drmingdrmer/git-gotofix

## git-gotofix
#!/bin/sh

usage()
{
    cat >&2 <<-END
	usage: git gotofix <fn>

	    Fix <fn> at the commit where <fn> is lastly modified.
	    And get HEAD back to where before using git-gotofix.

	    This script accomplish this by running a customized
	    git-rebase--interactive.

	Example:

	    # go to commit in which <fn> was modified. And VIM is
	    # automatically opened this file.
	    git gotofix <fn>

	    # hack..hack..

	    # get fix ready.
	    git add <fn>

	    # apply changes and go back to where you started.
	    git rebase --continue
	    # or discard changes and restore.
	    git rebase --abort
	END
}


clr()
{
    # clr light read blabla

    local black=0
    local white=7
    local red=1
    local green=2
    local brown=3
    local blue=4
    local purple=5
    local cyan=6

    local light=""
    local color=$1
    shift

    if [ "$color" == "light" ]; then
        light="tput bold; "
        color=$1
        shift
    fi

    local code=$(eval 'echo $'$color)
    local cmd="${light}tput setaf $code"
    local color_str="$(eval "$cmd")"

    echo $color_str"$@""$(tput sgr0)"
}

shlib_init_colors()
{
    Black="$(                   tput setaf 0)"
    BlackBG="$(                 tput setab 0)"
    DarkGrey="$(     tput bold; tput setaf 0)"
    LightGrey="$(               tput setaf 7)"
    LightGreyBG="$(             tput setab 7)"
    White="$(        tput bold; tput setaf 7)"
    Red="$(                     tput setaf 1)"
    RedBG="$(                   tput setab 1)"
    LightRed="$(     tput bold; tput setaf 1)"
    Green="$(                   tput setaf 2)"
    GreenBG="$(                 tput setab 2)"
    LightGreen="$(   tput bold; tput setaf 2)"
    Brown="$(                   tput setaf 3)"
    BrownBG="$(                 tput setab 3)"
    Yellow="$(       tput bold; tput setaf 3)"
    Blue="$(                    tput setaf 4)"
    BlueBG="$(                  tput setab 4)"
    LightBlue="$(    tput bold; tput setaf 4)"
    Purple="$(                  tput setaf 5)"
    PurpleBG="$(                tput setab 5)"
    Pink="$(         tput bold; tput setaf 5)"
    Cyan="$(                    tput setaf 6)"
    CyanBG="$(                  tput setab 6)"
    LightCyan="$(    tput bold; tput setaf 6)"
    NC="$(                      tput sgr0)" # No Color
}


screen_width()
{
    local chr="${1--}"
    chr="${chr:0:1}"

    local width=$(tput cols 2||echo 80)
    width="${COLUMNS:-$width}"

    echo $width
}

hr()
{
    # generate a full screen width horizontal ruler
    local width=$(screen_width)

    printf -vl "%${width}s\n" && echo ${l// /$chr};
}

remove_color()
{
    # remove color control chars from stdin or first argument

    local sed=gsed
    which -s $sed || sed=sed

    local s="$1"
    if [ -z "$s" ]; then
        $sed -r "s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[mGK]//g"
    else
        echo "$s" | remove_color
    fi

}

text_hr()
{
    # generate a full screen width sperator line with text.
    # text_hr "-" "a title"
    # > a title -----------------------------------------
    #
    # variable LR=l|m|r controls alignment

    local chr="$1"
    shift

    local bb="$(echo "$@" | remove_color)"
    local text_len=${#bb}

    local width=$(screen_width)
    let width=width-text_len

    local lr=${LR-m}
    case $lr in
        m)
            let left=width/2
            let right=width-left
            echo "$(printf -vl "%${left}s\n" && echo ${l// /$chr})$@$(printf -vl "%${right}s\n" && echo ${l// /$chr})"
            ;;
        r)

            echo "$(printf -vl "%${width}s\n" && echo ${l// /$chr})$@"
            ;;
        *)
            # l by default
            echo "$@$(printf -vl "%${width}s\n" && echo ${l// /$chr})"
            ;;
    esac

}


SHLIB_LOG_VERBOSE=1
SHLIB_LOG_FORMAT='[$(date +"%Y-%m-%d %H:%M:%S")] $level $title $mes'

die()
{
    err "$@" >&2
    exit 1
}
die_empty()
{
    if test -z "$1"
    then
        shift
        die empty: "$@"
    fi
}

set_verbose()
{
    SHLIB_LOG_VERBOSE=${1-1}
}

log()
{
    local color="$1"
    local title="$2"
    local level="$_LOG_LEVEL"
    shift
    shift

    local mes="$@"
    local NC="$(tput sgr0)"

    if [ -t 1 ]; then
        title="${color}${title}${NC}"
        level="${color}${level}${NC}"
    fi
    eval "echo \"$SHLIB_LOG_FORMAT\""
}
dd()
{
    debug "$@"
}
debug()
{
    if [ ".$SHLIB_LOG_VERBOSE" = ".1" ]; then
        local LightCyan="$(tput bold ; tput setaf 6)"
        _LOG_LEVEL=DEBUG log "$LightCyan" "$@" >&2
    fi
}
info()
{
    local Brown="$(tput setaf 3)"
    _LOG_LEVEL=" INFO" log "$Brown" "$@"
}
ok() {
    local Green="$(tput setaf 2)"
    _LOG_LEVEL="   OK" log "${Green}" "$@"
}
err() {
    local Red="$(tput setaf 1)"
    _LOG_LEVEL="ERROR" log "${Red}" "$@"
}

git_hash()
{
    git rev-parse $1 \
        || die "'git_hash $@'"
}
git_is_merge()
{
    test $(git cat-file -p "$1" | grep "^parent " | wc -l) -gt 1
}
git_parents()
{
    git rev-list --parents -n 1 ${1-HEAD} | { read self parents; echo $parents; }
}
git_rev_list()
{
    # --parents
    # print parent in this form:
    #     <commit> <parent-1> <parent-2> ..

    git rev-list \
        --reverse \
        --topo-order \
        --default HEAD \
        --simplify-merges \
        "$@" \
        || die "'git rev-list $@'"
}
git_tree_hash()
{
    git rev-parse "$1^{tree}"
}
git_ver()
{
    local git_version=$(git --version | awk '{print $NF}')
    local git_version_1=${git_version%%.*}
    local git_version_2=${git_version#*.}
    git_version_2=${git_version_2%%.*}

    printf "%03d%03d" $git_version_1 $git_version_2
}
git_working_root()
{
    git rev-parse --show-toplevel
}

git_rev_exist()
{
    git rev-parse --verify --quiet "$1" >/dev/null
}

git_branch_default_remote()
{
    local branchname=$1
    git config --get branch.${branchname}.remote
}
git_branch_default_upstream_ref()
{
    local branchname=$1
    git config --get branch.${branchname}.merge
}
git_branch_default_upstream()
{
    git rev-parse --abbrev-ref --symbolic-full-name "$1"@{upstream}

    # OR
    # git_branch_default_upstream_ref "$@" | sed 's/^refs\/heads\///'
}
git_branch_exist()
{
    git_rev_exist "refs/heads/$1"
}

git_head_branch()
{
    git symbolic-ref --short HEAD
}

git_commit_date()
{

    # git_commit_date author|commit <ref> [date-format]

    # by default output author-date
    local what_date="%ad"
    if [ "$1" = "commit" ]; then
        # commit date instead of author date
        what_date="%cd"
    fi
    shift

    local ref=$1
    shift

    local fmt="%Y-%m-%d %H:%M:%S"
    if [ "$#" -gt 0 ]; then
        fmt="$1"
    fi
    shift

    git log -n1 --format="$what_date" --date=format:"$fmt" "$ref"
}
git_commit_copy()
{
    # We're going to set some environment vars here, so
    # do it in a subshell to get rid of them safely later
    dd copy_commit "{$1}" "{$2}" "{$3}"
    git log -1 --pretty=format:'%an%n%ae%n%ad%n%cn%n%ce%n%cd%n%s%n%n%b' "$1" |
    (
    read GIT_AUTHOR_NAME
    read GIT_AUTHOR_EMAIL
    read GIT_AUTHOR_DATE
    read GIT_COMMITTER_NAME
    read GIT_COMMITTER_EMAIL
    read GIT_COMMITTER_DATE
    export  GIT_AUTHOR_NAME \
        GIT_AUTHOR_EMAIL \
        GIT_AUTHOR_DATE \
        GIT_COMMITTER_NAME \
        GIT_COMMITTER_EMAIL \
        GIT_COMMITTER_DATE

    # (echo -n "$annotate"; cat ) |

    git commit-tree "$2" $3  # reads the rest of stdin
    ) || die "Can't copy commit $1"
}

git_object_type()
{
    # $0 ref|hash
    # output "commit", "tree" etc
    git cat-file -t "$@" 2>/dev/null
}
git_object_add_by_commit_path()
{
    # add an blob or tree object to target_path in index
    # the object to add is specified by commit and path
    local target_path="$1"
    local src_commit="$2"
    local src_path="$3"

    local src_dir="$(dirname "$src_path")/"
    local src_name="$(basename "$src_path")"
    local src_treeish="$(git rev-parse "$src_commit:$src_dir")"

    git_object_add_by_tree_name "$target_path" "$src_treeish" "$src_name"

}
git_object_add_by_tree_name()
{
    # add an blob or tree object to target_path in index
    local target_path="$1"
    local src_treeish="$2"
    local src_name="$3"

    dd "arg: target_path: ($target_path) src_treeish: ($src_treeish) src_name: ($src_name)"

    local target_dir="$(dirname $target_path)/"
    local target_fn="$(basename $target_path)"
    local treeish

    if [ -z "$src_name" ] || [ "$src_name" = "." ] || [ "$src_name" = "./" ]; then
        treeish="$src_treeish"
    else
        treeish=$(git ls-tree "$src_treeish" "$src_name" | awk '{print $3}')

        if [ -z "$treeish" ]; then
            die "source treeish not found: in tree: ($src_treeish) name: ($src_name)"
        fi
    fi

    dd "hash of object to add is: $treeish"

    if [ "$(git_object_type $treeish)" = "blob" ]; then
        # the treeish imported is a file, not a dir
        # first create a wrapper tree or replace its containing tree

        dd "object to add is blob"

        local dir_treeish
        local target_dir_treeish="$(git rev-parse "HEAD:$target_dir")"
        if [ -n "target_dir_treeish" ]; then
            dir_treeish="$(git rev-parse "HEAD:$target_dir")"
            dd "target dir presents: $target_dir"

        else
            dd "target dir absent"
            dir_treeish=""
        fi

        treeish=$(git_tree_add_blob "$dir_treeish" "$target_fn" $src_treeish $src_name) || die create wrapper treeish
        target_path="$target_dir"

        dd "wrapper treeish: $treeish"
        dd "target_path set to: $target_path"
    else
        dd "object to add is tree"
    fi

    git_treeish_add_to_prefix "$target_path" "$treeish"
}

git_treeish_add_to_prefix()
{
    local target_path="$1"
    local treeish="$2"

    dd treeish content:
    git ls-tree $treeish

    git rm "$target_path" -r --cached || dd removing target "$target_path"

    if [ "$target_path" = "./" ]; then
        git read-tree "$treeish" \
            || die "read-tree $target_path $treeish"
    else
        git read-tree --prefix="$target_path" "$treeish" \
            || die "read-tree $target_path $treeish"
    fi
}

git_tree_add_tree()
{
    # output new tree hash in stdout
    # treeish can be empty
    local treeish="$1"
    local target_fn="$2"
    local item_hash="$3"
    local item_name="$4"

    {
        if [ -n "$treeish" ]; then
            git ls-tree "$treeish" \
                | fgrep -v "	$item_name"
        fi

        cat "040000 tree $item_hash	$target_fn"
    } | git mktree
}
git_tree_add_blob()
{
    # output new tree hash in stdout
    # treeish can be empty
    local treeish="$1"
    local target_fn="$2"
    local blob_treeish="$3"
    local blob_name="$4"

    {
        if [ -n "$treeish" ]; then
            git ls-tree "$treeish" \
                | fgrep -v "	$target_fn"
        fi

        git ls-tree "$blob_treeish" "$blob_name" \
            | awk -v target_fn="$target_fn" -F"	" '{print $1"	"target_fn}'
    } | git mktree
}

git_workdir_save()
{
    local index_hash=$(git write-tree)

    # add modified file to index and read index tree
    git add -u
    local working_hash=$(git write-tree)

    # restore index tree
    git read-tree $index_hash

    echo $index_hash $working_hash
}
git_workdir_load()
{
    local index_hash=$1
    local working_hash=$2

    git_object_type $index_hash || die "invalid index hash: $index_hash"
    git_object_type $working_hash || die "invalid workdir hash: $working_hash"

    # First create a temp commit to restore working tree.
    #
    # git-read-index to index and git-reset does not work because deleted file in
    # index does not apply to working tree.
    #
    # But there is an issue with this:
    #   git checkout --orphan br
    #   git_workdir_load
    # would fails, because ORIG_HEAD is not a commit.

    local working_commit=$(echo "x" | git commit-tree $working_hash) || die get working commit
    git reset --hard $working_commit || die reset to tmp commit
    git reset --soft ORIG_HEAD || die reset to ORIG_HEAD
    git read-tree $index_hash || die "load saved index tree from $index_hash"
}
git_workdir_is_clean()
{
    local untracked="$1"
    if [ "$untracked" == "untracked" ]; then
        [ -z "$(git status --porcelain)" ]
    else
        [ -z "$(git status --porcelain --untracked-files=no)" ]
    fi
}

git_copy_commit()
{
    git_commit_copy "$@"
}

git_diff_ln_new()
{
    # output changed line number of a file: <from> <end>; inclusive:
    # 27 28
    # 307 309
    # 350 350
    #
    # Usage:
    #
    #   diff working tree with HEAD:
    #       git_diff_ln_new HEAD -- <fn>
    #
    #   diff working tree with staged:
    #       git_diff_ln_new -- <fn>
    #
    #   diff staged(cached) with HEAD:
    #       git_diff_ln_new --cached -- <fn>
    #
    # in git-diff output:
    # for add lines:
    # @@ -53 +72,8
    #
    # for remove lines:
    # @@ -155 +179,0

    git diff -U0 "$@" \
        | grep '^@@' \
        | awk '{

    # @@ -155 +179,0
    # $1 $2   $3

    l = $3
    gsub("^+", "", l)

    # add default offset: ",1"
    split(l",1", x, ",")

    # inclusive line range:
    x[2] = x[1] + x[2] - 1

    # line remove format: @@ -155, +179,0
    # do need to output line range for removed.
    if (x[2] >= x[1]) {
        print x[1] " " x[2]
    }

}'
}


os_detect()
{
    local os
    case $(uname -s) in
        Linux)
            os=linux ;;
        *[bB][sS][dD])
            os=bsd ;;
        Darwin)
            os=mac ;;
        *)
            os=unix ;;
    esac
    echo $os
}

mac_ac_power_connection()
{
    #  Connected: (Yes|No)
    system_profiler SPPowerDataType \
        | sed '1,/^ *AC Charger Information:/d' \
        | grep Connected:
}


mac_power()
{

    # $0 is-battery          exit code 0 if using battery.
    # $0 is-ac-power         exit code 0 if using ac power.

    local cmd="$1"
    local os=$(os_detect)

    if [ "$os" != "mac" ]; then
        err "not mac but: $os"
        return 1
    fi

    case $cmd in

        is-battery)
            mac_ac_power_connection | grep -q No
            ;;

        is-ac-power)
            mac_ac_power_connection | grep -q Yes
            ;;

        *)
            err "invalid cmd: $cmd"
            return 1
            ;;
    esac
}

fn_match()
{
    # $0 a.txt *.txt
    case "$1" in
        $2)
            return 0
            ;;
    esac
    return 1
}

obj=$1
is_obj_file=0
linenr=0
ori_linenr=0
stashed=0


if [ -z "$obj" ] || [ "$obj" = "-h" ] || [ "$obj" = "--help" ]; then
    usage
    exit 1
fi

if git diff --name-only --relative HEAD --quiet; then
    :
else
    git stash
    stashed=1
fi

if [ "$(git_object_type $obj)" = "commit" ]; then
    commit=$obj
else
    # it is a file path
    # find the latest commit touched this file
    is_obj_file=1
    if [ ".$2" != "." ]; then
        # gotofix <fn> <linenr>
        # get the commit last time edited this line
        commit=$(git blame "$obj" -L "$2",+1 -p | head -n1 | { read sha other; echo $sha; })
        ori_linenr=$(git blame "$obj" -L "$2",+1 -p | head -n1 | { read sha ori_linenr other; echo $ori_linenr; })
        info "going to commit: $commit $ori_linenr"
    else
        # find the last commit that changed any line of this file
        commit=$(git log -n1 --format="%h" "$obj")
    fi
fi

sed_remove_after_blank="'"'/^$/,$d'"'"

# only replace the first line
sed_edit_commit="1 s/pick /edit /"
# add quote
sed_edit_commit="'$sed_edit_commit'"

GIT_EDITOR='f(){ cat "$1" | sed '$sed_remove_after_blank' | sed '$sed_edit_commit' >"$1-tmp"; mv "$1-tmp" $1; }; f' \
    git rebase --interactive $commit~

if [ "$stashed" == "1" ]; then
    git stash pop || die fail to pop stash
fi

if [ "$is_obj_file" = "1" ]; then
    vim "$obj" +$ori_linenr -c "normal zR"
    git rebase --continue
fi
	#!/bin/sh

	usage()
	{
	cat >&2 <<-END
	usage: git gotofix <fn>

	Fix <fn> at the commit where <fn> is lastly modified.
	And get HEAD back to where before using git-gotofix.

	This script accomplish this by running a customized
	git-rebase--interactive.

	Example:

	# go to commit in which <fn> was modified. And VIM is
	# automatically opened this file.
	git gotofix <fn>

	# hack..hack..

	# get fix ready.
	git add <fn>

	# apply changes and go back to where you started.
	git rebase --continue
	# or discard changes and restore.
	git rebase --abort
	END
	}



	clr()
	{
	# clr light read blabla

	local black=0
	local white=7
	local red=1
	local green=2
	local brown=3
	local blue=4
	local purple=5
	local cyan=6

	local light=""
	local color=$1
	shift

	if [ "$color" == "light" ]; then
	light="tput bold; "
	color=$1
	shift
	fi

	local code=$(eval 'echo $'$color)
	local cmd="${light}tput setaf $code"
	local color_str="$(eval "$cmd")"

	echo $color_str"$@""$(tput sgr0)"
	}

	shlib_init_colors()
	{
	Black="$( tput setaf 0)"
	BlackBG="$( tput setab 0)"
	DarkGrey="$( tput bold; tput setaf 0)"
	LightGrey="$( tput setaf 7)"
	LightGreyBG="$( tput setab 7)"
	White="$( tput bold; tput setaf 7)"
	Red="$( tput setaf 1)"
	RedBG="$( tput setab 1)"
	LightRed="$( tput bold; tput setaf 1)"
	Green="$( tput setaf 2)"
	GreenBG="$( tput setab 2)"
	LightGreen="$( tput bold; tput setaf 2)"
	Brown="$( tput setaf 3)"
	BrownBG="$( tput setab 3)"
	Yellow="$( tput bold; tput setaf 3)"
	Blue="$( tput setaf 4)"
	BlueBG="$( tput setab 4)"
	LightBlue="$( tput bold; tput setaf 4)"
	Purple="$( tput setaf 5)"
	PurpleBG="$( tput setab 5)"
	Pink="$( tput bold; tput setaf 5)"
	Cyan="$( tput setaf 6)"
	CyanBG="$( tput setab 6)"
	LightCyan="$( tput bold; tput setaf 6)"
	NC="$( tput sgr0)" # No Color
	}


	screen_width()
	{
	local chr="${1--}"
	chr="${chr:0:1}"

	local width=$(tput cols 2\|\|echo 80)
	width="${COLUMNS:-$width}"

	echo $width
	}

	hr()
	{
	# generate a full screen width horizontal ruler
	local width=$(screen_width)

	printf -vl "%${width}s\n" && echo ${l// /$chr};
	}

	remove_color()
	{
	# remove color control chars from stdin or first argument

	local sed=gsed
	which -s $sed \|\| sed=sed

	local s="$1"
	if [ -z "$s" ]; then
	$sed -r "s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[mGK]//g"
	else
	echo "$s" \| remove_color
	fi

	}

	text_hr()
	{
	# generate a full screen width sperator line with text.
	# text_hr "-" "a title"
	# > a title -----------------------------------------
	#
	# variable LR=l\|m\|r controls alignment

	local chr="$1"
	shift

	local bb="$(echo "$@" \| remove_color)"
	local text_len=${#bb}

	local width=$(screen_width)
	let width=width-text_len

	local lr=${LR-m}
	case $lr in
	m)
	let left=width/2
	let right=width-left
	echo "$(printf -vl "%${left}s\n" && echo ${l// /$chr})$@$(printf -vl "%${right}s\n" && echo ${l// /$chr})"
	;;
	r)

	echo "$(printf -vl "%${width}s\n" && echo ${l// /$chr})$@"
	;;
	*)
	# l by default
	echo "$@$(printf -vl "%${width}s\n" && echo ${l// /$chr})"
	;;
	esac

	}



	SHLIB_LOG_VERBOSE=1
	SHLIB_LOG_FORMAT='[$(date +"%Y-%m-%d %H:%M:%S")] $level $title $mes'

	die()
	{
	err "$@" >&2
	exit 1
	}
	die_empty()
	{
	if test -z "$1"
	then
	shift
	die empty: "$@"
	fi
	}

	set_verbose()
	{
	SHLIB_LOG_VERBOSE=${1-1}
	}

	log()
	{
	local color="$1"
	local title="$2"
	local level="$_LOG_LEVEL"
	shift
	shift

	local mes="$@"
	local NC="$(tput sgr0)"

	if [ -t 1 ]; then
	title="${color}${title}${NC}"
	level="${color}${level}${NC}"
	fi
	eval "echo \"$SHLIB_LOG_FORMAT\""
	}
	dd()
	{
	debug "$@"
	}
	debug()
	{
	if [ ".$SHLIB_LOG_VERBOSE" = ".1" ]; then
	local LightCyan="$(tput bold ; tput setaf 6)"
	_LOG_LEVEL=DEBUG log "$LightCyan" "$@" >&2
	fi
	}
	info()
	{
	local Brown="$(tput setaf 3)"
	_LOG_LEVEL=" INFO" log "$Brown" "$@"
	}
	ok() {
	local Green="$(tput setaf 2)"
	_LOG_LEVEL=" OK" log "${Green}" "$@"
	}
	err() {
	local Red="$(tput setaf 1)"
	_LOG_LEVEL="ERROR" log "${Red}" "$@"
	}

	git_hash()
	{
	git rev-parse $1 \
	\|\| die "'git_hash $@'"
	}
	git_is_merge()
	{
	test $(git cat-file -p "$1" \| grep "^parent " \| wc -l) -gt 1
	}
	git_parents()
	{
	git rev-list --parents -n 1 ${1-HEAD} \| { read self parents; echo $parents; }
	}
	git_rev_list()
	{
	# --parents
	# print parent in this form:
	# <commit> <parent-1> <parent-2> ..

	git rev-list \
	--reverse \
	--topo-order \
	--default HEAD \
	--simplify-merges \
	"$@" \
	\|\| die "'git rev-list $@'"
	}
	git_tree_hash()
	{
	git rev-parse "$1^{tree}"
	}
	git_ver()
	{
	local git_version=$(git --version \| awk '{print $NF}')
	local git_version_1=${git_version%%.*}
	local git_version_2=${git_version#*.}
	git_version_2=${git_version_2%%.*}

	printf "%03d%03d" $git_version_1 $git_version_2
	}
	git_working_root()
	{
	git rev-parse --show-toplevel
	}

	git_rev_exist()
	{
	git rev-parse --verify --quiet "$1" >/dev/null
	}

	git_branch_default_remote()
	{
	local branchname=$1
	git config --get branch.${branchname}.remote
	}
	git_branch_default_upstream_ref()
	{
	local branchname=$1
	git config --get branch.${branchname}.merge
	}
	git_branch_default_upstream()
	{
	git rev-parse --abbrev-ref --symbolic-full-name "$1"@{upstream}

	# OR
	# git_branch_default_upstream_ref "$@" \| sed 's/^refs\/heads\///'
	}
	git_branch_exist()
	{
	git_rev_exist "refs/heads/$1"
	}

	git_head_branch()
	{
	git symbolic-ref --short HEAD
	}

	git_commit_date()
	{

	# git_commit_date author\|commit <ref> [date-format]

	# by default output author-date
	local what_date="%ad"
	if [ "$1" = "commit" ]; then
	# commit date instead of author date
	what_date="%cd"
	fi
	shift

	local ref=$1
	shift

	local fmt="%Y-%m-%d %H:%M:%S"
	if [ "$#" -gt 0 ]; then
	fmt="$1"
	fi
	shift

	git log -n1 --format="$what_date" --date=format:"$fmt" "$ref"
	}
	git_commit_copy()
	{
	# We're going to set some environment vars here, so
	# do it in a subshell to get rid of them safely later
	dd copy_commit "{$1}" "{$2}" "{$3}"
	git log -1 --pretty=format:'%an%n%ae%n%ad%n%cn%n%ce%n%cd%n%s%n%n%b' "$1" \|
	(
	read GIT_AUTHOR_NAME
	read GIT_AUTHOR_EMAIL
	read GIT_AUTHOR_DATE
	read GIT_COMMITTER_NAME
	read GIT_COMMITTER_EMAIL
	read GIT_COMMITTER_DATE
	export GIT_AUTHOR_NAME \
	GIT_AUTHOR_EMAIL \
	GIT_AUTHOR_DATE \
	GIT_COMMITTER_NAME \
	GIT_COMMITTER_EMAIL \
	GIT_COMMITTER_DATE

	# (echo -n "$annotate"; cat ) \|

	git commit-tree "$2" $3 # reads the rest of stdin
	) \|\| die "Can't copy commit $1"
	}

	git_object_type()
	{
	# $0 ref\|hash
	# output "commit", "tree" etc
	git cat-file -t "$@" 2>/dev/null
	}
	git_object_add_by_commit_path()
	{
	# add an blob or tree object to target_path in index
	# the object to add is specified by commit and path
	local target_path="$1"
	local src_commit="$2"
	local src_path="$3"

	local src_dir="$(dirname "$src_path")/"
	local src_name="$(basename "$src_path")"
	local src_treeish="$(git rev-parse "$src_commit:$src_dir")"

	git_object_add_by_tree_name "$target_path" "$src_treeish" "$src_name"

	}
	git_object_add_by_tree_name()
	{
	# add an blob or tree object to target_path in index
	local target_path="$1"
	local src_treeish="$2"
	local src_name="$3"

	dd "arg: target_path: ($target_path) src_treeish: ($src_treeish) src_name: ($src_name)"

	local target_dir="$(dirname $target_path)/"
	local target_fn="$(basename $target_path)"
	local treeish

	if [ -z "$src_name" ] \|\| [ "$src_name" = "." ] \|\| [ "$src_name" = "./" ]; then
	treeish="$src_treeish"
	else
	treeish=$(git ls-tree "$src_treeish" "$src_name" \| awk '{print $3}')

	if [ -z "$treeish" ]; then
	die "source treeish not found: in tree: ($src_treeish) name: ($src_name)"
	fi
	fi

	dd "hash of object to add is: $treeish"

	if [ "$(git_object_type $treeish)" = "blob" ]; then
	# the treeish imported is a file, not a dir
	# first create a wrapper tree or replace its containing tree

	dd "object to add is blob"

	local dir_treeish
	local target_dir_treeish="$(git rev-parse "HEAD:$target_dir")"
	if [ -n "target_dir_treeish" ]; then
	dir_treeish="$(git rev-parse "HEAD:$target_dir")"
	dd "target dir presents: $target_dir"

	else
	dd "target dir absent"
	dir_treeish=""
	fi

	treeish=$(git_tree_add_blob "$dir_treeish" "$target_fn" $src_treeish $src_name) \|\| die create wrapper treeish
	target_path="$target_dir"

	dd "wrapper treeish: $treeish"
	dd "target_path set to: $target_path"
	else
	dd "object to add is tree"
	fi

	git_treeish_add_to_prefix "$target_path" "$treeish"
	}

	git_treeish_add_to_prefix()
	{
	local target_path="$1"
	local treeish="$2"

	dd treeish content:
	git ls-tree $treeish

	git rm "$target_path" -r --cached \|\| dd removing target "$target_path"

	if [ "$target_path" = "./" ]; then
	git read-tree "$treeish" \
	\|\| die "read-tree $target_path $treeish"
	else
	git read-tree --prefix="$target_path" "$treeish" \
	\|\| die "read-tree $target_path $treeish"
	fi
	}

	git_tree_add_tree()
	{
	# output new tree hash in stdout
	# treeish can be empty
	local treeish="$1"
	local target_fn="$2"
	local item_hash="$3"
	local item_name="$4"

	{
	if [ -n "$treeish" ]; then
	git ls-tree "$treeish" \
	\| fgrep -v " $item_name"
	fi

	cat "040000 tree $item_hash $target_fn"
	} \| git mktree
	}
	git_tree_add_blob()
	{
	# output new tree hash in stdout
	# treeish can be empty
	local treeish="$1"
	local target_fn="$2"
	local blob_treeish="$3"
	local blob_name="$4"

	{
	if [ -n "$treeish" ]; then
	git ls-tree "$treeish" \
	\| fgrep -v " $target_fn"
	fi

	git ls-tree "$blob_treeish" "$blob_name" \
	\| awk -v target_fn="$target_fn" -F" " '{print $1" "target_fn}'
	} \| git mktree
	}

	git_workdir_save()
	{
	local index_hash=$(git write-tree)

	# add modified file to index and read index tree
	git add -u
	local working_hash=$(git write-tree)

	# restore index tree
	git read-tree $index_hash

	echo $index_hash $working_hash
	}
	git_workdir_load()
	{
	local index_hash=$1
	local working_hash=$2

	git_object_type $index_hash \|\| die "invalid index hash: $index_hash"
	git_object_type $working_hash \|\| die "invalid workdir hash: $working_hash"

	# First create a temp commit to restore working tree.
	#
	# git-read-index to index and git-reset does not work because deleted file in
	# index does not apply to working tree.
	#
	# But there is an issue with this:
	# git checkout --orphan br
	# git_workdir_load
	# would fails, because ORIG_HEAD is not a commit.

	local working_commit=$(echo "x" \| git commit-tree $working_hash) \|\| die get working commit
	git reset --hard $working_commit \|\| die reset to tmp commit
	git reset --soft ORIG_HEAD \|\| die reset to ORIG_HEAD
	git read-tree $index_hash \|\| die "load saved index tree from $index_hash"
	}
	git_workdir_is_clean()
	{
	local untracked="$1"
	if [ "$untracked" == "untracked" ]; then
	[ -z "$(git status --porcelain)" ]
	else
	[ -z "$(git status --porcelain --untracked-files=no)" ]
	fi
	}

	git_copy_commit()
	{
	git_commit_copy "$@"
	}

	git_diff_ln_new()
	{
	# output changed line number of a file: <from> <end>; inclusive:
	# 27 28
	# 307 309
	# 350 350
	#
	# Usage:
	#
	# diff working tree with HEAD:
	# git_diff_ln_new HEAD -- <fn>
	#
	# diff working tree with staged:
	# git_diff_ln_new -- <fn>
	#
	# diff staged(cached) with HEAD:
	# git_diff_ln_new --cached -- <fn>
	#
	# in git-diff output:
	# for add lines:
	# @@ -53 +72,8
	#
	# for remove lines:
	# @@ -155 +179,0

	git diff -U0 "$@" \
	\| grep '^@@' \
	\| awk '{

	# @@ -155 +179,0
	# $1 $2 $3

	l = $3
	gsub("^+", "", l)

	# add default offset: ",1"
	split(l",1", x, ",")

	# inclusive line range:
	x[2] = x[1] + x[2] - 1

	# line remove format: @@ -155, +179,0
	# do need to output line range for removed.
	if (x[2] >= x[1]) {
	print x[1] " " x[2]
	}

	}'
	}




	os_detect()
	{
	local os
	case $(uname -s) in
	Linux)
	os=linux ;;
	*[bB][sS][dD])
	os=bsd ;;
	Darwin)
	os=mac ;;
	*)
	os=unix ;;
	esac
	echo $os
	}

	mac_ac_power_connection()
	{
	# Connected: (Yes\|No)
	system_profiler SPPowerDataType \
	\| sed '1,/^ *AC Charger Information:/d' \
	\| grep Connected:
	}


	mac_power()
	{

	# $0 is-battery exit code 0 if using battery.
	# $0 is-ac-power exit code 0 if using ac power.

	local cmd="$1"
	local os=$(os_detect)

	if [ "$os" != "mac" ]; then
	err "not mac but: $os"
	return 1
	fi

	case $cmd in

	is-battery)
	mac_ac_power_connection \| grep -q No
	;;

	is-ac-power)
	mac_ac_power_connection \| grep -q Yes
	;;

	*)
	err "invalid cmd: $cmd"
	return 1
	;;
	esac
	}

	fn_match()
	{
	# $0 a.txt *.txt
	case "$1" in
	$2)
	return 0
	;;
	esac
	return 1
	}

	obj=$1
	is_obj_file=0
	linenr=0
	ori_linenr=0
	stashed=0


	if [ -z "$obj" ] \|\| [ "$obj" = "-h" ] \|\| [ "$obj" = "--help" ]; then
	usage
	exit 1
	fi

	if git diff --name-only --relative HEAD --quiet; then
	:
	else
	git stash
	stashed=1
	fi

	if [ "$(git_object_type $obj)" = "commit" ]; then
	commit=$obj
	else
	# it is a file path
	# find the latest commit touched this file
	is_obj_file=1
	if [ ".$2" != "." ]; then
	# gotofix <fn> <linenr>
	# get the commit last time edited this line
	commit=$(git blame "$obj" -L "$2",+1 -p \| head -n1 \| { read sha other; echo $sha; })
	ori_linenr=$(git blame "$obj" -L "$2",+1 -p \| head -n1 \| { read sha ori_linenr other; echo $ori_linenr; })
	info "going to commit: $commit $ori_linenr"
	else
	# find the last commit that changed any line of this file
	commit=$(git log -n1 --format="%h" "$obj")
	fi
	fi

	sed_remove_after_blank="'"'/^$/,$d'"'"

	# only replace the first line
	sed_edit_commit="1 s/pick /edit /"
	# add quote
	sed_edit_commit="'$sed_edit_commit'"

	GIT_EDITOR='f(){ cat "$1" \| sed '$sed_remove_after_blank' \| sed '$sed_edit_commit' >"$1-tmp"; mv "$1-tmp" $1; }; f' \
	git rebase --interactive $commit~

	if [ "$stashed" == "1" ]; then
	git stash pop \|\| die fail to pop stash
	fi

	if [ "$is_obj_file" = "1" ]; then
	vim "$obj" +$ori_linenr -c "normal zR"
	git rebase --continue
	fi