sql/json miscellaneous issue

hi.
the following two queries should return the same result?

SELECT * FROM JSON_query (jsonb 'null', '$' returning jsonb);
SELECT * FROM JSON_value (jsonb 'null', '$' returning jsonb);

I've tried a patch to implement it.
(i raised the issue at
https://www.postgresql.org/message-id/CACJufxFWiCnG3Q7f0m_GdrytPbv29A5OWngCDwKVjcftwzHbTA%40mail.gmail.com
i think a new thread would be more appropriate).



current json_value  doc:
"Note that scalar strings returned by json_value always have their
quotes removed, equivalent to specifying OMIT QUOTES in json_query."

i think there are two exceptions: when the returning data types are
jsonb or json.