git-revert.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Linus Torvalds
   4 # Copyright (c) 2005 Junio C Hamano
   5 #
   6
   7 case "$0" in
   8 *-revert* )
   9         test -t 0 && edit=-e
  10         replay=
  11         me=revert
  12         USAGE='[--edit | --no-edit] [-n] <commit-ish>' ;;
  13 *-cherry-pick* )
  14         replay=t
  15         edit=
  16         me=cherry-pick
  17         USAGE='[--edit] [-n] [-r] [-x] <commit-ish>'  ;;
  18 * )
  19         die "What are you talking about?" ;;
  20 esac
  21 . git-sh-setup
  22
  23 no_commit=
  24 while case "$#" in 0) break ;; esac
  25 do
  26         case "$1" in
  27         -n|--n|--no|--no-|--no-c|--no-co|--no-com|--no-comm|\
  28             --no-commi|--no-commit)
  29                 no_commit=t
  30                 ;;
  31         -e|--e|--ed|--edi|--edit)
  32                 edit=-e
  33                 ;;
  34         --n|--no|--no-|--no-e|--no-ed|--no-edi|--no-edit)
  35                 edit=
  36                 ;;
  37         -r)
  38                 : no-op ;;
  39         -x|--i-really-want-to-expose-my-private-commit-object-name)
  40                 replay=
  41                 ;;
  42         -*)
  43                 usage
  44                 ;;
  45         *)
  46                 break
  47                 ;;
  48         esac
  49         shift
  50 done
  51
  52 test "$me,$replay" = "revert,t" && usage
  53
  54 case "$no_commit" in
  55 t)
  56         # We do not intend to commit immediately.  We just want to
  57         # merge the differences in.
  58         head=$(git-write-tree) ||
  59                 die "Your index file is unmerged."
  60         ;;
  61 *)
  62         head=$(git-rev-parse --verify HEAD) ||
  63                 die "You do not have a valid HEAD"
  64         files=$(git-diff-index --cached --name-only $head) || exit
  65         if [ "$files" ]; then
  66                 die "Dirty index: cannot $me (dirty: $files)"
  67         fi
  68         ;;
  69 esac
  70
  71 rev=$(git-rev-parse --verify "$@") &&
  72 commit=$(git-rev-parse --verify "$rev^0") ||
  73         die "Not a single commit $@"
  74 prev=$(git-rev-parse --verify "$commit^1" 2>/dev/null) ||
  75         die "Cannot run $me a root commit"
  76 git-rev-parse --verify "$commit^2" >/dev/null 2>&1 &&
  77         die "Cannot run $me a multi-parent commit."
  78
  79 # "commit" is an existing commit.  We would want to apply
  80 # the difference it introduces since its first parent "prev"
  81 # on top of the current HEAD if we are cherry-pick.  Or the
  82 # reverse of it if we are revert.
  83
  84 case "$me" in
  85 revert)
  86         git-rev-list --pretty=oneline --max-count=1 $commit |
  87         sed -e '
  88                 s/^[^ ]* /Revert "/
  89                 s/$/"/'
  90         echo
  91         echo "This reverts commit $commit."
  92         test "$rev" = "$commit" ||
  93         echo "(original 'git revert' arguments: $@)"
  94         base=$commit next=$prev
  95         ;;
  96
  97 cherry-pick)
  98         pick_author_script='
  99         /^author /{
 100                 s/'\''/'\''\\'\'\''/g
 101                 h
 102                 s/^author \([^<]*\) <[^>]*> .*$/\1/
 103                 s/'\''/'\''\'\'\''/g
 104                 s/.*/GIT_AUTHOR_NAME='\''&'\''/p
 105
 106                 g
 107                 s/^author [^<]* <\([^>]*\)> .*$/\1/
 108                 s/'\''/'\''\'\'\''/g
 109                 s/.*/GIT_AUTHOR_EMAIL='\''&'\''/p
 110
 111                 g
 112                 s/^author [^<]* <[^>]*> \(.*\)$/\1/
 113                 s/'\''/'\''\'\'\''/g
 114                 s/.*/GIT_AUTHOR_DATE='\''&'\''/p
 115
 116                 q
 117         }'
 118         set_author_env=`git-cat-file commit "$commit" |
 119         LANG=C LC_ALL=C sed -ne "$pick_author_script"`
 120         eval "$set_author_env"
 121         export GIT_AUTHOR_NAME
 122         export GIT_AUTHOR_EMAIL
 123         export GIT_AUTHOR_DATE
 124
 125         git-cat-file commit $commit | sed -e '1,/^$/d'
 126         case "$replay" in
 127         '')
 128                 echo "(cherry picked from commit $commit)"
 129                 test "$rev" = "$commit" ||
 130                 echo "(original 'git cherry-pick' arguments: $@)"
 131                 ;;
 132         esac
 133         base=$prev next=$commit
 134         ;;
 135
 136 esac >.msg
 137
 138 # This three way merge is an interesting one.  We are at
 139 # $head, and would want to apply the change between $commit
 140 # and $prev on top of us (when reverting), or the change between
 141 # $prev and $commit on top of us (when cherry-picking or replaying).
 142
 143 echo >&2 "First trying simple merge strategy to $me."
 144 git-read-tree -m -u --aggressive $base $head $next &&
 145 result=$(git-write-tree 2>/dev/null) || {
 146     echo >&2 "Simple $me fails; trying Automatic $me."
 147     git-merge-index -o git-merge-one-file -a || {
 148             echo >&2 "Automatic $me failed.  After resolving the conflicts,"
 149             echo >&2 "mark the corrected paths with 'git-update-index <paths>'"
 150             echo >&2 "and commit with 'git commit -F .msg'"
 151             case "$me" in
 152             cherry-pick)
 153                 echo >&2 "You may choose to use the following when making"
 154                 echo >&2 "the commit:"
 155                 echo >&2 "$set_author_env"
 156             esac
 157             exit 1
 158     }
 159     result=$(git-write-tree) || exit
 160 }
 161 echo >&2 "Finished one $me."
 162
 163 # If we are cherry-pick, and if the merge did not result in
 164 # hand-editing, we will hit this commit and inherit the original
 165 # author date and name.
 166 # If we are revert, or if our cherry-pick results in a hand merge,
 167 # we had better say that the current user is responsible for that.
 168
 169 case "$no_commit" in
 170 '')
 171         git-commit -n -F .msg $edit
 172         rm -f .msg
 173         ;;
 174 esac