Fix pulling into the same branch.

diff --git a/git-fetch-script b/git-fetch-script
index b581dc4cd6fa7fe6406cf3b1e1e142118a52b00b..dd94edeb38eb47dc6abf5e00c1a5d8c067a76f74 100755 (executable)
--- a/git-fetch-script
+++ b/git-fetch-script
@@ -7,28 +7,33 @@ _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
 
 append=
 force=
+update_head_ok=
 while case "$#" in 0) break ;; esac
 do
        case "$1" in
        -a|--a|--ap|--app|--appe|--appen|--append)
                append=t
-               shift
                ;;
        -f|--f|--fo|--for|--forc|--force)
                force=t
-               shift
+               ;;
+       -u|--u|--up|--upd|--upda|--updat|--update|--update-|--update-h|\
+       --update-he|--update-hea|--update-head|--update-head-|\
+       --update-head-o|--update-head-ok)
+               update_head_ok=t
                ;;
        *)
                break
                ;;
        esac
+       shift
 done
 
 case "$#" in
 0)
        test -f "$GIT_DIR/branches/origin" ||
                test -f "$GIT_DIR/remotes/origin" ||
-                       die "Where do you want to fetch from?"
+                       die "Where do you want to fetch from today?"
        set origin ;;
 esac
 
@@ -124,6 +129,12 @@ fast_forward_local () {
     esac
 }
 
+case "$update_head_ok" in
+'')
+       orig_head=$(cat "$GIT_DIR/HEAD" 2>/dev/null)
+       ;;
+esac
+
 for ref in $(get_remote_refs_for_fetch "$@")
 do
     refs="$refs $ref"
@@ -150,7 +161,7 @@ do
        fi
        head=$(curl -nsf $curl_extra_args "$remote/$remote_name") &&
        expr "$head" : "$_x40\$" >/dev/null ||
-           die "Failed to fetch $remote_name from $remote"
+               die "Failed to fetch $remote_name from $remote"
        echo Fetching "$remote_name from $remote" using http
        git-http-pull -v -a "$head" "$remote/" || exit
        ;;
@@ -201,3 +212,18 @@ http://* | https://* | rsync://* )
     done
     ;;
 esac
+
+# If the original head was empty (i.e. no "master" yet), or
+# if we were told not to worry, we do not have to check.
+case ",$update_head_ok,$orig_head," in
+*,, | t,* )
+       ;;
+*)
+       curr_head=$(cat "$GIT_DIR/HEAD" 2>/dev/null)
+       if test "$curr_head" != "$orig_head"
+       then
+               echo "$orig_head" >$GIT_DIR/HEAD
+               die "Cannot fetch into the current branch."
+       fi
+       ;;
+esac