pub fn platform_features(&self, build_platform: BuildPlatform) -> &FeatureSet<'g> {
        match build_platform {
            BuildPlatform::Target => self.target_features(),
            BuildPlatform::Host => self.host_features(),
        }
    }
Returns the feature set enabled on the specified build platform.
guppy/src/graph/cargo/cargo_api.rs