user-manual: document git-show-branch example
[git/dscho.git] / git-revert.sh
blob71cbcbc2b886b2770c61c4b3a496db913ef56d9d
1 #!/bin/sh
3 # Copyright (c) 2005 Linus Torvalds
4 # Copyright (c) 2005 Junio C Hamano
7 case "$0" in
8 *-revert* )
9 test -t 0 && edit=-e
10 replay=
11 me=revert
12 USAGE='[--edit | --no-edit] [-n] <commit-ish>' ;;
13 *-cherry-pick* )
14 replay=t
15 edit=
16 me=cherry-pick
17 USAGE='[--edit] [-n] [-r] [-x] <commit-ish>' ;;
18 * )
19 echo >&2 "What are you talking about?"
20 exit 1 ;;
21 esac
23 SUBDIRECTORY_OK=Yes ;# we will cd up
24 . git-sh-setup
25 require_work_tree
26 cd_to_toplevel
28 no_commit=
29 while case "$#" in 0) break ;; esac
31 case "$1" in
32 -n|--n|--no|--no-|--no-c|--no-co|--no-com|--no-comm|\
33 --no-commi|--no-commit)
34 no_commit=t
36 -e|--e|--ed|--edi|--edit)
37 edit=-e
39 --n|--no|--no-|--no-e|--no-ed|--no-edi|--no-edit)
40 edit=
42 -r)
43 : no-op ;;
44 -x|--i-really-want-to-expose-my-private-commit-object-name)
45 replay=
47 -*)
48 usage
51 break
53 esac
54 shift
55 done
57 test "$me,$replay" = "revert,t" && usage
59 case "$no_commit" in
61 # We do not intend to commit immediately. We just want to
62 # merge the differences in.
63 head=$(git-write-tree) ||
64 die "Your index file is unmerged."
67 head=$(git-rev-parse --verify HEAD) ||
68 die "You do not have a valid HEAD"
69 files=$(git-diff-index --cached --name-only $head) || exit
70 if [ "$files" ]; then
71 die "Dirty index: cannot $me (dirty: $files)"
74 esac
76 rev=$(git-rev-parse --verify "$@") &&
77 commit=$(git-rev-parse --verify "$rev^0") ||
78 die "Not a single commit $@"
79 prev=$(git-rev-parse --verify "$commit^1" 2>/dev/null) ||
80 die "Cannot run $me a root commit"
81 git-rev-parse --verify "$commit^2" >/dev/null 2>&1 &&
82 die "Cannot run $me a multi-parent commit."
84 encoding=$(git repo-config i18n.commitencoding || echo UTF-8)
86 # "commit" is an existing commit. We would want to apply
87 # the difference it introduces since its first parent "prev"
88 # on top of the current HEAD if we are cherry-pick. Or the
89 # reverse of it if we are revert.
91 case "$me" in
92 revert)
93 git show -s --pretty=oneline --encoding="$encoding" $commit |
94 sed -e '
95 s/^[^ ]* /Revert "/
96 s/$/"/
98 echo
99 echo "This reverts commit $commit."
100 test "$rev" = "$commit" ||
101 echo "(original 'git revert' arguments: $@)"
102 base=$commit next=$prev
105 cherry-pick)
106 pick_author_script='
107 /^author /{
108 s/'\''/'\''\\'\'\''/g
110 s/^author \([^<]*\) <[^>]*> .*$/\1/
111 s/'\''/'\''\'\'\''/g
112 s/.*/GIT_AUTHOR_NAME='\''&'\''/p
115 s/^author [^<]* <\([^>]*\)> .*$/\1/
116 s/'\''/'\''\'\'\''/g
117 s/.*/GIT_AUTHOR_EMAIL='\''&'\''/p
120 s/^author [^<]* <[^>]*> \(.*\)$/\1/
121 s/'\''/'\''\'\'\''/g
122 s/.*/GIT_AUTHOR_DATE='\''&'\''/p
127 logmsg=`git show -s --pretty=raw --encoding="$encoding" "$commit"`
128 set_author_env=`echo "$logmsg" |
129 LANG=C LC_ALL=C sed -ne "$pick_author_script"`
130 eval "$set_author_env"
131 export GIT_AUTHOR_NAME
132 export GIT_AUTHOR_EMAIL
133 export GIT_AUTHOR_DATE
135 echo "$logmsg" |
136 sed -e '1,/^$/d' -e 's/^ //'
137 case "$replay" in
139 echo "(cherry picked from commit $commit)"
140 test "$rev" = "$commit" ||
141 echo "(original 'git cherry-pick' arguments: $@)"
143 esac
144 base=$prev next=$commit
147 esac >.msg
149 # This three way merge is an interesting one. We are at
150 # $head, and would want to apply the change between $commit
151 # and $prev on top of us (when reverting), or the change between
152 # $prev and $commit on top of us (when cherry-picking or replaying).
154 echo >&2 "First trying simple merge strategy to $me."
155 git-read-tree -m -u --aggressive $base $head $next &&
156 result=$(git-write-tree 2>/dev/null) || {
157 echo >&2 "Simple $me fails; trying Automatic $me."
158 git-merge-index -o git-merge-one-file -a || {
159 mv -f .msg "$GIT_DIR/MERGE_MSG"
161 echo '
162 Conflicts:
164 git ls-files --unmerged |
165 sed -e 's/^[^ ]* / /' |
166 uniq
167 } >>"$GIT_DIR/MERGE_MSG"
168 echo >&2 "Automatic $me failed. After resolving the conflicts,"
169 echo >&2 "mark the corrected paths with 'git-add <paths>'"
170 echo >&2 "and commit the result."
171 case "$me" in
172 cherry-pick)
173 echo >&2 "You may choose to use the following when making"
174 echo >&2 "the commit:"
175 echo >&2 "$set_author_env"
176 esac
177 exit 1
179 result=$(git-write-tree) || exit
181 echo >&2 "Finished one $me."
183 # If we are cherry-pick, and if the merge did not result in
184 # hand-editing, we will hit this commit and inherit the original
185 # author date and name.
186 # If we are revert, or if our cherry-pick results in a hand merge,
187 # we had better say that the current user is responsible for that.
189 case "$no_commit" in
191 git-commit -n -F .msg $edit
192 rm -f .msg
194 esac