ]; then
 627                         debug "  prior: $exists"
 628                         continue
 629                 fi
 630                 createcount=$(($createcount + 1))
 631                 debug "  parents: $parents"
 632                 newparents=$(cache_get $parents)
 633                 debug "  newparents: $newparents"
 634
 635                 tree=$(subtree_for_commit $rev "$dir")
 636                 debug "  tree is: $tree"
 637
 638                 check_parents $parents
 639
 640                 # ugly.  is there no better way to tell if this is a subtree
 641                 # vs. a mainline commit?  Does it matter?
 642                 if [ -z $tree ]; then
 643                         set_notree $rev
 644                         if [ -n "$newparents" ]; then
 645                                 cache_set $rev $rev
 646                         fi
 647                         continue
 648                 fi
 649
 650                 newrev=$(copy_or_skip "$rev" "$tree" "$newparents") || exit $?
 651                 debug "  newrev is: $newrev"
 652                 cache_set $rev $newrev
 653                 cache_set latest_new $newrev
 654                 cache_set latest_old $rev
 655         done || exit $?
 656         latest_new=$(cache_get latest_new)
 657         if [ -z "$latest_new" ]; then
 658                 die "No new revisions were found"
 659         fi
 660
 661         if [ -n "$rejoin" ]; then
 662                 debug "Merging split branch into HEAD..."
 663                 latest_old=$(cache_get latest_old)
 664                 git merge -s ours \
 665                         --allow-unrelated-histories \
 666                         -m "$(rejoin_msg "$dir" $latest_old $latest_new)" \
 667                         $latest_new >&2 || exit $?
 668         fi
 669         if [ -n "$branch" ]; then
 670                 if rev_exists "refs/heads/$branch"; then
 671                         if ! rev_is_descendant_of_branch $latest_new $branch; then
 672                                 die "Branch '$branch' is not an ancestor of commit '$latest_new'."
 673                         fi
 674                         action='Updated'
 675                 else
 676                         action='Created'
 677                 fi
 678                 git update-ref -m 'subtree split' "refs/heads/$branch" $latest_new || exit $?
 679                 say "$action branch '$branch'"
 680         fi
 681         echo $latest_new
 682         exit 0
 683 }
 684
 685 cmd_merge()
 686 {
 687         revs=$(git rev-parse $default --revs-only "$@") || exit $?
 688         ensure_clean
 689
 690         set -- $revs
 691         if [ $# -ne 1 ]; then
 692                 die "You must provide exactly one revision.  Got: '$revs'"
 693         fi
 694         rev="$1"
 695
 696         if [ -n "$squash" ]; then
 697                 first_split="$(find_latest_squash "$dir")"
 698                 if [ -z "$first_split" ]; then
 699                         die "Can't squash-merge: '$dir' was never added."
 700                 fi
 701                 set $first_split
 702                 old=$1
 703                 sub=$2
 704                 if [ "$sub" = "$rev" ]; then
 705                         say "Subtree is already at commit $rev."
 706                         exit 0
 707                 fi
 708                 new=$(new_squash_commit "$old" "$sub" "$rev") || exit $?
 709                 debug "New squash commit: $new"
 710                 rev="$new"
 711         fi
 712
 713         version=$(git version)
 714         if [ "$version" \< "git version 1.7" ]; then
 715                 if [ -n "$message" ]; then
 716                         git merge -s subtree --message="$message" $rev
 717                 else
 718                         git merge -s subtree $rev
 719                 fi
 720         else
 721                 if [ -n "$message" ]; then
 722                         git merge -Xsubtree="$prefix" --message="$message" $rev
 723                 else
 724                         git merge -Xsubtree="$prefix" $rev
 725                 fi
 726         fi
 727 }
 728
 729 cmd_pull()
 730 {
 731         if [ $# -ne 2 ]; then
 732             die "You must provide <repository> <ref>"
 733         fi
 734         ensure_clean
 735         ensure_valid_ref_format "$2"
 736         git fetch "$@" || exit $?
 737         revs=FETCH_HEAD
 738         set -- $revs
 739         cmd_merge "$@"
 740 }
 741
 742 cmd_push()
 743 {
 744         if [ $# -ne 2 ]; then
 745             die "You must provide <repository> <ref>"
 746         fi
 747         ensure_valid_ref_format "$2"
 748         if [ -e "$dir" ]; then
 749             repository=$1
 750             refspec=$2
 751             echo "git push using: " $repository $refspec
 752             localrev=$(git subtree split --prefix="$prefix") || die
 753             git push "$repository" $localrev:refs/heads/$refspec
 754         else
 755             die "'$dir' must already exist. Try 'git subtree add'."
 756         fi
 757 }
 758
 759 "cmd_$command" "$@"