Create a proper eclass for crates

[suhr]

Prototype: https://github.com/suhr/badumz/blob/master/eclass/cargo-utils.eclass
Also relevant: https://github.com/gentoo/gentoo/blob/master/eclass/cargo.eclass

Unresolved questions:

• Should we download sources somewhere to distfiles
• How to combine cargo fetch with other unpacks (git, archives)

cast @cardoe

[cardoe]

I'm working towards this. I'm actually tackling this on Yocto first. You can see an example recipe here: starlab-io/meta-rust@112d40a And you can see the rest of the commits here: https://github.com/starlab-io/meta-rust/commits/crate-fetch

Its not totally done yet. But the main tree eclass does fetch crates to distfiles as name-version.crate

[cardoe]

Oh and we can't use cargo fetch until Gentoo adds a src_fetch phase.

[cardoe]

What files does cargo install create? Does it generate additional metadata?

[suhr]

Great!

There's some problem though. Looks like it lists all dependencies in SRC_URI. But a list of all dependencies can be quite big, so ebuilds become hard to create and edit.

Does it generate additional metadata?

Yep, it creates $CARGO_HOME/.crates.toml. We don't need it because removing doesn't require cargo.

[cardoe]

I don't disagree that the dependencies become quite big. But the only way to get things in tree is that we need to let the package manager download the files until src_fetch() gets added in an EAPI.

I don't think ebuilds that build cargo packages should be made by hand. They should be made by a tool. see https://github.com/cardoe/cargo-ebuild that I'm working on to generate ebuilds.

You can see an example ebuild for rustfmt here: https://github.com/cardoe/gentoo/tree/rustfmt

[gentoo90]

Maybe local registries from rust-lang/cargo#2361 could be useful here

[cardoe]

@gentoo90 We're working on this in rust-lang/cargo#2857

[cardoe]

Now that we have the necessary versions in the tree, I took a swag at doing this. Please checkout https://github.com/cardoe/gentoo/tree/rustfmt

[cardoe]

Pretty sure I broke the build of cargo with this change so I'll have to work on it some more.

[cardoe]

Well rustfmt installs properly now. Now to sync up the ebuild with what I'm generating with https://github.com/cardoe/cargo-ebuild

[cardoe]

cargo-ebuild 0.1.2 should produce ebuilds for things published on crates.io that work with these changes.

[cardoe]

Alright. I believe everything is updated. @gentoo90 if you want to take a peek and tell me what you think of my branch? I didn't notice you had done the work already until this morning and could have probably saved myself some time using your changes.

[gibix]

this can be closed