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         check_clean_tree || die "Cannot run $me from a dirty tree."
  60         head=$(git-rev-parse --verify HEAD) ||
  61                 die "You do not have a valid HEAD"
  62         ;;
  63 esac
  64
  65 rev=$(git-rev-parse --verify "$@") &&
  66 commit=$(git-rev-parse --verify "$rev^0") ||
  67         die "Not a single commit $@"
  68 prev=$(git-rev-parse --verify "$commit^1" 2>/dev/null) ||
  69         die "Cannot run $me a root commit"
  70 git-rev-parse --verify "$commit^2" >/dev/null 2>&1 &&
  71         die "Cannot run $me a multi-parent commit."
  72
  73 # "commit" is an existing commit.  We would want to apply
  74 # the difference it introduces since its first parent "prev"
  75 # on top of the current HEAD if we are cherry-pick.  Or the
  76 # reverse of it if we are revert.
  77
  78 case "$me" in
  79 revert)
  80         git-rev-list --pretty=oneline --max-count=1 $commit |
  81         sed -e '
  82                 s/^[^ ]* /Revert "/
  83                 s/$/"/'
  84         echo
  85         echo "This reverts $commit commit."
  86         test "$rev" = "$commit" ||
  87         echo "(original 'git revert' arguments: $@)"
  88         base=$commit next=$prev
  89         ;;
  90
  91 cherry-pick)
  92         pick_author_script='
  93         /^author /{
  94                 h
  95                 s/^author \([^<]*\) <[^>]*> .*$/\1/
  96                 s/'\''/'\''\'\'\''/g
  97                 s/.*/GIT_AUTHOR_NAME='\''&'\''/p
  98
  99                 g
 100                 s/^author [^<]* <\([^>]*\)> .*$/\1/
 101                 s/'\''/'\''\'\'\''/g
 102                 s/.*/GIT_AUTHOR_EMAIL='\''&'\''/p
 103
 104                 g
 105                 s/^author [^<]* <[^>]*> \(.*\)$/\1/
 106                 s/'\''/'\''\'\'\''/g
 107                 s/.*/GIT_AUTHOR_DATE='\''&'\''/p
 108
 109                 q
 110         }'
 111         set_author_env=`git-cat-file commit "$commit" |
 112         sed -ne "$pick_author_script"`
 113         eval "$set_author_env"
 114         export GIT_AUTHOR_NAME
 115         export GIT_AUTHOR_EMAIL
 116         export GIT_AUTHOR_DATE
 117
 118         git-cat-file commit $commit | sed -e '1,/^$/d'
 119         case "$replay" in
 120         '')
 121                 echo "(cherry picked from $commit commit)"
 122                 test "$rev" = "$commit" ||
 123                 echo "(original 'git cherry-pick' arguments: $@)"
 124                 ;;
 125         esac
 126         base=$prev next=$commit
 127         ;;
 128
 129 esac >.msg
 130
 131 # This three way merge is an interesting one.  We are at
 132 # $head, and would want to apply the change between $commit
 133 # and $prev on top of us (when reverting), or the change between
 134 # $prev and $commit on top of us (when cherry-picking or replaying).
 135
 136 echo >&2 "First trying simple merge strategy to $me."
 137 git-read-tree -m -u $base $head $next &&
 138 result=$(git-write-tree 2>/dev/null) || {
 139     echo >&2 "Simple $me fails; trying Automatic $me."
 140     git-merge-index -o git-merge-one-file -a || {
 141             echo >&2 "Automatic $me failed.  After fixing it up,"
 142             echo >&2 "you can use \"git commit -F .msg\""
 143             case "$me" in
 144             cherry-pick)
 145                 echo >&2 "You may choose to use the following when making"
 146                 echo >&2 "the commit:"
 147                 echo >&2 "$set_author_env"
 148             esac
 149             exit 1
 150     }
 151     result=$(git-write-tree) || exit
 152 }
 153 echo >&2 "Finished one $me."
 154
 155 # If we are cherry-pick, and if the merge did not result in
 156 # hand-editing, we will hit this commit and inherit the original
 157 # author date and name.
 158 # If we are revert, or if our cherry-pick results in a hand merge,
 159 # we had better say that the current user is responsible for that.
 160
 161 case "$no_commit" in
 162 '')
 163         git-commit -n -F .msg
 164         rm -f .msg
 165         ;;
 166 esac