refactor(test): DRY up interop tests and un-ignore CLN tests

- Move test_receive_keysend into interop_tests! macro, removing
  per-file duplicates across CLN, LND, and Eclair
- Un-ignore test_cln_splice_in (will fail until rust-lightning
  bump past #4472, tracked in lightningdevkit#857)
- Remove unused supports_splice() from ExternalNode trait

Author: febyeji

tests/common/cln.rs

@@ -270,16 +270,6 @@ impl ExternalNode for TestClnNode {
 		Ok(channels)
 	}
 
-	// CLN v25 with --experimental-splicing advertises BOLT-spec bit 62
-	// (OPT_SPLICE), so feature negotiation with LDK succeeds. However,
-	// rust-lightning panics during tx_signatures exchange due to a
-	// debug_assert (fixed in rust-lightning#4472, not yet in pinned rev).
-	// Flip to true after ldk-node bumps rust-lightning past that fix.
-	// Tracking: ldk-node#857
-	fn supports_splice(&self) -> bool {
-		false
-	}
-
 	async fn splice_in(&self, channel_id: &str, amount_sat: u64) -> Result<(), TestFailure> {
 		// Step 1: splice_init with positive relative_amount
 		let ch_id = channel_id.to_string();

tests/common/eclair.rs

@@ -280,14 +280,6 @@ impl ExternalNode for TestEclairNode {
 		Ok(channels)
 	}
 
-	// Eclair uses custom prototype feature bit 154 for splice, not the
-	// BOLT-specified bit 62/63 that LDK uses. Splice interop is not possible
-	// until Eclair migrates to the standard feature bits.
-	// Ref: https://github.com/ACINQ/eclair/blob/master/eclair-core/src/main/scala/fr/acinq/eclair/Features.scala
-	fn supports_splice(&self) -> bool {
-		false
-	}
-
 	async fn splice_in(&self, channel_id: &str, amount_sat: u64) -> Result<(), TestFailure> {
 		let amount_str = amount_sat.to_string();
 		self.post("/splicein", &[("channelId", channel_id), ("amountIn", &amount_str)]).await?;

tests/common/external_node.rs

@@ -145,18 +145,6 @@ pub(crate) trait ExternalNode: Send + Sync {
 		Err(self.make_error(format!("did not reach height {} after 60s", min_height)))
 	}
 
-	/// Whether this implementation supports channel splicing with LDK.
-	///
-	/// Feature bit status:
-	/// - LDK uses BOLT-finalized bit 62/63 ([BOLT 9](https://github.com/lightning/bolts/blob/master/09-features.md))
-	/// - CLN v25 `--experimental-splicing` advertises both standard bit 62 and
-	///   experimental bit 162 ([features.h](https://github.com/ElementsProject/lightning/blob/v25.12/common/features.h)) -- interop works
-	/// - Eclair v0.14 uses custom prototype bit 154 ([Features.scala](https://github.com/ACINQ/eclair/blob/master/eclair-core/src/main/scala/fr/acinq/eclair/Features.scala)) -- not compatible
-	/// - LND does not implement splice
-	fn supports_splice(&self) -> bool {
-		false
-	}
-
 	/// Splice additional funds into an existing channel.
 	///
 	/// Not all implementations support splicing. The default returns `NotSupported`.

tests/common/scenarios/mod.rs

@@ -179,6 +179,28 @@ macro_rules! interop_tests {
 			.await;
 			node.stop().unwrap();
 		}
+
+		#[tokio::test(flavor = "multi_thread", worker_threads = 1)]
+		async fn test_receive_keysend() {
+			let (bitcoind, electrs, ext) = $setup_clients().await;
+			let node = setup_ldk_node();
+			common::scenarios::setup_interop_test(&node, &ext, &bitcoind, &electrs).await;
+			let (user_ch, _ext_ch) = common::scenarios::channel::open_channel_to_external(
+				&node,
+				&ext,
+				&bitcoind,
+				&electrs,
+				1_000_000,
+				Some(500_000_000),
+			)
+			.await;
+			common::scenarios::payment::receive_keysend_payment(&node, &ext, 5_000_000).await;
+			common::scenarios::channel::cooperative_close_by_ldk(
+				&node, &ext, &bitcoind, &electrs, &user_ch,
+			)
+			.await;
+			node.stop().unwrap();
+		}
 	};
 }
 

tests/integration_tests_cln.rs

@@ -15,7 +15,6 @@ use common::cln::TestClnNode;
 use common::external_node::ExternalNode;
 use common::scenarios::channel::{cooperative_close_by_ldk, open_channel_to_external};
 use common::scenarios::interop_tests;
-use common::scenarios::payment::receive_keysend_payment;
 use common::scenarios::setup_interop_test;
 use electrsd::corepc_client::client_sync::Auth;
 use electrsd::corepc_node::Client as BitcoindClient;
@@ -37,8 +36,12 @@ interop_tests!(setup_clients);
 
 /// Test splice-in: LDK adds funds to an existing LDK↔CLN channel.
 /// Requires CLN --experimental-splicing (advertises OPT_SPLICE bit 62).
+///
+/// Known issue: rust-lightning panics during tx_signatures exchange
+/// (channel.rs debug_assert). Fix merged in rust-lightning#4472 but not yet
+/// in the pinned rev. Will pass once ldk-node bumps rust-lightning.
+/// Tracking: ldk-node#857
 #[tokio::test(flavor = "multi_thread", worker_threads = 1)]
-#[ignore = "rust-lightning panics during tx_signatures exchange (channel.rs debug_assert), fix merged in rust-lightning#4472 but not yet in pinned rev, see ldk-node#857"]
 async fn test_cln_splice_in() {
 	let (bitcoind, electrs, cln) = setup_clients().await;
 	let node = setup_ldk_node();
@@ -66,20 +69,3 @@ async fn test_cln_splice_in() {
 	cooperative_close_by_ldk(&node, &cln, &bitcoind, &electrs, &user_ch).await;
 	node.stop().unwrap();
 }
-
-/// CLN keysend plugin sets min_final_cltv_expiry=22, but LDK requires at least
-/// 42 (HTLC_FAIL_BACK_BUFFER(39) + 3). CLN's keysend RPC has no parameter to
-/// override this value. See: plugins/keysend.c in CLN source.
-#[tokio::test(flavor = "multi_thread", worker_threads = 1)]
-#[ignore = "CLN keysend final_cltv=22 < LDK minimum 42 -- needs CLN upstream fix"]
-async fn test_cln_receive_keysend() {
-	let (bitcoind, electrs, cln) = setup_clients().await;
-	let node = setup_ldk_node();
-	setup_interop_test(&node, &cln, &bitcoind, &electrs).await;
-	let (user_ch, _ext_ch) =
-		open_channel_to_external(&node, &cln, &bitcoind, &electrs, 1_000_000, Some(500_000_000))
-			.await;
-	receive_keysend_payment(&node, &cln, 5_000_000).await;
-	cooperative_close_by_ldk(&node, &cln, &bitcoind, &electrs, &user_ch).await;
-	node.stop().unwrap();
-}

tests/integration_tests_eclair.rs

@@ -11,10 +11,7 @@ mod common;
 
 use base64::prelude::{Engine as _, BASE64_STANDARD};
 use common::eclair::TestEclairNode;
-use common::external_node::ExternalNode;
-use common::scenarios::channel::{cooperative_close_by_ldk, open_channel_to_external};
 use common::scenarios::interop_tests;
-use common::scenarios::payment::receive_keysend_payment;
 use common::scenarios::setup_interop_test;
 use electrsd::corepc_client::client_sync::Auth;
 use electrsd::corepc_node::Client as BitcoindClient;
@@ -50,16 +47,3 @@ async fn setup_clients() -> (BitcoindClient, ElectrumClient, TestEclairNode) {
 }
 
 interop_tests!(setup_clients);
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 1)]
-async fn test_eclair_receive_keysend() {
-	let (bitcoind, electrs, eclair) = setup_clients().await;
-	let node = setup_ldk_node();
-	setup_interop_test(&node, &eclair, &bitcoind, &electrs).await;
-	let (user_ch, _ext_ch) =
-		open_channel_to_external(&node, &eclair, &bitcoind, &electrs, 1_000_000, Some(500_000_000))
-			.await;
-	receive_keysend_payment(&node, &eclair, 5_000_000).await;
-	cooperative_close_by_ldk(&node, &eclair, &bitcoind, &electrs, &user_ch).await;
-	node.stop().unwrap();
-}

tests/integration_tests_lnd.rs

@@ -9,11 +9,8 @@
 
 mod common;
 
-use common::external_node::ExternalNode;
 use common::lnd::TestLndNode;
-use common::scenarios::channel::{cooperative_close_by_ldk, open_channel_to_external};
 use common::scenarios::interop_tests;
-use common::scenarios::payment::receive_keysend_payment;
 use common::scenarios::setup_interop_test;
 use electrsd::corepc_client::client_sync::Auth;
 use electrsd::corepc_node::Client as BitcoindClient;
@@ -32,16 +29,3 @@ async fn setup_clients() -> (BitcoindClient, ElectrumClient, TestLndNode) {
 }
 
 interop_tests!(setup_clients);
-
-#[tokio::test(flavor = "multi_thread", worker_threads = 1)]
-async fn test_lnd_receive_keysend() {
-	let (bitcoind, electrs, lnd) = setup_clients().await;
-	let node = setup_ldk_node();
-	setup_interop_test(&node, &lnd, &bitcoind, &electrs).await;
-	let (user_ch, _ext_ch) =
-		open_channel_to_external(&node, &lnd, &bitcoind, &electrs, 1_000_000, Some(500_000_000))
-			.await;
-	receive_keysend_payment(&node, &lnd, 5_000_000).await;
-	cooperative_close_by_ldk(&node, &lnd, &bitcoind, &electrs, &user_ch).await;
-	node.stop().unwrap();
-}