Solution for Text values potentially containing '\NUL'

[googleson78]

Currently we allow encoding any Text value, including ones that contain '\NUL', via ToField.

This is a theoretical issue because PG actually doesn't allow strings to contain the 0 code point, meaning that we can end up having a valid Text value which is not actually storable in PG - described in the end of this section of the manual

It is also a practical issue because generating text via Arbitrary easily leads to Text with '\NUL\ in it, meaning that we can't use Arbitrary Text out of the box to run some property tests which do insertion into PG.

Is there some way to improve this situation?

There could potentially be a newtype wrapper over Text which only allows for Texts which don't contain '\NUL', but that still means users have to write their own Arbitrary, since (I assume) this library won't depend on QuickCheck and the like. This will at least solve the theoretical concern of trying to insert a Text with '\NUL' in it and seeing it fail, if the ordinary Text instance gets gradually phased out (which there's no easy way to do right now at the moment, afaik).