Rust/cargo dependencies

Hello,

I am attempting to update security/py-bcyrpt to 4.1.2, however, the Port
now requires much oxidisation, and I am completely lost on how to apply
that. If I add cargo to ${USES}, then makesum and cargo-crates both
overwrite distinfo, removing the distfile information for py-bcrypt.
poudriere-testport will not complete because the build wants to update
some index via crates.io, and network access is restricted during
testport. I have had to set ${CARGO_CARGOTOML}, however, that only works
when ${USES} is not populated with cargo. How does one configure the
Port so ${WRKSRC} stopped getting nuked and replaced with cargo-crates,
and how can testport continue without network access?

--
To health and anarchy
Alastair