Fix TLV tag for splice liquidity ads

And add codec unit tests for splice messages matching the tests from
`lightning-kmp`.

Author: t-bast

eclair-core/src/main/scala/fr/acinq/eclair/wire/protocol/ChannelTlv.scala

@@ -156,7 +156,7 @@ object SpliceInitTlv {
   val spliceInitTlvCodec: Codec[TlvStream[SpliceInitTlv]] = tlvStream(discriminated[SpliceInitTlv].by(varint)
     .typecase(UInt64(2), requireConfirmedInputsCodec)
     // We use a temporary TLV while the spec is being reviewed.
-    .typecase(UInt64(1399), requestFundingCodec)
+    .typecase(UInt64(1339), requestFundingCodec)
     .typecase(UInt64(0x47000007), tlvField(tmillisatoshi.as[PushAmountTlv]))
   )
 }

eclair-core/src/main/scala/fr/acinq/eclair/wire/protocol/LightningMessageTypes.scala

@@ -311,7 +311,7 @@ case class SpliceInit(channelId: ByteVector32,
 object SpliceInit {
   def apply(channelId: ByteVector32, fundingContribution: Satoshi, lockTime: Long, feerate: FeeratePerKw, fundingPubKey: PublicKey, pushAmount: MilliSatoshi, requireConfirmedInputs: Boolean, requestFunding_opt: Option[LiquidityAds.RequestFunding]): SpliceInit = {
     val tlvs: Set[SpliceInitTlv] = Set(
-      Some(ChannelTlv.PushAmountTlv(pushAmount)),
+      if (pushAmount > 0.msat) Some(ChannelTlv.PushAmountTlv(pushAmount)) else None,
       if (requireConfirmedInputs) Some(ChannelTlv.RequireConfirmedInputsTlv()) else None,
       requestFunding_opt.map(ChannelTlv.RequestFundingTlv)
     ).flatten
@@ -331,7 +331,7 @@ case class SpliceAck(channelId: ByteVector32,
 object SpliceAck {
   def apply(channelId: ByteVector32, fundingContribution: Satoshi, fundingPubKey: PublicKey, pushAmount: MilliSatoshi, requireConfirmedInputs: Boolean, willFund_opt: Option[LiquidityAds.WillFund]): SpliceAck = {
     val tlvs: Set[SpliceAckTlv] = Set(
-      Some(ChannelTlv.PushAmountTlv(pushAmount)),
+      if (pushAmount > 0.msat) Some(ChannelTlv.PushAmountTlv(pushAmount)) else None,
       if (requireConfirmedInputs) Some(ChannelTlv.RequireConfirmedInputsTlv()) else None,
       willFund_opt.map(ChannelTlv.ProvideFundingTlv)
     ).flatten

eclair-core/src/test/scala/fr/acinq/eclair/wire/protocol/LightningMessageCodecsSpec.scala

@@ -18,7 +18,7 @@ package fr.acinq.eclair.wire.protocol
 
 import com.google.common.base.Charsets
 import fr.acinq.bitcoin.scalacompat.Crypto.{PrivateKey, PublicKey}
-import fr.acinq.bitcoin.scalacompat.{Block, BlockHash, ByteVector32, ByteVector64, OutPoint, SatoshiLong, Script, ScriptWitness, Transaction, TxId}
+import fr.acinq.bitcoin.scalacompat.{Block, BlockHash, ByteVector32, ByteVector64, OutPoint, SatoshiLong, Script, ScriptWitness, Transaction, TxHash, TxId}
 import fr.acinq.eclair.FeatureSupport.Optional
 import fr.acinq.eclair.Features.DataLossProtect
 import fr.acinq.eclair.TestUtils.randomTxId
@@ -366,6 +366,34 @@ class LightningMessageCodecsSpec extends AnyFunSuite {
     }
   }
 
+  test("encode/decode splice messages") {
+    val channelId = ByteVector32(hex"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")
+    val fundingTxId = TxId(TxHash(ByteVector32(hex"24e1b2c94c4e734dd5b9c5f3c910fbb6b3b436ced6382c7186056a5a23f14566")))
+    val fundingPubkey = PublicKey(hex"0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798")
+    val fundingRate = LiquidityAds.FundingRate(100_000.sat, 100_000.sat, 400, 150, 0.sat, 0.sat)
+    val testCases = Seq(
+      // @formatter:off
+      SpliceInit(channelId, 100_000 sat, FeeratePerKw(2500 sat), 100, fundingPubkey) -> hex"9088 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 00000000000186a0 000009c4 00000064 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+      SpliceInit(channelId, 150_000 sat, 100, FeeratePerKw(2500 sat), fundingPubkey, 25_000_000 msat, requireConfirmedInputs = false, None) -> hex"9088 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 00000000000249f0 000009c4 00000064 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798 fe4700000704017d7840",
+      SpliceInit(channelId, 0 sat, FeeratePerKw(500 sat), 0, fundingPubkey) -> hex"9088 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 0000000000000000 000001f4 00000000 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+      SpliceInit(channelId, (-50_000).sat, FeeratePerKw(500 sat), 0, fundingPubkey) -> hex"9088 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa ffffffffffff3cb0 000001f4 00000000 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+      SpliceInit(channelId, 100_000 sat, 100, FeeratePerKw(2500 sat), fundingPubkey, 0 msat, requireConfirmedInputs = false, Some(LiquidityAds.RequestFunding(100_000 sat, fundingRate, LiquidityAds.PaymentDetails.FromChannelBalance))) -> hex"9088 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 00000000000186a0 000009c4 00000064 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798 fd053b1e00000000000186a0000186a0000186a00190009600000000000000000000",
+      SpliceAck(channelId, 25_000 sat, fundingPubkey) -> hex"908a aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 00000000000061a8 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+      SpliceAck(channelId, 40_000 sat, fundingPubkey, 10_000_000 msat, requireConfirmedInputs = false, None) -> hex"908a aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 0000000000009c40 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798 fe4700000703989680",
+      SpliceAck(channelId, 0 sat, fundingPubkey) -> hex"908a aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 0000000000000000 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+      SpliceAck(channelId, (-25_000).sat, fundingPubkey) -> hex"908a aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa ffffffffffff9e58 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
+      SpliceAck(channelId, 25_000 sat, fundingPubkey, 0 msat, requireConfirmedInputs = false, Some(LiquidityAds.WillFund(fundingRate, hex"deadbeef", ByteVector64.Zeroes))) -> hex"908a aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 00000000000061a8 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798 fd053b5a000186a0000186a00190009600000000000000000004deadbeef00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+      SpliceLocked(channelId, fundingTxId) -> hex"908c aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 24e1b2c94c4e734dd5b9c5f3c910fbb6b3b436ced6382c7186056a5a23f14566",
+      // @formatter:on
+    )
+    testCases.foreach { case (message, bin) =>
+      val decoded = lightningMessageCodec.decode(bin.bits).require.value
+      assert(decoded == message)
+      val encoded = lightningMessageCodec.encode(message).require.bytes
+      assert(encoded == bin)
+    }
+  }
+
   test("encode/decode closing_signed") {
     val defaultSig = ByteVector64(hex"01010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101")
     val testCases = Seq(