On Wed, 2024-08-07 at 19:39 +0200, Michał Górny wrote:
> On Wed, 2024-08-07 at 16:52 +0100, James Le Cuirot wrote:
> > The flags we set an a target-specific environment variable override any
> > generic [build] flags set by the project, requiring ebuilds to set these
> > themselves, which is undesirable. Work around this by using tomlq to
> > read the flags from the config files checked by Cargo and prepending
> > them to our environment variable.
> > 
> > Signed-off-by: James Le Cuirot <chewi@gentoo.org>
> > ---
> >  eclass/cargo.eclass | 28 +++++++++++++++++-----------
> >  1 file changed, 17 insertions(+), 11 deletions(-)
> > 
> > diff --git a/eclass/cargo.eclass b/eclass/cargo.eclass
> > index 6d4cf1b425eb..dea8c49e4585 100644
> > --- a/eclass/cargo.eclass
> > +++ b/eclass/cargo.eclass
> > @@ -36,7 +36,8 @@ esac
> >  
> >  inherit flag-o-matic multiprocessing rust-toolchain toolchain-funcs
> >  
> > -[[ ! ${CARGO_OPTIONAL} ]] && BDEPEND="${RUST_DEPEND}"
> > +# app-misc/yq is needed for tomlq.
> > +[[ ! ${CARGO_OPTIONAL} ]] && BDEPEND="${RUST_DEPEND} app-misc/yq"
> >  
> 
> Doesn't this imply that all ebuilds using CARGO_OPTIONAL will now have
> to explicitly depend on yq?

Good catch, thanks. I can update the eclass docs accordingly. I count 23
ebuilds across 8 packages, and this can be done without a revbump, so it's not
too bad. Even if it were missing, it would just continue without applying
these extra flags.

I have also noticed that yq will need some keywording first.

I considered some inline Python with just tomli instead, but then you get into
the mess of micro-managing the Python versions. I don't think there's a way to
say "use whatever Python tomli is installed for".