aboutsummaryrefslogtreecommitdiff
path: root/git-revert.sh
blob: 2c5870684c9a0993116a86a511a0e9998a27b621 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
#!/bin/sh
#
# Copyright (c) 2005 Linus Torvalds
# Copyright (c) 2005 Junio C Hamano
#

case "$0" in
*-revert* )
	test -t 0 && edit=-e
	me=revert
	USAGE='[--edit | --no-edit] [-n] <commit-ish>' ;;
*-cherry-pick* )
	edit=
	me=cherry-pick
	USAGE='[--edit] [-n] [-r] <commit-ish>'  ;;
* )
	die "What are you talking about?" ;;
esac
. git-sh-setup

no_commit= replay=
while case "$#" in 0) break ;; esac
do
	case "$1" in
	-n|--n|--no|--no-|--no-c|--no-co|--no-com|--no-comm|\
	    --no-commi|--no-commit)
		no_commit=t
		;;
	-e|--e|--ed|--edi|--edit)
		edit=-e
		;;
	--n|--no|--no-|--no-e|--no-ed|--no-edi|--no-edit)
		edit=
		;;
	-r|--r|--re|--rep|--repl|--repla|--replay)
		replay=t
		;;
	-*)
		usage
		;;
	*)
		break
		;;
	esac
	shift
done

test "$me,$replay" = "revert,t" && usage

case "$no_commit" in
t)
	# We do not intend to commit immediately.  We just want to
	# merge the differences in.
	head=$(git-write-tree) ||
		die "Your index file is unmerged."
	;;
*)
	head=$(git-rev-parse --verify HEAD) ||
		die "You do not have a valid HEAD"
	files=$(git-diff-index --cached --name-only $head) || exit
	if [ "$files" ]; then
		die "Dirty index: cannot $me (dirty: $files)"
	fi
	;;
esac

rev=$(git-rev-parse --verify "$@") &&
commit=$(git-rev-parse --verify "$rev^0") ||
	die "Not a single commit $@"
prev=$(git-rev-parse --verify "$commit^1" 2>/dev/null) ||
	die "Cannot run $me a root commit"
git-rev-parse --verify "$commit^2" >/dev/null 2>&1 &&
	die "Cannot run $me a multi-parent commit."

# "commit" is an existing commit.  We would want to apply
# the difference it introduces since its first parent "prev"
# on top of the current HEAD if we are cherry-pick.  Or the
# reverse of it if we are revert.

case "$me" in
revert)
	git-rev-list --pretty=oneline --max-count=1 $commit |
	sed -e '
		s/^[^ ]* /Revert "/
		s/$/"/'
	echo
	echo "This reverts $commit commit."
	test "$rev" = "$commit" ||
	echo "(original 'git revert' arguments: $@)"
	base=$commit next=$prev
	;;

cherry-pick)
	pick_author_script='
	/^author /{
		s/'\''/'\''\\'\'\''/g
		h
		s/^author \([^<]*\) <[^>]*> .*$/\1/
		s/'\''/'\''\'\'\''/g
		s/.*/GIT_AUTHOR_NAME='\''&'\''/p

		g
		s/^author [^<]* <\([^>]*\)> .*$/\1/
		s/'\''/'\''\'\'\''/g
		s/.*/GIT_AUTHOR_EMAIL='\''&'\''/p

		g
		s/^author [^<]* <[^>]*> \(.*\)$/\1/
		s/'\''/'\''\'\'\''/g
		s/.*/GIT_AUTHOR_DATE='\''&'\''/p

		q
	}'
	set_author_env=`git-cat-file commit "$commit" |
	LANG=C LC_ALL=C sed -ne "$pick_author_script"`
	eval "$set_author_env"
	export GIT_AUTHOR_NAME
	export GIT_AUTHOR_EMAIL
	export GIT_AUTHOR_DATE

	git-cat-file commit $commit | sed -e '1,/^$/d'
	case "$replay" in
	'')
		echo "(cherry picked from $commit commit)"
		test "$rev" = "$commit" ||
		echo "(original 'git cherry-pick' arguments: $@)"
		;;
	esac
	base=$prev next=$commit
	;;

esac >.msg

# This three way merge is an interesting one.  We are at
# $head, and would want to apply the change between $commit
# and $prev on top of us (when reverting), or the change between
# $prev and $commit on top of us (when cherry-picking or replaying).

echo >&2 "First trying simple merge strategy to $me."
git-read-tree -m -u $base $head $next &&
result=$(git-write-tree 2>/dev/null) || {
    echo >&2 "Simple $me fails; trying Automatic $me."
    git-merge-index -o git-merge-one-file -a || {
	    echo >&2 "Automatic $me failed.  After fixing it up,"
	    echo >&2 "you can use \"git commit -F .msg\""
	    case "$me" in
	    cherry-pick)
		echo >&2 "You may choose to use the following when making"
		echo >&2 "the commit:"
		echo >&2 "$set_author_env"
	    esac
	    exit 1
    }
    result=$(git-write-tree) || exit
}
echo >&2 "Finished one $me."

# If we are cherry-pick, and if the merge did not result in
# hand-editing, we will hit this commit and inherit the original
# author date and name.
# If we are revert, or if our cherry-pick results in a hand merge,
# we had better say that the current user is responsible for that.

case "$no_commit" in
'')
	git-commit -n -F .msg $edit
	rm -f .msg
	;;
esac