Merge pull request #1701 from TheBlueMatt/2022-09-feature-or

[rust-lightning] / lightning / src / ln / features.rs

diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs
index c978c61a3a563428e38f3368e557e544a6c623b9..91922f1a45f26748f9fdaf8c7ba009a068f6d6b9 100644 (file)
--- a/lightning/src/ln/features.rs
+++ b/lightning/src/ln/features.rs
@@ -163,6 +163,8 @@ mod sealed {
                        ,
                ],
                optional_features: [
+                       // Note that if new "non-channel-related" flags are added here they should be
+                       // explicitly cleared in InitFeatures::known_channel_features.
                        // Byte 0
                        DataLossProtect | InitialRoutingSync | UpfrontShutdownScript | GossipQueries,
                        // Byte 1
@@ -545,6 +547,14 @@ impl InitFeatures {
        pub(crate) fn to_context<C: sealed::Context>(&self) -> Features<C> {
                self.to_context_internal()
        }
+
+       /// Returns the set of known init features that are related to channels. At least some of
+       /// these features are likely required for peers to talk to us.
+       pub fn known_channel_features() -> InitFeatures {
+               Self::known()
+                       .clear_initial_routing_sync()
+                       .clear_gossip_queries()
+       }
 }
 
 impl InvoiceFeatures {
@@ -763,7 +773,6 @@ impl<T: sealed::UpfrontShutdownScript> Features<T> {
 
 
 impl<T: sealed::GossipQueries> Features<T> {
-       #[cfg(test)]
        pub(crate) fn clear_gossip_queries(mut self) -> Self {
                <T as sealed::GossipQueries>::clear_bits(&mut self.flags);
                self
@@ -771,12 +780,10 @@ impl<T: sealed::GossipQueries> Features<T> {
 }
 
 impl<T: sealed::InitialRoutingSync> Features<T> {
-       // We are no longer setting initial_routing_sync now that gossip_queries
-       // is enabled. This feature is ignored by a peer when gossip_queries has
-       // been negotiated.
-       #[cfg(test)]
-       pub(crate) fn clear_initial_routing_sync(&mut self) {
-               <T as sealed::InitialRoutingSync>::clear_bits(&mut self.flags)
+       // Note that initial_routing_sync is ignored if gossip_queries is set.
+       pub(crate) fn clear_initial_routing_sync(mut self) -> Self {
+               <T as sealed::InitialRoutingSync>::clear_bits(&mut self.flags);
+               self
        }
 }
 
@@ -915,7 +922,7 @@ mod tests {
 
                let mut init_features = InitFeatures::known();
                assert!(init_features.initial_routing_sync());
-               init_features.clear_initial_routing_sync();
+               init_features = init_features.clear_initial_routing_sync();
                assert!(!init_features.initial_routing_sync());
        }