Test if validation offsets times in the future

Use some mock gossiped peers that all have `last_seen` times in the
future and check that they all have a specific offset applied to them.

zebra-network/src/peer_set/candidate_set.rs

@@ -8,6 +8,9 @@ use zebra_chain::serialization::DateTime32;
 
 use crate::{constants, types::MetaAddr, AddressBook, BoxError, Request, Response};
 
+#[cfg(test)]
+mod tests;
+
 /// The `CandidateSet` manages the `PeerSet`'s peer reconnection attempts.
 ///
 /// It divides the set of all possible candidate peers into disjoint subsets,

zebra-network/src/peer_set/candidate_set/tests.rs

@@ -0,0 +1,3 @@
+//! [`CandidateSet`] tests.
+
+mod vectors;

zebra-network/src/peer_set/candidate_set/tests/vectors.rs

@@ -0,0 +1,56 @@
+use std::{
+    convert::TryInto,
+    net::{IpAddr, SocketAddr},
+};
+
+use chrono::{DateTime, Duration, Utc};
+
+use zebra_chain::serialization::DateTime32;
+
+use super::super::validate_addrs;
+use crate::types::{MetaAddr, PeerServices};
+
+/// Test that offset is applied when all addresses have `last_seen` times in the future.
+#[test]
+fn offsets_last_seen_times_in_the_future() {
+    let last_seen_limit = DateTime32::now();
+    let last_seen_limit_chrono = last_seen_limit.to_chrono();
+
+    let input_peers = mock_gossiped_peers(vec![
+        last_seen_limit_chrono + Duration::minutes(30),
+        last_seen_limit_chrono + Duration::minutes(15),
+        last_seen_limit_chrono + Duration::minutes(45),
+    ]);
+
+    let validated_peers: Vec<_> = validate_addrs(input_peers, last_seen_limit).collect();
+
+    let expected_offset = Duration::minutes(45);
+    let expected_peers = mock_gossiped_peers(vec![
+        last_seen_limit_chrono + Duration::minutes(30) - expected_offset,
+        last_seen_limit_chrono + Duration::minutes(15) - expected_offset,
+        last_seen_limit_chrono + Duration::minutes(45) - expected_offset,
+    ]);
+
+    assert_eq!(validated_peers, expected_peers);
+}
+
+/// Create a mock list of gossiped [`MetaAddr`]s with the specified `last_seen_times`.
+///
+/// The IP address and port of the generated ports should not matter for the test.
+fn mock_gossiped_peers(last_seen_times: impl IntoIterator<Item = DateTime<Utc>>) -> Vec<MetaAddr> {
+    last_seen_times
+        .into_iter()
+        .enumerate()
+        .map(|(index, last_seen_chrono)| {
+            let last_seen = last_seen_chrono
+                .try_into()
+                .expect("`last_seen` time doesn't fit in a `DateTime32`");
+
+            MetaAddr::new_gossiped_meta_addr(
+                SocketAddr::new(IpAddr::from([192, 168, 1, index as u8]), 20_000),
+                PeerServices::NODE_NETWORK,
+                last_seen,
+            )
+        })
+        .collect()
+}