PVF: Add worker check during tests and benches (#1771)

polkadot/node/core/pvf/src/lib.rs

@@ -116,5 +116,18 @@ pub use polkadot_node_core_pvf_common::{
 	SecurityStatus,
 };
 
+use std::{path::Path, process::Command};
+
 /// The log target for this crate.
 pub const LOG_TARGET: &str = "parachain::pvf";
+
+/// Utility to get the version of a worker, used for version checks.
+///
+/// The worker's existence at the given path must be checked separately.
+pub fn get_worker_version(worker_path: &Path) -> std::io::Result<String> {
+	let worker_version = Command::new(worker_path).args(["--version"]).output()?.stdout;
+	Ok(std::str::from_utf8(&worker_version)
+		.expect("version is printed as a string; qed")
+		.trim()
+		.to_string())
+}