git-revert.sh

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