On Mon, Mar 09, 2020 at 10:26:01AM +0100, Hartmut Goebel wrote:
> Am 08.03.20 um 21:10 schrieb John Soo:
> > Hmm. Can you elaborate more on “not able to build non-trivial rust applications”?
> 
> I'm working on packaging sequoia-openpgp.org.
> 
> This requires nettle-sys, a FFI to nettle. nettly-sys "optionally"
> requires "nettle-src". I added a phase to "nettle-sys" to remove the
> "optional" dependency. nettle-sys also requires bindgen.

As I assume you saw, there is nothing "optional" when using the
cargo-build-system. For nettle-sys and nettle-src I suggest looking at
rust-openssl-sys-no-vendor.patch which I modified from Debian. It takes
care of pretending openssl-sys also provides openssl-src.

> A second dependancy is "sequoia-openpgp", which requires rhe lalrpop
> parser generator for building.
> 
> Now when building `sequioa-sqv`, I need to add all these dependencies again:
> 
> - nettle-src, since it is "optional" for nettle-sys - and the phase was
> not executed.
> - bindgen, since it is required to build nettle-sys
> - lalrpop, since it is required for building sequoia-openpgp
> 
> > Patching a library Cargo.toml seems like an excellent job for source patches or snippets.
> 
> Quite some packages change Cargo.toml in a phase, e.g. rust-openssl-0.7.
> Thus I assumed, this is the way to go.

That could probably move to a snippet, or even into the
cargo-build-system. IIRC there are only 3 patterns like that which
appear multiple times, and they're only relevant when building that
actual crate, not when it's "just a dependency".

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Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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