#!/bin/sh
#
# Copyright (c) 2005 Junio C Hamano.
#

SUBDIRECTORY_OK=Yes
OPTIONS_KEEPDASHDASH=
OPTIONS_STUCKLONG=t
OPTIONS_SPEC="\
git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] [<upstream>] [<branch>]
git rebase [-i] [options] [--exec <cmd>] [--onto <newbase>] --root [<branch>]
git rebase --continue | --abort | --skip | --edit-todo
--
 Available options are
v,verbose!         display a diffstat of what changed upstream
q,quiet!           be quiet. implies --no-stat
autostash          automatically stash/stash pop before and after
fork-point         use 'merge-base --fork-point' to refine upstream
onto=!             rebase onto given branch instead of upstream
p,preserve-merges! try to recreate merges instead of ignoring them
s,strategy=!       use the given merge strategy
no-ff!             cherry-pick all commits, even if unchanged
m,merge!           use merging strategies to rebase
i,interactive!     let the user edit the list of commits to rebase
x,exec=!           add exec lines after each commit of the editable list
k,keep-empty       preserve empty commits during rebase
f,force-rebase!    force rebase even if branch is up to date
X,strategy-option=! pass the argument through to the merge strategy
stat!              display a diffstat of what changed upstream
n,no-stat!         do not show diffstat of what changed upstream
verify             allow pre-rebase hook to run
rerere-autoupdate  allow rerere to update index with resolved conflicts
root!              rebase all reachable commits up to the root(s)
autosquash         move commits that begin with squash!/fixup! under -i
committer-date-is-author-date! passed to 'git am'
ignore-date!       passed to 'git am'
signoff            passed to 'git am'
whitespace=!       passed to 'git apply'
ignore-whitespace! passed to 'git apply'
C=!                passed to 'git apply'
S,gpg-sign?        GPG-sign commits
 Actions:
continue!          continue
abort!             abort and check out the original branch
skip!              skip current patch and continue
edit-todo!         edit the todo list during an interactive rebase
quit!              abort but keep HEAD where it is
"
. git-sh-setup
set_reflog_action rebase
require_work_tree_exists
cd_to_toplevel

LF='
'
ok_to_skip_pre_rebase=
resolvemsg="
$(gettext 'Resolve all conflicts manually, mark them as resolved with
"git add/rm <conflicted_files>", then run "git rebase --continue".
You can instead skip this commit: run "git rebase --skip".
To abort and get back to the state before "git rebase", run "git rebase --abort".')
"
squash_onto=
unset onto
unset restrict_revision
cmd=
strategy=
strategy_opts=
do_merge=
merge_dir="$GIT_DIR"/rebase-merge
apply_dir="$GIT_DIR"/rebase-apply
verbose=
diffstat=
test "$(git config --bool rebase.stat)" = true && diffstat=t
autostash="$(git config --bool rebase.autostash || echo false)"
fork_point=auto
git_am_opt=
git_format_patch_opt=
rebase_root=
force_rebase=
allow_rerere_autoupdate=
# Non-empty if a rebase was in progress when 'git rebase' was invoked
in_progress=
# One of {am, merge, interactive}
type=
# One of {"$GIT_DIR"/rebase-apply, "$GIT_DIR"/rebase-merge}
state_dir=
# One of {'', continue, skip, abort}, as parsed from command line
action=
preserve_merges=
autosquash=
keep_empty=
test "$(git config --bool rebase.autosquash)" = "true" && autosquash=t
case "$(git config --bool commit.gpgsign)" in
true)   gpg_sign_opt=-S ;;
*)      gpg_sign_opt= ;;
esac

read_basic_state () {
        test -f "$state_dir/head-name" &&
        test -f "$state_dir/onto" &&
        head_name=$(cat "$state_dir"/head-name) &&
        onto=$(cat "$state_dir"/onto) &&
        # We always write to orig-head, but interactive rebase used to write to
        # head. Fall back to reading from head to cover for the case that the
        # user upgraded git with an ongoing interactive rebase.
        if test -f "$state_dir"/orig-head
        then
                orig_head=$(cat "$state_dir"/orig-head)
        else
                orig_head=$(cat "$state_dir"/head)
        fi &&
        GIT_QUIET=$(cat "$state_dir"/quiet) &&
        test -f "$state_dir"/verbose && verbose=t
        test -f "$state_dir"/strategy && strategy="$(cat "$state_dir"/strategy)"
        test -f "$state_dir"/strategy_opts &&
                strategy_opts="$(cat "$state_dir"/strategy_opts)"
        test -f "$state_dir"/allow_rerere_autoupdate &&
                allow_rerere_autoupdate="$(cat "$state_dir"/allow_rerere_autoupdate)"
        test -f "$state_dir"/gpg_sign_opt &&
                gpg_sign_opt="$(cat "$state_dir"/gpg_sign_opt)"
}

write_basic_state () {
        echo "$head_name" > "$state_dir"/head-name &&
        echo "$onto" > "$state_dir"/onto &&
        echo "$orig_head" > "$state_dir"/orig-head &&
        echo "$GIT_QUIET" > "$state_dir"/quiet &&
        test t = "$verbose" && : > "$state_dir"/verbose
        test -n "$strategy" && echo "$strategy" > "$state_dir"/strategy
        test -n "$strategy_opts" && echo "$strategy_opts" > \
                "$state_dir"/strategy_opts
        test -n "$allow_rerere_autoupdate" && echo "$allow_rerere_autoupdate" > \
                "$state_dir"/allow_rerere_autoupdate
        test -n "$gpg_sign_opt" && echo "$gpg_sign_opt" > "$state_dir"/gpg_sign_opt
}

output () {
        case "$verbose" in
        '')
                output=$("$@" 2>&1 )
                status=$?
                test $status != 0 && printf "%s\n" "$output"
                return $status
                ;;
        *)
                "$@"
                ;;
        esac
}

move_to_original_branch () {
        case "$head_name" in
        refs/*)
                message="rebase finished: $head_name onto $onto"
                git update-ref -m "$message" \
                        $head_name $(git rev-parse HEAD) $orig_head &&
                git symbolic-ref \
                        -m "rebase finished: returning to $head_name" \
                        HEAD $head_name ||
                die "$(eval_gettext "Could not move back to \$head_name")"
                ;;
        esac
}

apply_autostash () {
        if test -f "$state_dir/autostash"
        then
                stash_sha1=$(cat "$state_dir/autostash")
                if git stash apply $stash_sha1 >/dev/null 2>&1
                then
                        echo "$(gettext 'Applied autostash.')" >&2
                else
                        git stash store -m "autostash" -q $stash_sha1 ||
                        die "$(eval_gettext "Cannot store \$stash_sha1")"
                        gettext 'Applying autostash resulted in conflicts.
Your changes are safe in the stash.
You can run "git stash pop" or "git stash drop" at any time.
' >&2
                fi
        fi
}

finish_rebase () {
        apply_autostash &&
        { git gc --auto || true; } &&
        rm -rf "$state_dir"
}

run_specific_rebase () {
        if [ "$interactive_rebase" = implied ]; then
                GIT_EDITOR=:
                export GIT_EDITOR
                autosquash=
        fi
        . git-rebase--$type
        ret=$?
        if test $ret -eq 0
        then
                finish_rebase
        elif test $ret -eq 2 # special exit status for rebase -i
        then
                apply_autostash &&
                rm -rf "$state_dir" &&
                die "Nothing to do"
        fi
        exit $ret
}

run_pre_rebase_hook () {
        if test -z "$ok_to_skip_pre_rebase" &&
           test -x "$(git rev-parse --git-path hooks/pre-rebase)"
        then
                "$(git rev-parse --git-path hooks/pre-rebase)" ${1+"$@"} ||
                die "$(gettext "The pre-rebase hook refused to rebase.")"
        fi
}

test -f "$apply_dir"/applying &&
        die "$(gettext "It looks like 'git am' is in progress. Cannot rebase.")"

if test -d "$apply_dir"
then
        type=am
        state_dir="$apply_dir"
elif test -d "$merge_dir"
then
        if test -f "$merge_dir"/interactive
        then
                type=interactive
                interactive_rebase=explicit
        else
                type=merge
        fi
        state_dir="$merge_dir"
fi
test -n "$type" && in_progress=t

total_argc=$#
while test $# != 0
do
        case "$1" in
        --no-verify)
                ok_to_skip_pre_rebase=yes
                ;;
        --verify)
                ok_to_skip_pre_rebase=
                ;;
        --continue|--skip|--abort|--quit|--edit-todo)
                test $total_argc -eq 2 || usage
                action=${1##--}
                ;;
        --onto=*)
                onto="${1#--onto=}"
                ;;
        --exec=*)
                cmd="${cmd}exec ${1#--exec=}${LF}"
                test -z "$interactive_rebase" && interactive_rebase=implied
                ;;
        --interactive)
                interactive_rebase=explicit
                ;;
        --keep-empty)
                keep_empty=yes
                ;;
        --no-keep-empty)
                keep_empty=
                ;;
        --preserve-merges)
                preserve_merges=t
                test -z "$interactive_rebase" && interactive_rebase=implied
                ;;
        --autosquash)
                autosquash=t
                ;;
        --no-autosquash)
                autosquash=
                ;;
        --fork-point)
                fork_point=t
                ;;
        --no-fork-point)
                fork_point=
                ;;
        --merge)
                do_merge=t
                ;;
        --strategy-option=*)
                strategy_opts="$strategy_opts $(git rev-parse --sq-quote "--${1#--strategy-option=}")"
                do_merge=t
                test -z "$strategy" && strategy=recursive
                ;;
        --strategy=*)
                strategy="${1#--strategy=}"
                do_merge=t
                ;;
        --no-stat)
                diffstat=
                ;;
        --stat)
                diffstat=t
                ;;
        --autostash)
                autostash=true
                ;;
        --no-autostash)
                autostash=false
                ;;
        --verbose)
                verbose=t
                diffstat=t
                GIT_QUIET=
                ;;
        --quiet)
                GIT_QUIET=t
                git_am_opt="$git_am_opt -q"
                verbose=
                diffstat=
                ;;
        --whitespace=*)
                git_am_opt="$git_am_opt --whitespace=${1#--whitespace=}"
                case "${1#--whitespace=}" in
                fix|strip)
                        force_rebase=t
                        ;;
                esac
                ;;
        --ignore-whitespace)
                git_am_opt="$git_am_opt $1"
                ;;
        --committer-date-is-author-date|--ignore-date|--signoff|--no-signoff)
                git_am_opt="$git_am_opt $1"
                force_rebase=t
                ;;
        -C*)
                git_am_opt="$git_am_opt $1"
                ;;
        --root)
                rebase_root=t
                ;;
        --force-rebase|--no-ff)
                force_rebase=t
                ;;
        --rerere-autoupdate|--no-rerere-autoupdate)
                allow_rerere_autoupdate="$1"
                ;;
        --gpg-sign)
                gpg_sign_opt=-S
                ;;
        --gpg-sign=*)
                gpg_sign_opt="-S${1#--gpg-sign=}"
                ;;
        --)
                shift
                break
                ;;
        *)
                usage
                ;;
        esac
        shift
done
test $# -gt 2 && usage

if test -n "$action"
then
        test -z "$in_progress" && die "$(gettext "No rebase in progress?")"
        # Only interactive rebase uses detailed reflog messages
        if test "$type" = interactive && test "$GIT_REFLOG_ACTION" = rebase
        then
                GIT_REFLOG_ACTION="rebase -i ($action)"
                export GIT_REFLOG_ACTION
        fi
fi

if test "$action" = "edit-todo" && test "$type" != "interactive"
then
        die "$(gettext "The --edit-todo action can only be used during interactive rebase.")"
fi

case "$action" in
continue)
        # Sanity check
        git rev-parse --verify HEAD >/dev/null ||
                die "$(gettext "Cannot read HEAD")"
        git update-index --ignore-submodules --refresh &&
        git diff-files --quiet --ignore-submodules || {
                echo "$(gettext "You must edit all merge conflicts and then
mark them as resolved using git add")"
                exit 1
        }
        read_basic_state
        run_specific_rebase
        ;;
skip)
        output git reset --hard HEAD || exit $?
        read_basic_state
        run_specific_rebase
        ;;
abort)
        git rerere clear
        read_basic_state
        case "$head_name" in
        refs/*)
                git symbolic-ref -m "rebase: aborting" HEAD $head_name ||
                die "$(eval_gettext "Could not move back to \$head_name")"
                ;;
        esac
        output git reset --hard $orig_head
        finish_rebase
        exit
        ;;
quit)
        exec rm -rf "$state_dir"
        ;;
edit-todo)
        run_specific_rebase
        ;;
esac

# Make sure no rebase is in progress
if test -n "$in_progress"
then
        state_dir_base=${state_dir##*/}
        cmd_live_rebase="git rebase (--continue | --abort | --skip)"
        cmd_clear_stale_rebase="rm -fr \"$state_dir\""
        die "
$(eval_gettext 'It seems that there is already a $state_dir_base directory, and
I wonder if you are in the middle of another rebase.  If that is the
case, please try
        $cmd_live_rebase
If that is not the case, please
        $cmd_clear_stale_rebase
and run me again.  I am stopping in case you still have something
valuable there.')"
fi

if test -n "$rebase_root" && test -z "$onto"
then
        test -z "$interactive_rebase" && interactive_rebase=implied
fi

if test -n "$interactive_rebase"
then
        type=interactive
        state_dir="$merge_dir"
elif test -n "$do_merge"
then
        type=merge
        state_dir="$merge_dir"
else
        type=am
        state_dir="$apply_dir"
fi

if test -t 2 && test -z "$GIT_QUIET"
then
        git_format_patch_opt="$git_format_patch_opt --progress"
fi

if test -z "$rebase_root"
then
        case "$#" in
        0)
                if ! upstream_name=$(git rev-parse --symbolic-full-name \
                        --verify -q @{upstream} 2>/dev/null)
                then
                        . git-parse-remote
                        error_on_missing_default_upstream "rebase" "rebase" \
                                "against" "git rebase $(gettext '<branch>')"
                fi

                test "$fork_point" = auto && fork_point=t
                ;;
        *)      upstream_name="$1"
                if test "$upstream_name" = "-"
                then
                        upstream_name="@{-1}"
                fi
                shift
                ;;
        esac
        upstream=$(peel_committish "${upstream_name}") ||
        die "$(eval_gettext "invalid upstream '\$upstream_name'")"
        upstream_arg="$upstream_name"
else
        if test -z "$onto"
        then
                empty_tree=$(git hash-object -t tree /dev/null)
                onto=$(git commit-tree $empty_tree </dev/null)
                squash_onto="$onto"
        fi
        unset upstream_name
        unset upstream
        test $# -gt 1 && usage
        upstream_arg=--root
fi

# Make sure the branch to rebase onto is valid.
onto_name=${onto-"$upstream_name"}
case "$onto_name" in
*...*)
        if      left=${onto_name%...*} right=${onto_name#*...} &&
                onto=$(git merge-base --all ${left:-HEAD} ${right:-HEAD})
        then
                case "$onto" in
                ?*"$LF"?*)
                        die "$(eval_gettext "\$onto_name: there are more than one merge bases")"
                        ;;
                '')
                        die "$(eval_gettext "\$onto_name: there is no merge base")"
                        ;;
                esac
        else
                die "$(eval_gettext "\$onto_name: there is no merge base")"
        fi
        ;;
*)
        onto=$(peel_committish "$onto_name") ||
        die "$(eval_gettext "Does not point to a valid commit: \$onto_name")"
        ;;
esac

# If the branch to rebase is given, that is the branch we will rebase
# $branch_name -- branch/commit being rebased, or HEAD (already detached)
# $orig_head -- commit object name of tip of the branch before rebasing
# $head_name -- refs/heads/<that-branch> or "detached HEAD"
switch_to=
case "$#" in
1)
        # Is it "rebase other $branchname" or "rebase other $commit"?
        branch_name="$1"
        switch_to="$1"

        # Is it a local branch?
        if git show-ref --verify --quiet -- "refs/heads/$branch_name" &&
           orig_head=$(git rev-parse -q --verify "refs/heads/$branch_name")
        then
                head_name="refs/heads/$branch_name"
        # If not is it a valid ref (branch or commit)?
        elif orig_head=$(git rev-parse -q --verify "$branch_name")
        then
                head_name="detached HEAD"

        else
                die "$(eval_gettext "fatal: no such branch/commit '\$branch_name'")"
        fi
        ;;
0)
        # Do not need to switch branches, we are already on it.
        if branch_name=$(git symbolic-ref -q HEAD)
        then
                head_name=$branch_name
                branch_name=$(expr "z$branch_name" : 'zrefs/heads/\(.*\)')
        else
                head_name="detached HEAD"
                branch_name=HEAD
        fi
        orig_head=$(git rev-parse --verify HEAD) || exit
        ;;
*)
        die "BUG: unexpected number of arguments left to parse"
        ;;
esac

if test "$fork_point" = t
then
        new_upstream=$(git merge-base --fork-point "$upstream_name" \
                        "${switch_to:-HEAD}")
        if test -n "$new_upstream"
        then
                restrict_revision=$new_upstream
        fi
fi

if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null
then
        stash_sha1=$(git stash create "autostash") ||
        die "$(gettext 'Cannot autostash')"

        mkdir -p "$state_dir" &&
        echo $stash_sha1 >"$state_dir/autostash" &&
        stash_abbrev=$(git rev-parse --short $stash_sha1) &&
        echo "$(eval_gettext 'Created autostash: $stash_abbrev')" &&
        git reset --hard
fi

require_clean_work_tree "rebase" "$(gettext "Please commit or stash them.")"

# Now we are rebasing commits $upstream..$orig_head (or with --root,
# everything leading up to $orig_head) on top of $onto

# Check if we are already based on $onto with linear history,
# but this should be done only when upstream and onto are the same
# and if this is not an interactive rebase.
mb=$(git merge-base "$onto" "$orig_head")
if test "$type" != interactive && test "$upstream" = "$onto" &&
        test "$mb" = "$onto" && test -z "$restrict_revision" &&
        # linear history?
        ! (git rev-list --parents "$onto".."$orig_head" | sane_grep " .* ") > /dev/null
then
        if test -z "$force_rebase"
        then
                # Lazily switch to the target branch if needed...
                test -z "$switch_to" ||
                GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $switch_to" \
                        git checkout -q "$switch_to" --
                if test "$branch_name" = "HEAD" &&
                         ! git symbolic-ref -q HEAD
                then
                        say "$(eval_gettext "HEAD is up to date.")"
                else
                        say "$(eval_gettext "Current branch \$branch_name is up to date.")"
                fi
                finish_rebase
                exit 0
        else
                if test "$branch_name" = "HEAD" &&
                         ! git symbolic-ref -q HEAD
                then
                        say "$(eval_gettext "HEAD is up to date, rebase forced.")"
                else
                        say "$(eval_gettext "Current branch \$branch_name is up to date, rebase forced.")"
                fi
        fi
fi

# If a hook exists, give it a chance to interrupt
run_pre_rebase_hook "$upstream_arg" "$@"

if test -n "$diffstat"
then
        if test -n "$verbose"
        then
                echo "$(eval_gettext "Changes from \$mb to \$onto:")"
        fi
        # We want color (if set), but no pager
        GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
fi

test "$type" = interactive && run_specific_rebase

# Detach HEAD and reset the tree
say "$(gettext "First, rewinding head to replay your work on top of it...")"

GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name" \
        git checkout -q "$onto^0" || die "could not detach HEAD"
git update-ref ORIG_HEAD $orig_head

# If the $onto is a proper descendant of the tip of the branch, then
# we just fast-forwarded.
if test "$mb" = "$orig_head"
then
        say "$(eval_gettext "Fast-forwarded \$branch_name to \$onto_name.")"
        move_to_original_branch
        finish_rebase
        exit 0
fi

if test -n "$rebase_root"
then
        revisions="$onto..$orig_head"
else
        revisions="${restrict_revision-$upstream}..$orig_head"
fi

run_specific_rebase