test: fix advance time to account for ticks

src/ic-websocket-cdk/src/tests/integration_tests/g_messages_acknowledgement.rs

@@ -228,10 +228,9 @@ mod helpers {
             websocket_message.sequence_num,
             expected_websocket_message_sequence_number
         );
-        assert_eq!(
-            websocket_message.timestamp,
-            get_test_env().get_canister_time()
-        );
+        // testing the timestamp is difficult, since pocketic advances the time
+        // at every round (at every update call)
+        assert!(websocket_message.timestamp <= get_test_env().get_canister_time());
         assert_eq!(
             decode_websocket_service_message_content(&websocket_message.content),
             WebsocketServiceMessageContent::AckMessage(CanisterAckMessageContent {

src/ic-websocket-cdk/src/tests/integration_tests/utils/test_env.rs

@@ -101,10 +101,21 @@ impl TestEnv {
         self.advance_canister_time_ns(ms * NS_IN_MS);
     }
 
+    /// # Panics
+    /// If time is advanced for less than 100ns, due to an internal logic
+    /// that accounts for the time advanced in `tick`s.
     pub fn advance_canister_time_ns(&self, ns: u64) {
-        self.pic.advance_time(Duration::from_nanos(ns));
+        // when calling `tick`, the time on pic advances by 1ns,
+        // so we have to account for that difference here
+        let ticks = 0..100;
+        let advance_diff = ticks.len() as u64;
+        assert!(ns > advance_diff, "Cannot advance for less than 99ns");
+        self.pic
+            .advance_time(Duration::from_nanos(ns - advance_diff));
         // produce and advance by some blocks to fire eventual timers
         // see https://forum.dfinity.org/t/pocketic-multi-subnet-canister-testing/24901/4
-        self.pic.tick();
+        for _ in ticks {
+            self.pic.tick();
+        }
     }
 }