guilt-pop

#!/bin/sh
#
# Copyright (c) Josef "Jeff" Sipek, 2006-2013
#

USAGE="[-f] [-a | --all | -n <num> | <patchname>]"
if [ -z "$GUILT_VERSION" ]; then
	echo "Invoking `basename "$0"` directly is no longer supported." >&2
	exit 1
fi

_main() {

while [ $# -gt 0 ]; do
	case "$1" in
		-f)
			force=t
			;;
		-a|--all)
			all=t
			;;
		-n)
			num=t
			;;
		*)
			break
			;;
	esac
	shift
done

# "guilt-pop" or "guilt-pop foo" or "guilt-pop -n foo"
if [ -z "$all" ] && [ $# -gt 1 ]; then
	usage
fi

# "guilt-pop -n foo"
if [ ! -z "$num" ]; then
	if [ $# -gt 1 ] || [ $# -eq 0 ]; then
		usage
	fi
fi

# "guilt-pop -a"
if [ ! -z "$all" ] && [ $# -gt 0 ]; then
	usage
fi

patch="$1"
[ ! -z "$all" ] && patch="-a"

# Treat "guilt pop" as "guilt pop -n 1".
if [ -z "$patch" ]; then
	patch=1
	num=t
fi

if [ ! -s "$applied" ]; then
	disp "No patches applied."
	if [ "$patch" = "-a" ]; then
		exit 0
	else
		exit 1
	fi
elif [ "$patch" = "-a" ]; then
	# we are supposed to pop all patches

	sidx=`wc -l < "$applied"`
	eidx=0
elif [ ! -z "$num" ]; then
	# we are supposed to pop a set number of patches

	[ "$patch" -lt 0 ] && die "Invalid number of patches to pop."

	sidx=`wc -l < "$applied"`
	eidx=`expr $sidx - $patch`

	# catch underflow
	[ $eidx -lt 0 ] && eidx=0
	[ $eidx -eq $sidx ] && die "No patches requested to be removed."
else
	# we're supposed to pop only up to a patch, make sure the patch is
	# in the series

	eidx=`cat "$applied" | grep -ne "^$patch$" | cut -d: -f 1`
	if [ -z "$eidx" ]; then
		die "Patch $patch is not in the series/is not applied"
	fi

	eidx=`expr $eidx - 1`
	sidx=`wc -l < "$applied"`
fi

# make sure that there are no unapplied changes
# if we are forcing the pop, reset first
if [ ! -z "$force" ]; then
	git reset --hard
elif ! must_commit_first; then
	die "Uncommited changes detected. Refresh first."
fi

l=`awk "BEGIN{n=0}(n==$eidx){print \\$0; exit}{n=n+1}END{}" < "$applied"`

pop_many_patches `git rev-parse refs/patches/$branch/$l^` `expr $sidx - $eidx`

p=`get_top`
[ ! -z "$p" ] && disp "Now at $p." || disp "All patches popped."

}