Remove dual_funding cfg-flags

Since we now have release branches, and dual-funded channels are expected
in v0.2.0, we can remove the cfg flags. This should also speed up CI a
bit as a bonus.

Author: dunxen

Cargo.toml

@@ -66,5 +66,4 @@ check-cfg = [
     "cfg(require_route_graph_test)",
     "cfg(splicing)",
     "cfg(async_payments)",
-    "cfg(dual_funding)",
 ]

lightning/src/ln/channel.rs

@@ -1147,7 +1147,6 @@ enum ChannelPhase<SP: Deref> where SP::Target: SignerProvider {
 	Undefined,
 	UnfundedOutboundV1(OutboundV1Channel<SP>),
 	UnfundedInboundV1(InboundV1Channel<SP>),
-	#[allow(dead_code)] // TODO(dual_funding): Remove once creating V2 channels is enabled.
 	UnfundedV2(PendingV2Channel<SP>),
 	Funded(FundedChannel<SP>),
 }
@@ -1333,7 +1332,6 @@ impl<SP: Deref> Channel<SP> where
 				debug_assert!(false);
 				ReconnectionMsg::None
 			},
-			#[cfg(dual_funding)]
 			ChannelPhase::UnfundedV2(chan) => {
 				if chan.context.is_outbound() {
 					ReconnectionMsg::Open(OpenChannelMessage::V2(
@@ -1347,8 +1345,6 @@ impl<SP: Deref> Channel<SP> where
 					ReconnectionMsg::None
 				}
 			},
-			#[cfg(not(dual_funding))]
-			ChannelPhase::UnfundedV2(_) => ReconnectionMsg::None,
 		}
 	}
 
@@ -1368,7 +1364,6 @@ impl<SP: Deref> Channel<SP> where
 					.map(|msg| Some(OpenChannelMessage::V1(msg)))
 			},
 			ChannelPhase::UnfundedInboundV1(_) => Ok(None),
-			#[cfg(dual_funding)]
 			ChannelPhase::UnfundedV2(chan) => {
 				if chan.context.is_outbound() {
 					chan.maybe_handle_error_without_close(chain_hash, fee_estimator)
@@ -1377,11 +1372,6 @@ impl<SP: Deref> Channel<SP> where
 					Ok(None)
 				}
 			},
-			#[cfg(not(dual_funding))]
-			ChannelPhase::UnfundedV2(_) => {
-				debug_assert!(false);
-				Ok(None)
-			},
 		}
 	}
 
@@ -4386,7 +4376,7 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider {
 		})
 	}
 
-	#[cfg(all(test, dual_funding))]
+	#[cfg(all(test))]
 	pub fn get_initial_counterparty_commitment_signature_for_test<L: Deref>(
 		&mut self, logger: &L, channel_transaction_parameters: ChannelTransactionParameters,
 		counterparty_cur_commitment_point_override: PublicKey,
@@ -9154,7 +9144,6 @@ impl<SP: Deref> PendingV2Channel<SP> where SP::Target: SignerProvider {
 	/// If we receive an error message, it may only be a rejection of the channel type we tried,
 	/// not of our ability to open any channel at all. Thus, on error, we should first call this
 	/// and see if we get a new `OpenChannelV2` message, otherwise the channel is failed.
-	#[cfg(dual_funding)]
 	pub(crate) fn maybe_handle_error_without_close<F: Deref>(
 		&mut self, chain_hash: ChainHash, fee_estimator: &LowerBoundedFeeEstimator<F>
 	) -> Result<msgs::OpenChannelV2, ()>
@@ -9165,7 +9154,6 @@ impl<SP: Deref> PendingV2Channel<SP> where SP::Target: SignerProvider {
 		Ok(self.get_open_channel_v2(chain_hash))
 	}
 
-	#[cfg(dual_funding)]
 	pub fn get_open_channel_v2(&self, chain_hash: ChainHash) -> msgs::OpenChannelV2 {
 		if !self.context.is_outbound() {
 			debug_assert!(false, "Tried to send open_channel2 for an inbound channel?");

lightning/src/ln/channelmanager.rs

@@ -49,7 +49,6 @@ use crate::ln::inbound_payment;
 use crate::ln::types::ChannelId;
 use crate::types::payment::{PaymentHash, PaymentPreimage, PaymentSecret};
 use crate::ln::channel::{self, Channel, ChannelError, ChannelUpdateStatus, FundedChannel, ShutdownResult, UpdateFulfillCommitFetch, OutboundV1Channel, ReconnectionMsg, InboundV1Channel, WithChannelContext};
-#[cfg(any(dual_funding, splicing))]
 use crate::ln::channel::PendingV2Channel;
 use crate::ln::channel_state::ChannelDetails;
 use crate::types::features::{Bolt12InvoiceFeatures, ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
@@ -1441,13 +1440,11 @@ impl <SP: Deref> PeerState<SP> where SP::Target: SignerProvider {
 #[derive(Clone)]
 pub(super) enum OpenChannelMessage {
 	V1(msgs::OpenChannel),
-	#[cfg(dual_funding)]
 	V2(msgs::OpenChannelV2),
 }
 
 pub(super) enum OpenChannelMessageRef<'a> {
 	V1(&'a msgs::OpenChannel),
-	#[cfg(dual_funding)]
 	V2(&'a msgs::OpenChannelV2),
 }
 
@@ -7828,7 +7825,6 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 							(*temporary_channel_id, Channel::from(channel), message_send_event)
 						})
 					},
-					#[cfg(dual_funding)]
 					OpenChannelMessage::V2(open_channel_msg) => {
 						PendingV2Channel::new_inbound(
 							&self.fee_estimator, &self.entropy_source, &self.signer_provider,
@@ -7991,7 +7987,6 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 	fn internal_open_channel(&self, counterparty_node_id: &PublicKey, msg: OpenChannelMessageRef<'_>) -> Result<(), MsgHandleErrInternal> {
 		let common_fields = match msg {
 			OpenChannelMessageRef::V1(msg) => &msg.common_fields,
-			#[cfg(dual_funding)]
 			OpenChannelMessageRef::V2(msg) => &msg.common_fields,
 		};
 
@@ -8069,7 +8064,6 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 				funding_satoshis: common_fields.funding_satoshis,
 				channel_negotiation_type: match msg {
 					OpenChannelMessageRef::V1(msg) => InboundChannelFunds::PushMsat(msg.push_msat),
-					#[cfg(dual_funding)]
 					OpenChannelMessageRef::V2(_) => InboundChannelFunds::DualFunded,
 				},
 				channel_type,
@@ -8079,7 +8073,6 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 			peer_state.inbound_channel_request_by_id.insert(channel_id, InboundChannelRequest {
 				open_channel_msg: match msg {
 					OpenChannelMessageRef::V1(msg) => OpenChannelMessage::V1(msg.clone()),
-					#[cfg(dual_funding)]
 					OpenChannelMessageRef::V2(msg) => OpenChannelMessage::V2(msg.clone()),
 				},
 				ticks_remaining: UNACCEPTED_INBOUND_CHANNEL_AGE_LIMIT_TICKS,
@@ -8115,7 +8108,6 @@ This indicates a bug inside LDK. Please report this error at https://github.com/
 				});
 				(Channel::from(channel), message_send_event)
 			},
-			#[cfg(dual_funding)]
 			OpenChannelMessageRef::V2(msg) => {
 				let channel = PendingV2Channel::new_inbound(
 					&self.fee_estimator, &self.entropy_source, &self.signer_provider,
@@ -11475,7 +11467,6 @@ where
 		// Note that we never need to persist the updated ChannelManager for an inbound
 		// open_channel message - pre-funded channels are never written so there should be no
 		// change to the contents.
-		#[cfg(dual_funding)]
 		let _persistence_guard = PersistenceNotifierGuard::optionally_notify(self, || {
 			let res = self.internal_open_channel(&counterparty_node_id, OpenChannelMessageRef::V2(msg));
 			let persist = match &res {
@@ -11488,10 +11479,6 @@ where
 			let _ = handle_error!(self, res, counterparty_node_id);
 			persist
 		});
-		#[cfg(not(dual_funding))]
-		let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
-			"Dual-funded channels not supported".to_owned(),
-			msg.common_fields.temporary_channel_id.clone())), counterparty_node_id);
 	}
 
 	fn handle_accept_channel(&self, counterparty_node_id: PublicKey, msg: &msgs::AcceptChannel) {
@@ -11879,7 +11866,6 @@ where
 								node_id: chan.context().get_counterparty_node_id(),
 								msg,
 							}),
-						#[cfg(dual_funding)]
 						ReconnectionMsg::Open(OpenChannelMessage::V2(msg)) =>
 							pending_msg_events.push(events::MessageSendEvent::SendOpenChannelV2 {
 								node_id: chan.context().get_counterparty_node_id(),
@@ -11986,7 +11972,6 @@ where
 							});
 							return;
 						},
-						#[cfg(dual_funding)]
 						Ok(Some(OpenChannelMessage::V2(msg))) => {
 							peer_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannelV2 {
 								node_id: counterparty_node_id,
@@ -12556,7 +12541,6 @@ pub fn provided_init_features(config: &UserConfig) -> InitFeatures {
 	if config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx {
 		features.set_anchors_zero_fee_htlc_tx_optional();
 	}
-	#[cfg(dual_funding)]
 	features.set_dual_fund_optional();
 	features
 }

lightning/src/ln/dual_funding_tests.rs

@@ -9,7 +9,6 @@
 
 //! Tests that test the creation of dual-funded channels in ChannelManager.
 
-#[cfg(dual_funding)]
 use {
 	crate::chain::chaininterface::{ConfirmationTarget, LowerBoundedFeeEstimator},
 	crate::events::{Event, MessageSendEvent, MessageSendEventsProvider},
@@ -29,14 +28,12 @@ use {
 	crate::util::test_utils,
 };
 
-#[cfg(dual_funding)]
 // Dual-funding: V2 Channel Establishment Tests
 struct V2ChannelEstablishmentTestSession {
 	funding_input_sats: u64,
 	initiator_input_value_satoshis: u64,
 }
 
-#[cfg(dual_funding)]
 // TODO(dual_funding): Use real node and API for creating V2 channels as initiator when available,
 // instead of manually constructing messages.
 fn do_test_v2_channel_establishment(
@@ -247,7 +244,6 @@ fn do_test_v2_channel_establishment(
 }
 
 #[test]
-#[cfg(dual_funding)]
 fn test_v2_channel_establishment() {
 	// Only initiator contributes, no persist pending
 	do_test_v2_channel_establishment(

lightning/src/ln/peer_handler.rs

@@ -346,7 +346,6 @@ impl ChannelMessageHandler for ErroringMessageHandler {
 		features.set_basic_mpp_optional();
 		features.set_wumbo_optional();
 		features.set_shutdown_any_segwit_optional();
-		#[cfg(dual_funding)]
 		features.set_dual_fund_optional();
 		features.set_channel_type_optional();
 		features.set_scid_privacy_optional();