The following
#!/bin/sh
. /usr/share/libubox/jshn.sh
json_init
json_add_array array
json_add_string "" "item1"
json_add_string "" "item2"
json_add_string "" "item3"
json_close_array
json_add_array array
json_add_string "" "itemA"
json_add_string "" "itemB"
json_add_string "" "itemC"
json_close_array
json_dump
outputs
which is surprising. I've expected it to output
{ "array": [ "itemA", "itemB", "itemC" ] }