consensus: add consensus property tests

Author: fed-franz

consensus/tests/consensus_property.rs

@@ -0,0 +1,32 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+// Copyright (c) DUSK NETWORK. All rights reserved.
+
+use std::io::Cursor;
+
+use node_data::Serializable;
+use node_data::message::Message;
+use rand::rngs::StdRng;
+use rand::{Rng, SeedableRng};
+
+#[test]
+#[ignore = "fuzz-like deserialization; run manually"]
+// Randomized deserialization should never panic, even on malformed input.
+fn fuzz_message_deserialization_does_not_panic() {
+    let mut rng = StdRng::seed_from_u64(4242);
+
+    for _ in 0..1000 {
+        let len = rng.gen_range(0..512);
+        let mut bytes = vec![0u8; len];
+        rng.fill(&mut bytes[..]);
+
+        let result = std::panic::catch_unwind(|| {
+            let mut cursor = Cursor::new(bytes);
+            let _ = Message::read(&mut cursor);
+        });
+
+        assert!(result.is_ok(), "deserialization panicked");
+    }
+}