[Pkg-rust-maintainers] Bug#860116: RFH: cargo -- Rust package manager

[Ximin Luo]

Package: wnpp
Severity: normal

We request assistance with maintaining the cargo package, as well as Rust
packaging in general.

Firefox's next versions[1] will require rust, but the Debian pkg-rust team is
severely short on time to maintain these packages.

sylvestre@ and I are just about managing to keep rustc in Debian up-to-date
in our spare time.

lucab@ and gus@ know more about the rust ecosystem than either of us, but they
have not been very active recently. lucab@ had been maintaining cargo.

Right now, cargo needs to be updated to the next version, there are some open
bugs about it:

https://bugs.debian.org/cgi-bin/pkgreport.cgi?src=cargo

I have not yet looked at this package myself but if there are any questions you
can probably prod lucab@ to answer them. He has a different handle on IRC, you
can join #debian-rust on OFTC to talk to us.

After this, we will need to update rustc to 1.16.0. This is packaged in git,
and it works (doko@ has already uploaded it to Ubuntu) however it uses some
deprecated Makefiles which are to be removed in the next 1.17.0 release.
Therefore, we should try to upload 1.16.0 using the new "rustbuild" buildsystem
which also build-depends on cargo. (To try this out, remove --disable-rustbuild
from d/rules.)

After that, we will have to figure out how to cross-compile cargo and rust
for other architectures. So far, we have been bootstrapping rustc on other
arches by using upstream's binary blobs, but this is not the ideal approach,
and will become even harder once we have the rustc<->cargo cyclic build
dependency. Upstream themselves prefer the cross-compilation approach, and had
previously given me some tips that I need to go dig out again from my IRC logs.

At some point we should also start packaging actual rust packages. Josh
Triplett had been planning to automate a large part of this, the work is still
incomplete but we have a Rust Packaging policy already:

https://wiki.debian.org/Teams/RustPackaging/Policy

Package automation tools:

https://anonscm.debian.org/cgit/pkg-rust/dh-cargo.git (low-level dh glue)
https://crates.io/crates/debcargo (high-level automater)

[1] https://buildd.debian.org/status/package.php?p=firefox&suite=experimental