{"ast_node_type":"variable","tokens":[{"end":67,"kind":"keyword","start":0,"text":"let"}]}
    let mut args: Vec<&dyn AsRef<OsStr>> = vec![&"cargo", &"test"];
    // Pass all the default args + the user-specified ones.
    args.extend(test_args.test_args.iter().map(|s| s as &dyn AsRef<OsStr>));