rerere: add clear, diff, and status commands

diff --git a/git-checkout.sh b/git-checkout.sh
index 5613bfc403f7a4208d2a85de73ec33229e5a3f10..737abd0c094ae6cfb201fb46c28f4962a9826a02 100755 (executable)
--- a/git-checkout.sh
+++ b/git-checkout.sh
@@ -4,8 +4,8 @@ USAGE='[-f] [-b <new_branch>] [-m] [<branch>] [<paths>...]'
 SUBDIRECTORY_OK=Sometimes
 . git-sh-setup
 
-old=$(git-rev-parse HEAD)
 old_name=HEAD
+old=$(git-rev-parse --verify $old_name 2>/dev/null)
 new=
 new_name=
 force=
@@ -22,7 +22,7 @@ while [ "$#" != "0" ]; do
                shift
                [ -z "$newbranch" ] &&
                        die "git checkout: -b needs a branch name"
-               [ -e "$GIT_DIR/refs/heads/$newbranch" ] &&
+               git-show-ref --verify --quiet -- "refs/heads/$newbranch" &&
                        die "git checkout: branch $newbranch already exists"
                git-check-ref-format "heads/$newbranch" ||
                        die "git checkout: we do not like '$newbranch' as a branch name."
@@ -51,7 +51,8 @@ while [ "$#" != "0" ]; do
                        fi
                        new="$rev"
                        new_name="$arg^0"
-                       if [ -f "$GIT_DIR/refs/heads/$arg" ]; then
+                       if git-show-ref --verify --quiet -- "refs/heads/$arg"
+                       then
                                branch="$arg"
                        fi
                elif rev=$(git-rev-parse --verify "$arg^{tree}" 2>/dev/null)
@@ -67,11 +68,20 @@ while [ "$#" != "0" ]; do
                        set x "$arg" "$@"
                        shift
                fi
+               case "$1" in
+               --)
+                       shift ;;
+               esac
                break
                ;;
     esac
 done
 
+case "$force$merge" in
+11)
+       die "git checkout: -f and -m are incompatible"
+esac
+
 # The behaviour of the command with and without explicit path
 # parameters is quite different.
 #
@@ -102,7 +112,11 @@ Did you intend to checkout '$@' which can not be resolved as commit?"
                git-ls-tree --full-name -r "$new" "$@" |
                git-update-index --index-info || exit $?
        fi
-       git-checkout-index -f -u -- "$@"
+
+       # Make sure the request is about existing paths.
+       git-ls-files --error-unmatch -- "$@" >/dev/null || exit
+       git-ls-files -- "$@" |
+       git-checkout-index -f -u --stdin
        exit $?
 else
        # Make sure we did not fall back on $arg^{tree} codepath
@@ -135,6 +149,13 @@ fi
        die "git checkout: to checkout the requested commit you need to specify 
               a name for a new branch which is created and switched to"
 
+if [ "X$old" = X ]
+then
+       echo "warning: You do not appear to currently be on a branch." >&2
+       echo "warning: Forcing checkout of $new_name." >&2
+       force=1
+fi
+
 if [ "$force" ]
 then
     git-read-tree --reset -u $new