refactor

we don't need to extract the -nickname option since when the same
option is specified more than once, the last value wins

weave

@@ -684,7 +684,6 @@ case "$COMMAND" in
             echo "WARNING: $1 parameter ignored; 'weave launch' no longer takes a CIDR as the first parameter" >&2
             shift 1
         fi
-        NICKNAME=$(hostname)
         CONTAINER_PORT=$PORT
         while true; do
             case "$1" in
@@ -694,11 +693,6 @@ case "$COMMAND" in
                     export WEAVE_PASSWORD
                     shift 2
                     ;;
-                -nickname)
-                    [ $# -gt 1 ] || usage
-                    NICKNAME="$2"
-                    shift 2
-                    ;;
                 -port)
                     [ $# -gt 1 ] || usage
                     CONTAINER_PORT="$2"
@@ -714,7 +708,7 @@ case "$COMMAND" in
         # when launching the weave container.
         CONTAINER=$(docker run --privileged -d --name=$CONTAINER_NAME \
             -p $PORT:$CONTAINER_PORT/tcp -p $PORT:$CONTAINER_PORT/udp -e WEAVE_PASSWORD \
-            $WEAVE_DOCKER_ARGS $IMAGE -iface $CONTAINER_IFNAME -port $CONTAINER_PORT -name "$PEERNAME" -nickname "$NICKNAME" "$@")
+            $WEAVE_DOCKER_ARGS $IMAGE -iface $CONTAINER_IFNAME -port $CONTAINER_PORT -name "$PEERNAME" -nickname "$(hostname)" "$@")
         with_container_netns $CONTAINER launch >/dev/null
         wait_for_status $CONTAINER_NAME $HTTP_PORT
         echo $CONTAINER