Function install_environment

pre_commit/languages/rust.py:113–160

(
        prefix: Prefix,
        version: str,
        additional_dependencies: Sequence[str],
)

def install_environment(
        prefix: Prefix,
        version: str,
        additional_dependencies: Sequence[str],
) -> None:
    envdir = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)

    # There are two cases where we might want to specify more dependencies:
    # as dependencies for the library being built, and as binary packages
    # to be `cargo install`'d.
    #
    # Unlike e.g. Python, if we just `cargo install` a library, it won't be
    # used for compilation. And if we add a crate providing a binary to the
    # `Cargo.toml`, the binary won't be built.
    #
    # Because of this, we allow specifying "cli" dependencies by prefixing
    # with 'cli:'.
    cli_deps = {
        dep for dep in additional_dependencies if dep.startswith('cli:')
    }
    lib_deps = set(additional_dependencies) - cli_deps

    packages_to_install: set[tuple[str, ...]] = {('--path', '.')}
    for cli_dep in cli_deps:
        cli_dep = cli_dep.removeprefix('cli:')
        package, _, crate_version = cli_dep.partition(':')
        if crate_version != '':
            packages_to_install.add((package, '--version', crate_version))
        else:
            packages_to_install.add((package,))

    with contextlib.ExitStack() as ctx:
        ctx.enter_context(in_env(prefix, version))

        if version != 'system':
            install_rust_with_toolchain(_rust_toolchain(version), envdir)

            tmpdir = ctx.enter_context(tempfile.TemporaryDirectory())
            ctx.enter_context(envcontext((('RUSTUP_HOME', tmpdir),)))

        if len(lib_deps) > 0:
            _add_dependencies(prefix, lib_deps)

        for args in packages_to_install:
            cmd_output_b(
                'cargo', 'install', '--bins', '--root', envdir, *args,
                cwd=prefix.prefix_dir,
            )