git-rebase--interactive.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2006 Johannes E. Schindelin
   4
   5 # SHORT DESCRIPTION
   6 #
   7 # This script makes it easy to fix up commits in the middle of a series,
   8 # and rearrange commits.
   9 #
  10 # The original idea comes from Eric W. Biederman, in
  11 # http://article.gmane.org/gmane.comp.version-control.git/22407
  12 #
  13 # The file containing rebase commands, comments, and empty lines.
  14 # This file is created by "git rebase -i" then edited by the user.  As
  15 # the lines are processed, they are removed from the front of this
  16 # file and written to the tail of $done.
  17 todo="$state_dir"/git-rebase-todo
  18
  19 # The rebase command lines that have already been processed.  A line
  20 # is moved here when it is first handled, before any associated user
  21 # actions.
  22 done="$state_dir"/done
  23
  24 # The commit message that is planned to be used for any changes that
  25 # need to be committed following a user interaction.
  26 msg="$state_dir"/message
  27
  28 # The file into which is accumulated the suggested commit message for
  29 # squash/fixup commands.  When the first of a series of squash/fixups
  30 # is seen, the file is created and the commit message from the
  31 # previous commit and from the first squash/fixup commit are written
  32 # to it.  The commit message for each subsequent squash/fixup commit
  33 # is appended to the file as it is processed.
  34 #
  35 # The first line of the file is of the form
  36 #     # This is a combination of $count commits.
  37 # where $count is the number of commits whose messages have been
  38 # written to the file so far (including the initial "pick" commit).
  39 # Each time that a commit message is processed, this line is read and
  40 # updated.  It is deleted just before the combined commit is made.
  41 squash_msg="$state_dir"/message-squash
  42
  43 # If the current series of squash/fixups has not yet included a squash
  44 # command, then this file exists and holds the commit message of the
  45 # original "pick" commit.  (If the series ends without a "squash"
  46 # command, then this can be used as the commit message of the combined
  47 # commit without opening the editor.)
  48 fixup_msg="$state_dir"/message-fixup
  49
  50 # $rewritten is the name of a directory containing files for each
  51 # commit that is reachable by at least one merge base of $head and
  52 # $upstream. They are not necessarily rewritten, but their children
  53 # might be.  This ensures that commits on merged, but otherwise
  54 # unrelated side branches are left alone. (Think "X" in the man page's
  55 # example.)
  56 rewritten="$state_dir"/rewritten
  57
  58 dropped="$state_dir"/dropped
  59
  60 # A script to set the GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
  61 # GIT_AUTHOR_DATE that will be used for the commit that is currently
  62 # being rebased.
  63 author_script="$state_dir"/author-script
  64
  65 # When an "edit" rebase command is being processed, the SHA1 of the
  66 # commit to be edited is recorded in this file.  When "git rebase
  67 # --continue" is executed, if there are any staged changes then they
  68 # will be amended to the HEAD commit, but only provided the HEAD
  69 # commit is still the commit to be edited.  When any other rebase
  70 # command is processed, this file is deleted.
  71 amend="$state_dir"/amend
  72
  73 # For the post-rewrite hook, we make a list of rewritten commits and
  74 # their new sha1s.  The rewritten-pending list keeps the sha1s of
  75 # commits that have been processed, but not committed yet,
  76 # e.g. because they are waiting for a 'squash' command.
  77 rewritten_list="$state_dir"/rewritten-list
  78 rewritten_pending="$state_dir"/rewritten-pending
  79
  80 GIT_CHERRY_PICK_HELP="$resolvemsg"
  81 export GIT_CHERRY_PICK_HELP
  82
  83 warn () {
  84         printf '%s\n' "$*" >&2
  85 }
  86
  87 # Output the commit message for the specified commit.
  88 commit_message () {
  89         git cat-file commit "$1" | sed "1,/^$/d"
  90 }
  91
  92 orig_reflog_action="$GIT_REFLOG_ACTION"
  93
  94 comment_for_reflog () {
  95         case "$orig_reflog_action" in
  96         ''|rebase*)
  97                 GIT_REFLOG_ACTION="rebase -i ($1)"
  98                 export GIT_REFLOG_ACTION
  99                 ;;
 100         esac
 101 }
 102
 103 last_count=
 104 mark_action_done () {
 105         sed -e 1q < "$todo" >> "$done"
 106         sed -e 1d < "$todo" >> "$todo".new
 107         mv -f "$todo".new "$todo"
 108         new_count=$(sane_grep -c '^[^#]' < "$done")
 109         total=$(($new_count+$(sane_grep -c '^[^#]' < "$todo")))
 110         if test "$last_count" != "$new_count"
 111         then
 112                 last_count=$new_count
 113                 printf "Rebasing (%d/%d)\r" $new_count $total
 114                 test -z "$verbose" || echo
 115         fi
 116 }
 117
 118 make_patch () {
 119         sha1_and_parents="$(git rev-list --parents -1 "$1")"
 120         case "$sha1_and_parents" in
 121         ?*' '?*' '?*)
 122                 git diff --cc $sha1_and_parents
 123                 ;;
 124         ?*' '?*)
 125                 git diff-tree -p "$1^!"
 126                 ;;
 127         *)
 128                 echo "Root commit"
 129                 ;;
 130         esac > "$state_dir"/patch
 131         test -f "$msg" ||
 132                 commit_message "$1" > "$msg"
 133         test -f "$author_script" ||
 134                 get_author_ident_from_commit "$1" > "$author_script"
 135 }
 136
 137 die_with_patch () {
 138         echo "$1" > "$state_dir"/stopped-sha
 139         make_patch "$1"
 140         git rerere
 141         die "$2"
 142 }
 143
 144 exit_with_patch () {
 145         echo "$1" > "$state_dir"/stopped-sha
 146         make_patch $1
 147         git rev-parse --verify HEAD > "$amend"
 148         warn "You can amend the commit now, with"
 149         warn
 150         warn "  git commit --amend"
 151         warn
 152         warn "Once you are satisfied with your changes, run"
 153         warn
 154         warn "  git rebase --continue"
 155         warn
 156         exit $2
 157 }
 158
 159 die_abort () {
 160         rm -rf "$state_dir"
 161         die "$1"
 162 }
 163
 164 has_action () {
 165         sane_grep '^[^#]' "$1" >/dev/null
 166 }
 167
 168 is_empty_commit() {
 169         tree=$(git rev-parse -q --verify "$1"^{tree} 2>/dev/null ||
 170                 die "$1: not a commit that can be picked")
 171         ptree=$(git rev-parse -q --verify "$1"^^{tree} 2>/dev/null ||
 172                 ptree=4b825dc642cb6eb9a060e54bf8d69288fbee4904)
 173         test "$tree" = "$ptree"
 174 }
 175
 176 # Run command with GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
 177 # GIT_AUTHOR_DATE exported from the current environment.
 178 do_with_author () {
 179         (
 180                 export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
 181                 "$@"
 182         )
 183 }
 184
 185 git_sequence_editor () {
 186         if test -z "$GIT_SEQUENCE_EDITOR"
 187         then
 188                 GIT_SEQUENCE_EDITOR="$(git config sequence.editor)"
 189                 if [ -z "$GIT_SEQUENCE_EDITOR" ]
 190                 then
 191                         GIT_SEQUENCE_EDITOR="$(git var GIT_EDITOR)" || return $?
 192                 fi
 193         fi
 194
 195         eval "$GIT_SEQUENCE_EDITOR" '"$@"'
 196 }
 197
 198 pick_one () {
 199         ff=--ff
 200
 201         case "$1" in -n) sha1=$2; ff= ;; *) sha1=$1 ;; esac
 202         case "$force_rebase" in '') ;; ?*) ff= ;; esac
 203         output git rev-parse --verify $sha1 || die "Invalid commit name: $sha1"
 204
 205         if is_empty_commit "$sha1"
 206         then
 207                 empty_args="--allow-empty"
 208         fi
 209
 210         test -d "$rewritten" &&
 211                 pick_one_preserving_merges "$@" && return
 212         output git cherry-pick $empty_args $ff "$@"
 213 }
 214
 215 pick_one_preserving_merges () {
 216         fast_forward=t
 217         case "$1" in
 218         -n)
 219                 fast_forward=f
 220                 sha1=$2
 221                 ;;
 222         *)
 223                 sha1=$1
 224                 ;;
 225         esac
 226         sha1=$(git rev-parse $sha1)
 227
 228         if test -f "$state_dir"/current-commit
 229         then
 230                 if test "$fast_forward" = t
 231                 then
 232                         while read current_commit
 233                         do
 234                                 git rev-parse HEAD > "$rewritten"/$current_commit
 235                         done <"$state_dir"/current-commit
 236                         rm "$state_dir"/current-commit ||
 237                         die "Cannot write current commit's replacement sha1"
 238                 fi
 239         fi
 240
 241         echo $sha1 >> "$state_dir"/current-commit
 242
 243         # rewrite parents; if none were rewritten, we can fast-forward.
 244         new_parents=
 245         pend=" $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)"
 246         if test "$pend" = " "
 247         then
 248                 pend=" root"
 249         fi
 250         while [ "$pend" != "" ]
 251         do
 252                 p=$(expr "$pend" : ' \([^ ]*\)')
 253                 pend="${pend# $p}"
 254
 255                 if test -f "$rewritten"/$p
 256                 then
 257                         new_p=$(cat "$rewritten"/$p)
 258
 259                         # If the todo reordered commits, and our parent is marked for
 260                         # rewriting, but hasn't been gotten to yet, assume the user meant to
 261                         # drop it on top of the current HEAD
 262                         if test -z "$new_p"
 263                         then
 264                                 new_p=$(git rev-parse HEAD)
 265                         fi
 266
 267                         test $p != $new_p && fast_forward=f
 268                         case "$new_parents" in
 269                         *$new_p*)
 270                                 ;; # do nothing; that parent is already there
 271                         *)
 272                                 new_parents="$new_parents $new_p"
 273                                 ;;
 274                         esac
 275                 else
 276                         if test -f "$dropped"/$p
 277                         then
 278                                 fast_forward=f
 279                                 replacement="$(cat "$dropped"/$p)"
 280                                 test -z "$replacement" && replacement=root
 281                                 pend=" $replacement$pend"
 282                         else
 283                                 new_parents="$new_parents $p"
 284                         fi
 285                 fi
 286         done
 287         case $fast_forward in
 288         t)
 289                 output warn "Fast-forward to $sha1"
 290                 output git reset --hard $sha1 ||
 291                         die "Cannot fast-forward to $sha1"
 292                 ;;
 293         f)
 294                 first_parent=$(expr "$new_parents" : ' \([^ ]*\)')
 295
 296                 if [ "$1" != "-n" ]
 297                 then
 298                         # detach HEAD to current parent
 299                         output git checkout $first_parent 2> /dev/null ||
 300                                 die "Cannot move HEAD to $first_parent"
 301                 fi
 302
 303                 case "$new_parents" in
 304                 ' '*' '*)
 305                         test "a$1" = a-n && die "Refusing to squash a merge: $sha1"
 306
 307                         # redo merge
 308                         author_script_content=$(get_author_ident_from_commit $sha1)
 309                         eval "$author_script_content"
 310                         msg_content="$(commit_message $sha1)"
 311                         # No point in merging the first parent, that's HEAD
 312                         new_parents=${new_parents# $first_parent}
 313                         if ! do_with_author output \
 314                                 git merge --no-ff ${strategy:+-s $strategy} -m \
 315                                         "$msg_content" $new_parents
 316                         then
 317                                 printf "%s\n" "$msg_content" > "$GIT_DIR"/MERGE_MSG
 318                                 die_with_patch $sha1 "Error redoing merge $sha1"
 319                         fi
 320                         echo "$sha1 $(git rev-parse HEAD^0)" >> "$rewritten_list"
 321                         ;;
 322                 *)
 323                         output git cherry-pick "$@" ||
 324                                 die_with_patch $sha1 "Could not pick $sha1"
 325                         ;;
 326                 esac
 327                 ;;
 328         esac
 329 }
 330
 331 nth_string () {
 332         case "$1" in
 333         *1[0-9]|*[04-9]) echo "$1"th;;
 334         *1) echo "$1"st;;
 335         *2) echo "$1"nd;;
 336         *3) echo "$1"rd;;
 337         esac
 338 }
 339
 340 update_squash_messages () {
 341         if test -f "$squash_msg"; then
 342                 mv "$squash_msg" "$squash_msg".bak || exit
 343                 count=$(($(sed -n \
 344                         -e "1s/^# This is a combination of \(.*\) commits\./\1/p" \
 345                         -e "q" < "$squash_msg".bak)+1))
 346                 {
 347                         echo "# This is a combination of $count commits."
 348                         sed -e 1d -e '2,/^./{
 349                                 /^$/d
 350                         }' <"$squash_msg".bak
 351                 } >"$squash_msg"
 352         else
 353                 commit_message HEAD > "$fixup_msg" || die "Cannot write $fixup_msg"
 354                 count=2
 355                 {
 356                         echo "# This is a combination of 2 commits."
 357                         echo "# The first commit's message is:"
 358                         echo
 359                         cat "$fixup_msg"
 360                 } >"$squash_msg"
 361         fi
 362         case $1 in
 363         squash)
 364                 rm -f "$fixup_msg"
 365                 echo
 366                 echo "# This is the $(nth_string $count) commit message:"
 367                 echo
 368                 commit_message $2
 369                 ;;
 370         fixup)
 371                 echo
 372                 echo "# The $(nth_string $count) commit message will be skipped:"
 373                 echo
 374                 commit_message $2 | sed -e 's/^/#       /'
 375                 ;;
 376         esac >>"$squash_msg"
 377 }
 378
 379 peek_next_command () {
 380         sed -n -e "/^#/d" -e '/^$/d' -e "s/ .*//p" -e "q" < "$todo"
 381 }
 382
 383 # A squash/fixup has failed.  Prepare the long version of the squash
 384 # commit message, then die_with_patch.  This code path requires the
 385 # user to edit the combined commit message for all commits that have
 386 # been squashed/fixedup so far.  So also erase the old squash
 387 # messages, effectively causing the combined commit to be used as the
 388 # new basis for any further squash/fixups.  Args: sha1 rest
 389 die_failed_squash() {
 390         mv "$squash_msg" "$msg" || exit
 391         rm -f "$fixup_msg"
 392         cp "$msg" "$GIT_DIR"/MERGE_MSG || exit
 393         warn
 394         warn "Could not apply $1... $2"
 395         die_with_patch $1 ""
 396 }
 397
 398 flush_rewritten_pending() {
 399         test -s "$rewritten_pending" || return
 400         newsha1="$(git rev-parse HEAD^0)"
 401         sed "s/$/ $newsha1/" < "$rewritten_pending" >> "$rewritten_list"
 402         rm -f "$rewritten_pending"
 403 }
 404
 405 record_in_rewritten() {
 406         oldsha1="$(git rev-parse $1)"
 407         echo "$oldsha1" >> "$rewritten_pending"
 408
 409         case "$(peek_next_command)" in
 410         squash|s|fixup|f)
 411                 ;;
 412         *)
 413                 flush_rewritten_pending
 414                 ;;
 415         esac
 416 }
 417
 418 do_pick () {
 419         if test "$(git rev-parse HEAD)" = "$squash_onto"
 420         then
 421                 # Set the correct commit message and author info on the
 422                 # sentinel root before cherry-picking the original changes
 423                 # without committing (-n).  Finally, update the sentinel again
 424                 # to include these changes.  If the cherry-pick results in a
 425                 # conflict, this means our behaviour is similar to a standard
 426                 # failed cherry-pick during rebase, with a dirty index to
 427                 # resolve before manually running git commit --amend then git
 428                 # rebase --continue.
 429                 git commit --allow-empty --allow-empty-message --amend \
 430                            --no-post-rewrite -n -q -C $1 &&
 431                         pick_one -n $1 &&
 432                         git commit --allow-empty --allow-empty-message \
 433                                    --amend --no-post-rewrite -n -q -C $1 ||
 434                         die_with_patch $1 "Could not apply $1... $2"
 435         else
 436                 pick_one $1 ||
 437                         die_with_patch $1 "Could not apply $1... $2"
 438         fi
 439 }
 440
 441 do_next () {
 442         rm -f "$msg" "$author_script" "$amend" || exit
 443         read -r command sha1 rest < "$todo"
 444         case "$command" in
 445         '#'*|''|noop)
 446                 mark_action_done
 447                 ;;
 448         pick|p)
 449                 comment_for_reflog pick
 450
 451                 mark_action_done
 452                 do_pick $sha1 "$rest"
 453                 record_in_rewritten $sha1
 454                 ;;
 455         reword|r)
 456                 comment_for_reflog reword
 457
 458                 mark_action_done
 459                 do_pick $sha1 "$rest"
 460                 git commit --amend --no-post-rewrite || {
 461                         warn "Could not amend commit after successfully picking $sha1... $rest"
 462                         warn "This is most likely due to an empty commit message, or the pre-commit hook"
 463                         warn "failed. If the pre-commit hook failed, you may need to resolve the issue before"
 464                         warn "you are able to reword the commit."
 465                         exit_with_patch $sha1 1
 466                 }
 467                 record_in_rewritten $sha1
 468                 ;;
 469         edit|e)
 470                 comment_for_reflog edit
 471
 472                 mark_action_done
 473                 do_pick $sha1 "$rest"
 474                 warn "Stopped at $sha1... $rest"
 475                 exit_with_patch $sha1 0
 476                 ;;
 477         squash|s|fixup|f)
 478                 case "$command" in
 479                 squash|s)
 480                         squash_style=squash
 481                         ;;
 482                 fixup|f)
 483                         squash_style=fixup
 484                         ;;
 485                 esac
 486                 comment_for_reflog $squash_style
 487
 488                 test -f "$done" && has_action "$done" ||
 489                         die "Cannot '$squash_style' without a previous commit"
 490
 491                 mark_action_done
 492                 update_squash_messages $squash_style $sha1
 493                 author_script_content=$(get_author_ident_from_commit HEAD)
 494                 echo "$author_script_content" > "$author_script"
 495                 eval "$author_script_content"
 496                 if ! pick_one -n $sha1
 497                 then
 498                         git rev-parse --verify HEAD >"$amend"
 499                         die_failed_squash $sha1 "$rest"
 500                 fi
 501                 case "$(peek_next_command)" in
 502                 squash|s|fixup|f)
 503                         # This is an intermediate commit; its message will only be
 504                         # used in case of trouble.  So use the long version:
 505                         do_with_author output git commit --amend --no-verify -F "$squash_msg" ||
 506                                 die_failed_squash $sha1 "$rest"
 507                         ;;
 508                 *)
 509                         # This is the final command of this squash/fixup group
 510                         if test -f "$fixup_msg"
 511                         then
 512                                 do_with_author git commit --amend --no-verify -F "$fixup_msg" ||
 513                                         die_failed_squash $sha1 "$rest"
 514                         else
 515                                 cp "$squash_msg" "$GIT_DIR"/SQUASH_MSG || exit
 516                                 rm -f "$GIT_DIR"/MERGE_MSG
 517                                 do_with_author git commit --amend --no-verify -F "$GIT_DIR"/SQUASH_MSG -e ||
 518                                         die_failed_squash $sha1 "$rest"
 519                         fi
 520                         rm -f "$squash_msg" "$fixup_msg"
 521                         ;;
 522                 esac
 523                 record_in_rewritten $sha1
 524                 ;;
 525         x|"exec")
 526                 read -r command rest < "$todo"
 527                 mark_action_done
 528                 printf 'Executing: %s\n' "$rest"
 529                 # "exec" command doesn't take a sha1 in the todo-list.
 530                 # => can't just use $sha1 here.
 531                 git rev-parse --verify HEAD > "$state_dir"/stopped-sha
 532                 ${SHELL:-@SHELL_PATH@} -c "$rest" # Actual execution
 533                 status=$?
 534                 # Run in subshell because require_clean_work_tree can die.
 535                 dirty=f
 536                 (require_clean_work_tree "rebase" 2>/dev/null) || dirty=t
 537                 if test "$status" -ne 0
 538                 then
 539                         warn "Execution failed: $rest"
 540                         test "$dirty" = f ||
 541                         warn "and made changes to the index and/or the working tree"
 542
 543                         warn "You can fix the problem, and then run"
 544                         warn
 545                         warn "  git rebase --continue"
 546                         warn
 547                         if test $status -eq 127         # command not found
 548                         then
 549                                 status=1
 550                         fi
 551                         exit "$status"
 552                 elif test "$dirty" = t
 553                 then
 554                         warn "Execution succeeded: $rest"
 555                         warn "but left changes to the index and/or the working tree"
 556                         warn "Commit or stash your changes, and then run"
 557                         warn
 558                         warn "  git rebase --continue"
 559                         warn
 560                         exit 1
 561                 fi
 562                 ;;
 563         *)
 564                 warn "Unknown command: $command $sha1 $rest"
 565                 if git rev-parse --verify -q "$sha1" >/dev/null
 566                 then
 567                         die_with_patch $sha1 "Please fix this in the file $todo."
 568                 else
 569                         die "Please fix this in the file $todo."
 570                 fi
 571                 ;;
 572         esac
 573         test -s "$todo" && return
 574
 575         comment_for_reflog finish &&
 576         newhead=$(git rev-parse HEAD) &&
 577         case $head_name in
 578         refs/*)
 579                 message="$GIT_REFLOG_ACTION: $head_name onto $onto" &&
 580                 git update-ref -m "$message" $head_name $newhead $orig_head &&
 581                 git symbolic-ref \
 582                   -m "$GIT_REFLOG_ACTION: returning to $head_name" \
 583                   HEAD $head_name
 584                 ;;
 585         esac && {
 586                 test ! -f "$state_dir"/verbose ||
 587                         git diff-tree --stat $orig_head..HEAD
 588         } &&
 589         {
 590                 test -s "$rewritten_list" &&
 591                 git notes copy --for-rewrite=rebase < "$rewritten_list" ||
 592                 true # we don't care if this copying failed
 593         } &&
 594         if test -x "$GIT_DIR"/hooks/post-rewrite &&
 595                 test -s "$rewritten_list"; then
 596                 "$GIT_DIR"/hooks/post-rewrite rebase < "$rewritten_list"
 597                 true # we don't care if this hook failed
 598         fi &&
 599         rm -rf "$state_dir" &&
 600         git gc --auto &&
 601         warn "Successfully rebased and updated $head_name."
 602
 603         exit
 604 }
 605
 606 do_rest () {
 607         while :
 608         do
 609                 do_next
 610         done
 611 }
 612
 613 # skip picking commits whose parents are unchanged
 614 skip_unnecessary_picks () {
 615         fd=3
 616         while read -r command rest
 617         do
 618                 # fd=3 means we skip the command
 619                 case "$fd,$command" in
 620                 3,pick|3,p)
 621                         # pick a commit whose parent is current $onto -> skip
 622                         sha1=${rest%% *}
 623                         case "$(git rev-parse --verify --quiet "$sha1"^)" in
 624                         "$onto"*)
 625                                 onto=$sha1
 626                                 ;;
 627                         *)
 628                                 fd=1
 629                                 ;;
 630                         esac
 631                         ;;
 632                 3,#*|3,)
 633                         # copy comments
 634                         ;;
 635                 *)
 636                         fd=1
 637                         ;;
 638                 esac
 639                 printf '%s\n' "$command${rest:+ }$rest" >&$fd
 640         done <"$todo" >"$todo.new" 3>>"$done" &&
 641         mv -f "$todo".new "$todo" &&
 642         case "$(peek_next_command)" in
 643         squash|s|fixup|f)
 644                 record_in_rewritten "$onto"
 645                 ;;
 646         esac ||
 647         die "Could not skip unnecessary pick commands"
 648 }
 649
 650 # Rearrange the todo list that has both "pick sha1 msg" and
 651 # "pick sha1 fixup!/squash! msg" appears in it so that the latter
 652 # comes immediately after the former, and change "pick" to
 653 # "fixup"/"squash".
 654 rearrange_squash () {
 655         # extract fixup!/squash! lines and resolve any referenced sha1's
 656         while read -r pick sha1 message
 657         do
 658                 case "$message" in
 659                 "squash! "*|"fixup! "*)
 660                         action="${message%%!*}"
 661                         rest="${message#*! }"
 662                         echo "$sha1 $action $rest"
 663                         # if it's a single word, try to resolve to a full sha1 and
 664                         # emit a second copy. This allows us to match on both message
 665                         # and on sha1 prefix
 666                         if test "${rest#* }" = "$rest"; then
 667                                 fullsha="$(git rev-parse -q --verify "$rest" 2>/dev/null)"
 668                                 if test -n "$fullsha"; then
 669                                         # prefix the action to uniquely identify this line as
 670                                         # intended for full sha1 match
 671                                         echo "$sha1 +$action $fullsha"
 672                                 fi
 673                         fi
 674                 esac
 675         done >"$1.sq" <"$1"
 676         test -s "$1.sq" || return
 677
 678         used=
 679         while read -r pick sha1 message
 680         do
 681                 case " $used" in
 682                 *" $sha1 "*) continue ;;
 683                 esac
 684                 printf '%s\n' "$pick $sha1 $message"
 685                 used="$used$sha1 "
 686                 while read -r squash action msg_content
 687                 do
 688                         case " $used" in
 689                         *" $squash "*) continue ;;
 690                         esac
 691                         emit=0
 692                         case "$action" in
 693                         +*)
 694                                 action="${action#+}"
 695                                 # full sha1 prefix test
 696                                 case "$msg_content" in "$sha1"*) emit=1;; esac ;;
 697                         *)
 698                                 # message prefix test
 699                                 case "$message" in "$msg_content"*) emit=1;; esac ;;
 700                         esac
 701                         if test $emit = 1; then
 702                                 printf '%s\n' "$action $squash $action! $msg_content"
 703                                 used="$used$squash "
 704                         fi
 705                 done <"$1.sq"
 706         done >"$1.rearranged" <"$1"
 707         cat "$1.rearranged" >"$1"
 708         rm -f "$1.sq" "$1.rearranged"
 709 }
 710
 711 # Add commands after a pick or after a squash/fixup serie
 712 # in the todo list.
 713 add_exec_commands () {
 714         {
 715                 first=t
 716                 while read -r insn rest
 717                 do
 718                         case $insn in
 719                         pick)
 720                                 test -n "$first" ||
 721                                 printf "%s" "$cmd"
 722                                 ;;
 723                         esac
 724                         printf "%s %s\n" "$insn" "$rest"
 725                         first=
 726                 done
 727                 printf "%s" "$cmd"
 728         } <"$1" >"$1.new" &&
 729         mv "$1.new" "$1"
 730 }
 731
 732 case "$action" in
 733 continue)
 734         # do we have anything to commit?
 735         if git diff-index --cached --quiet HEAD --
 736         then
 737                 : Nothing to commit -- skip this
 738         else
 739                 if ! test -f "$author_script"
 740                 then
 741                         die "You have staged changes in your working tree. If these changes are meant to be
 742 squashed into the previous commit, run:
 743
 744   git commit --amend
 745
 746 If they are meant to go into a new commit, run:
 747
 748   git commit
 749
 750 In both case, once you're done, continue with:
 751
 752   git rebase --continue
 753 "
 754                 fi
 755                 . "$author_script" ||
 756                         die "Error trying to find the author identity to amend commit"
 757                 if test -f "$amend"
 758                 then
 759                         current_head=$(git rev-parse --verify HEAD)
 760                         test "$current_head" = $(cat "$amend") ||
 761                         die "\
 762 You have uncommitted changes in your working tree. Please, commit them
 763 first and then run 'git rebase --continue' again."
 764                         do_with_author git commit --amend --no-verify -F "$msg" -e ||
 765                                 die "Could not commit staged changes."
 766                 else
 767                         do_with_author git commit --no-verify -F "$msg" -e ||
 768                                 die "Could not commit staged changes."
 769                 fi
 770         fi
 771
 772         record_in_rewritten "$(cat "$state_dir"/stopped-sha)"
 773
 774         require_clean_work_tree "rebase"
 775         do_rest
 776         ;;
 777 skip)
 778         git rerere clear
 779
 780         do_rest
 781         ;;
 782 esac
 783
 784 git var GIT_COMMITTER_IDENT >/dev/null ||
 785         die "You need to set your committer info first"
 786
 787 comment_for_reflog start
 788
 789 if test ! -z "$switch_to"
 790 then
 791         output git checkout "$switch_to" -- ||
 792                 die "Could not checkout $switch_to"
 793 fi
 794
 795 orig_head=$(git rev-parse --verify HEAD) || die "No HEAD?"
 796 mkdir "$state_dir" || die "Could not create temporary $state_dir"
 797
 798 : > "$state_dir"/interactive || die "Could not mark as interactive"
 799 write_basic_state
 800 if test t = "$preserve_merges"
 801 then
 802         if test -z "$rebase_root"
 803         then
 804                 mkdir "$rewritten" &&
 805                 for c in $(git merge-base --all $orig_head $upstream)
 806                 do
 807                         echo $onto > "$rewritten"/$c ||
 808                                 die "Could not init rewritten commits"
 809                 done
 810         else
 811                 mkdir "$rewritten" &&
 812                 echo $onto > "$rewritten"/root ||
 813                         die "Could not init rewritten commits"
 814         fi
 815         # No cherry-pick because our first pass is to determine
 816         # parents to rewrite and skipping dropped commits would
 817         # prematurely end our probe
 818         merges_option=
 819 else
 820         merges_option="--no-merges --cherry-pick"
 821 fi
 822
 823 shorthead=$(git rev-parse --short $orig_head)
 824 shortonto=$(git rev-parse --short $onto)
 825 if test -z "$rebase_root"
 826         # this is now equivalent to ! -z "$upstream"
 827 then
 828         shortupstream=$(git rev-parse --short $upstream)
 829         revisions=$upstream...$orig_head
 830         shortrevisions=$shortupstream..$shorthead
 831 else
 832         revisions=$onto...$orig_head
 833         shortrevisions=$shorthead
 834 fi
 835 git rev-list $merges_option --pretty=oneline --abbrev-commit \
 836         --abbrev=7 --reverse --left-right --topo-order \
 837         $revisions | \
 838         sed -n "s/^>//p" |
 839 while read -r shortsha1 rest
 840 do
 841
 842         if test -z "$keep_empty" && is_empty_commit $shortsha1
 843         then
 844                 comment_out="# "
 845         else
 846                 comment_out=
 847         fi
 848
 849         if test t != "$preserve_merges"
 850         then
 851                 printf '%s\n' "${comment_out}pick $shortsha1 $rest" >>"$todo"
 852         else
 853                 sha1=$(git rev-parse $shortsha1)
 854                 if test -z "$rebase_root"
 855                 then
 856                         preserve=t
 857                         for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -s -f2-)
 858                         do
 859                                 if test -f "$rewritten"/$p
 860                                 then
 861                                         preserve=f
 862                                 fi
 863                         done
 864                 else
 865                         preserve=f
 866                 fi
 867                 if test f = "$preserve"
 868                 then
 869                         touch "$rewritten"/$sha1
 870                         printf '%s\n' "${comment_out}pick $shortsha1 $rest" >>"$todo"
 871                 fi
 872         fi
 873 done
 874
 875 # Watch for commits that been dropped by --cherry-pick
 876 if test t = "$preserve_merges"
 877 then
 878         mkdir "$dropped"
 879         # Save all non-cherry-picked changes
 880         git rev-list $revisions --left-right --cherry-pick | \
 881                 sed -n "s/^>//p" > "$state_dir"/not-cherry-picks
 882         # Now all commits and note which ones are missing in
 883         # not-cherry-picks and hence being dropped
 884         git rev-list $revisions |
 885         while read rev
 886         do
 887                 if test -f "$rewritten"/$rev -a "$(sane_grep "$rev" "$state_dir"/not-cherry-picks)" = ""
 888                 then
 889                         # Use -f2 because if rev-list is telling us this commit is
 890                         # not worthwhile, we don't want to track its multiple heads,
 891                         # just the history of its first-parent for others that will
 892                         # be rebasing on top of it
 893                         git rev-list --parents -1 $rev | cut -d' ' -s -f2 > "$dropped"/$rev
 894                         short=$(git rev-list -1 --abbrev-commit --abbrev=7 $rev)
 895                         sane_grep -v "^[a-z][a-z]* $short" <"$todo" > "${todo}2" ; mv "${todo}2" "$todo"
 896                         rm "$rewritten"/$rev
 897                 fi
 898         done
 899 fi
 900
 901 test -s "$todo" || echo noop >> "$todo"
 902 test -n "$autosquash" && rearrange_squash "$todo"
 903 test -n "$cmd" && add_exec_commands "$todo"
 904
 905 cat >> "$todo" << EOF
 906
 907 # Rebase $shortrevisions onto $shortonto
 908 #
 909 # Commands:
 910 #  p, pick = use commit
 911 #  r, reword = use commit, but edit the commit message
 912 #  e, edit = use commit, but stop for amending
 913 #  s, squash = use commit, but meld into previous commit
 914 #  f, fixup = like "squash", but discard this commit's log message
 915 #  x, exec = run command (the rest of the line) using shell
 916 #
 917 # These lines can be re-ordered; they are executed from top to bottom.
 918 #
 919 # If you remove a line here THAT COMMIT WILL BE LOST.
 920 # However, if you remove everything, the rebase will be aborted.
 921 #
 922 EOF
 923
 924 if test -z "$keep_empty"
 925 then
 926         echo "# Note that empty commits are commented out" >>"$todo"
 927 fi
 928
 929
 930 has_action "$todo" ||
 931         die_abort "Nothing to do"
 932
 933 cp "$todo" "$todo".backup
 934 git_sequence_editor "$todo" ||
 935         die_abort "Could not execute editor"
 936
 937 has_action "$todo" ||
 938         die_abort "Nothing to do"
 939
 940 test -d "$rewritten" || test -n "$force_rebase" || skip_unnecessary_picks
 941
 942 output git checkout $onto || die_abort "could not detach HEAD"
 943 git update-ref ORIG_HEAD $orig_head
 944 do_rest