Build script complaining about cargo edition feature #99

  error: failed to parse manifest at` /workspace_root/shaders/Cargo.toml`

  Caused by:
    feature `edition2024` is required

    The package requires the Cargo feature called `edition2024`, but that feature is not stabilized in this version of Cargo (1.84.0-nightly (66221abde 2024-11-19)).
    Consider adding `cargo-features = ["edition2024"]` to the top of Cargo.toml (above the [package] table) to tell Cargo you are opting in to use this unstable feature.
    See https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#edition-2024 for more information about the status of this feature.
  Error: BuildFailed

use cargo_gpu::spirv_builder::{MetadataPrintout, SpirvMetadata};
use std::path::PathBuf;
use std::{env, fs};

// mostly stolen from https://github.com/Rust-GPU/rust-gpu/issues/291#issuecomment-3004833358

fn main() -> Result<(), Box<dyn std::error::Error>> {
	let target_arch = env::var("CARGO_CFG_TARGET_ARCH").expect("Always set by Cargo; qed");
	
	if target_arch != "spirv" {
		let out_dir = env::var("OUT_DIR").expect("Always set by Cargo; qed");
		
		// Skip compilation under Clippy, it doesn't work for some reason and isn't really needed
		// anyway
		if env::var("CLIPPY_ARGS").is_ok() {
			let empty_file = PathBuf::from(out_dir).join("empty.bin");
			fs::write(&empty_file, [])?;
			println!("cargo::rustc-env=SHADER_PATH={}", empty_file.display());
			
			return Ok(());
		}
		
		let profile = env::var("PROFILE").expect("Always set by Cargo; qed");
		
		let shader_crate = PathBuf::from("./shaders");
		
		// TODO: Workaround for https://github.com/Rust-GPU/cargo-gpu/issues/90
		let cargo_target_dir = env::var("CARGO_TARGET_DIR").ok();
		// SAFETY: Single-threaded
		unsafe {
			env::remove_var("CARGO_TARGET_DIR");
		}
		
		let backend = cargo_gpu::Install::from_shader_crate(shader_crate.clone()).run()?;

		// TODO: Workaround for https://github.com/Rust-GPU/cargo-gpu/issues/90
		if let Some(cargo_target_dir) = cargo_target_dir {
			// SAFETY: Single-threaded
			unsafe {
				env::set_var("CARGO_TARGET_DIR", cargo_target_dir);
			}
		}
		
		let mut builder = backend.to_spirv_builder(shader_crate, "spirv-unknown-vulkan1.2");
		builder.print_metadata = MetadataPrintout::DependencyOnly;
		builder.spirv_metadata = if profile == "debug" {
			SpirvMetadata::NameVariables
		} else {
			SpirvMetadata::None
		};
		// Avoid Cargo deadlock
		builder.target_dir_path.replace(out_dir.into());

		let spv_result = builder.build()?;
		
		let path_to_shaders = spv_result.module.unwrap_single();
		let shader_fmt = "SPV";
		
		println!("cargo::rustc-env=SHADER_PATH={}", path_to_shaders.display());
		println!("cargo::rustc-env=SHADER_FMT={}", shader_fmt);
	}
	
	Ok(())
}