- check functions are never called with a NULL args list, it is always
an array, so first check can be removed
- the expression parser guarantees that we can't have anything else,
because we mentioned json converter takes a mandatory string argument.
Thus test on `ARGT_STR` can be removed as well
- also add breaking line between enum and function declaration
In order to validate it, add a simple json test testing very simple
cases but can be improved in the future:
- default json converter without args
- json converter failing on error (utf8)
- json converter with error being removed (utf8s)
Signed-off-by: William Dauchy <wdauchy@gmail.com>
