[Pkg-rust-maintainers] debcargo bin packages FTBFS because they need dev-dependencies

[Josh Triplett]

On Mon, Jan 29, 2018 at 04:14:00AM +0000, Ximin Luo wrote:
> Ximin Luo:
> > [..] Should we just add dev-dependencies to Build-Depends in d/control? [..]
> 
> Another option is to patch cargo not to check those dependencies, see
> 
> https://github.com/rust-lang/cargo/issues/4988
> 
> however my patch is (had to be) quite invasive...

I just followed up to that issue. Cargo definitely should *not* require
dev-dependencies in `cargo install`.  This seems closely related to
https://github.com/rust-lang/cargo/pull/3369 , in which I fixed `cargo
install` to not require optional dependencies for non-enabled features.
I would suggest checking the same `require_optional_deps` flag and not
checking for dev-dependencies if false.

- Josh Triplett