0.3.5-alpha.8

crates/apps/game-realtime-transport-fallback-smoke/unit_tests/fallback.rs

@@ -0,0 +1,66 @@
+// file: crates/apps/game-realtime-transport-fallback-smoke/unit_tests/fallback.rs
+// version: 1
+
+#[test]
+fn fallback_policy_is_narrow_and_excludes_ambiguous_connect_failures() {
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::InvalidConfiguration));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Connect));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Bind));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Accept));
+    assert!(super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Timeout));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::MessageTooLarge));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Backpressure));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Closed));
+    assert!(super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Io));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Protocol));
+    assert!(!super::is_fallback_eligible(game_realtime_transport_lib::TransportErrorKind::Aborted));
+}
+
+#[tokio::test(flavor = "current_thread")]
+async fn selector_prefers_webtransport_and_falls_back_only_for_classified_errors() {
+    let preferred = super::select_preferred_transport(
+        || async {
+            return std::result::Result::<u8, game_realtime_transport_lib::TransportError>::Ok(7);
+        },
+        || async {
+            return std::result::Result::<u8, game_realtime_transport_lib::TransportError>::Err(test_error("fallback must not run"));
+        },
+    )
+    .await;
+    assert!(matches!(preferred, std::result::Result::Ok(super::SelectedConnection::WebTransport(7))), "WebTransport success must remain preferred");
+    let fallback = super::select_preferred_transport(
+        || async {
+            return std::result::Result::<u8, game_realtime_transport_lib::TransportError>::Err(game_realtime_transport_lib::TransportError::new(
+                game_realtime_transport_lib::TransportErrorKind::Timeout,
+                "forced timeout",
+            ));
+        },
+        || async {
+            return std::result::Result::<u8, game_realtime_transport_lib::TransportError>::Ok(9);
+        },
+    )
+    .await;
+    assert!(matches!(fallback, std::result::Result::Ok(super::SelectedConnection::WebSocket(9))), "classified timeout must select WebSocket fallback");
+    let non_fallback = super::select_preferred_transport(
+        || async {
+            return std::result::Result::<u8, game_realtime_transport_lib::TransportError>::Err(test_error("visible primary error"));
+        },
+        || async {
+            return std::result::Result::<u8, game_realtime_transport_lib::TransportError>::Ok(11);
+        },
+    )
+    .await;
+    assert!(
+        matches!(
+            &non_fallback,
+            std::result::Result::Err(error)
+                if error.kind() == game_realtime_transport_lib::TransportErrorKind::InvalidConfiguration
+                    && error.detail() == "visible primary error"
+        ),
+        "non-fallback errors must remain visible"
+    );
+}
+
+fn test_error(detail: &str) -> game_realtime_transport_lib::TransportError {
+    return game_realtime_transport_lib::TransportError::new(game_realtime_transport_lib::TransportErrorKind::InvalidConfiguration, detail);
+}