git-checkout-script

   1 #!/bin/sh
   2 : ${GIT_DIR=.git}
   3 old=$(git-rev-parse HEAD)
   4 new=
   5 force=
   6 branch=
   7 while [ "$#" != "0" ]; do
   8     arg="$1"
   9     shift
  10     case "$arg" in
  11         "-f")
  12                 force=1
  13                 ;;
  14         *)
  15                 rev=$(git-rev-parse --verify --revs-only "$arg")
  16                 if [ -z "$rev" ]; then
  17                         echo "unknown flag $arg"
  18                         exit 1
  19                 fi
  20                 if [ "$new" ]; then
  21                         echo "Multiple revisions?"
  22                         exit 1
  23                 fi
  24                 new="$rev"
  25                 if [ -f "$GIT_DIR/refs/heads/$arg" ]; then
  26                         branch="$arg"
  27                 fi
  28                 ;;
  29     esac
  30     i=$(($i+1))
  31 done
  32 [ -z "$new" ] && new=$old
  33
  34 if [ "$force" ]
  35 then
  36     git-read-tree --reset $new &&
  37         git-checkout-cache -q -f -u -a
  38 else
  39     git-read-tree -m -u $old $new
  40 fi
  41
  42 #
  43 # Switch the HEAD pointer to the new branch if it we
  44 # checked out a branch head, and remove any potential
  45 # old MERGE_HEAD's (subsequent commits will clearly not
  46 # be based on them, since we re-set the index)
  47 #
  48 if [ "$?" -eq 0 ]; then
  49         [ "$branch" ] && ln -sf "refs/heads/$branch" "$GIT_DIR/HEAD"
  50         rm -f "$GIT_DIR/MERGE_HEAD"
  51 fi