Various nits

eclair-core/src/main/scala/fr/acinq/eclair/channel/ChannelData.scala

@@ -429,10 +429,14 @@ final case class DATA_WAIT_FOR_FUNDING_CONFIRMED(commitments: Commitments,
 final case class DATA_WAIT_FOR_CHANNEL_READY(commitments: Commitments,
                                              shortIds: ShortIds,
                                              lastSent: ChannelReady) extends PersistentChannelData
+
 sealed trait RealScidStatus { def toOption: Option[RealShortChannelId] }
 object RealScidStatus {
+  /** The funding transaction has been confirmed but hasn't reached min_depth, we must be ready for a reorg. */
   case class Temporary(realScid: RealShortChannelId) extends RealScidStatus { override def toOption: Option[RealShortChannelId] = Some(realScid) }
+  /** The funding transaction has been deeply confirmed. */
   case class Final(realScid: RealShortChannelId) extends RealScidStatus { override def toOption: Option[RealShortChannelId] = Some(realScid) }
+  /** The funding transaction is not confirmed. */
   case object Unknown extends RealScidStatus { override def toOption: Option[RealShortChannelId] = None }
 }
 
@@ -441,7 +445,7 @@ object RealScidStatus {
  *
  * @param real            the real scid, it may change if a reorg happens before the channel reaches 6 conf
  * @param localAlias      we must remember the alias that we sent to our peer because we use it to:
- *                          - identify incoming [[ChannelUpdate]]
+ *                          - identify incoming [[ChannelUpdate]] at the connection level
  *                          - route outgoing payments to that channel
  * @param remoteAlias_opt we only remember the last alias received from our peer, we use this to generate
  *                        routing hints in [[fr.acinq.eclair.payment.Bolt11Invoice]]

eclair-core/src/main/scala/fr/acinq/eclair/channel/ChannelEvents.scala

@@ -19,10 +19,10 @@ package fr.acinq.eclair.channel
 import akka.actor.ActorRef
 import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
 import fr.acinq.bitcoin.scalacompat.{ByteVector32, Satoshi, Transaction}
-import fr.acinq.eclair.{BlockHeight, Features, Alias, RealShortChannelId, ShortChannelId}
 import fr.acinq.eclair.blockchain.fee.FeeratePerKw
 import fr.acinq.eclair.channel.Helpers.Closing.ClosingType
 import fr.acinq.eclair.wire.protocol.{ChannelAnnouncement, ChannelUpdate}
+import fr.acinq.eclair.{BlockHeight, Features, ShortChannelId}
 
 /**
  * Created by PM on 17/08/2016.
@@ -51,15 +51,18 @@ case class ShortChannelIdAssigned(channel: ActorRef, channelId: ByteVector32, sh
 
 case class LocalChannelUpdate(channel: ActorRef, channelId: ByteVector32, shortIds: ShortIds, remoteNodeId: PublicKey, channelAnnouncement_opt: Option[ChannelAnnouncement], channelUpdate: ChannelUpdate, commitments: AbstractCommitments) extends ChannelEvent {
   /**
-   * We always map the local alias because we must always be able to route based on it
-   * However we only map the real scid if option_scid_alias (TODO: rename to option_scid_privacy) is disabled
+   * We always include the local alias because we must always be able to route based on it.
+   * However we only include the real scid if option_scid_alias is disabled, because we otherwise want to hide it.
    */
   def scidsForRouting: Seq[ShortChannelId] = {
-    commitments match {
-      case c: Commitments =>
-        val realScid_opt = if (c.channelFeatures.hasFeature(Features.ScidAlias)) None else shortIds.real.toOption
-        realScid_opt.toSeq :+ shortIds.localAlias
-      case _ => Seq(shortIds.localAlias) // TODO: ugly
+    val canUseRealScid = commitments match {
+      case c: Commitments => !c.channelFeatures.hasFeature(Features.ScidAlias)
+      case _ => false
+    }
+    if (canUseRealScid) {
+      shortIds.real.toOption.toSeq :+ shortIds.localAlias
+    } else {
+      Seq(shortIds.localAlias)
     }
   }
 }

eclair-core/src/main/scala/fr/acinq/eclair/channel/ChannelFeatures.scala

@@ -115,7 +115,7 @@ object ChannelTypes {
     ).flatten
     override def paysDirectlyToWallet: Boolean = false
     override def commitmentFormat: CommitmentFormat = ZeroFeeHtlcTxAnchorOutputsCommitmentFormat
-    override def toString: String = s"anchor_outputs_zero_fee_htlc_tx${if (scidAlias) "+scid_alias" else ""}${if (zeroConf) "+zeroconf" else ""}"
+    override def toString: String = s"anchor_outputs_zero_fee_htlc_tx${if (scidAlias) "+scid_alias" else ""}${if (zeroConf) "+zero_conf" else ""}"
   }
   case class UnsupportedChannelType(featureBits: Features[InitFeature]) extends ChannelType {
     override def features: Set[InitFeature] = featureBits.activated.keySet

eclair-core/src/main/scala/fr/acinq/eclair/channel/Helpers.scala

@@ -21,6 +21,7 @@ import fr.acinq.bitcoin.ScriptFlags
 import fr.acinq.bitcoin.scalacompat.Crypto.{PrivateKey, PublicKey, sha256}
 import fr.acinq.bitcoin.scalacompat.Script._
 import fr.acinq.bitcoin.scalacompat._
+import fr.acinq.eclair._
 import fr.acinq.eclair.blockchain.OnChainAddressGenerator
 import fr.acinq.eclair.blockchain.fee.{FeeEstimator, FeeTargets, FeeratePerKw}
 import fr.acinq.eclair.channel.fsm.Channel
@@ -35,7 +36,6 @@ import fr.acinq.eclair.transactions.Scripts._
 import fr.acinq.eclair.transactions.Transactions._
 import fr.acinq.eclair.transactions._
 import fr.acinq.eclair.wire.protocol._
-import fr.acinq.eclair.{RealShortChannelId, _}
 import scodec.bits.ByteVector
 
 import scala.concurrent.duration._
@@ -196,17 +196,17 @@ object Helpers {
    *    - before channel announcement: use remote_alias
    *    - after channel announcement: use real scid
    *  - no remote_alias from peer
-   *    - min_depth > 0 : use real scid (may change if reorg between min_depth and 6 conf)
-   *    - min_depth = 0 (zero-conf) : unsupported
+   *    - min_depth > 0: use real scid (may change if reorg between min_depth and 6 conf)
+   *    - min_depth = 0 (zero-conf): spec violation, our peer MUST send an alias when using zero-conf
    */
-  def scidForChannelUpdate(channelAnnouncement_opt: Option[ChannelAnnouncement], shortIds: ShortIds)(implicit log: DiagnosticLoggingAdapter): ShortChannelId = {
+  def scidForChannelUpdate(channelAnnouncement_opt: Option[ChannelAnnouncement], shortIds: ShortIds): ShortChannelId = {
     channelAnnouncement_opt.map(_.shortChannelId) // we use the real "final" scid when it is publicly announced
       .orElse(shortIds.remoteAlias_opt) // otherwise the remote alias
       .orElse(shortIds.real.toOption) // if we don't have a remote alias, we use the real scid (which could change because the funding tx possibly has less than 6 confs here)
       .getOrElse(throw new RuntimeException("this is a zero-conf channel and no alias was provided in channel_ready")) // if we don't have a real scid, it means this is a zero-conf channel and our peer must have sent an alias
   }
 
-  def scidForChannelUpdate(d: DATA_NORMAL)(implicit log: DiagnosticLoggingAdapter): ShortChannelId = scidForChannelUpdate(d.channelAnnouncement, d.shortIds)
+  def scidForChannelUpdate(d: DATA_NORMAL): ShortChannelId = scidForChannelUpdate(d.channelAnnouncement, d.shortIds)
 
   /**
    * Compute the delay until we need to refresh the channel_update for our channel not to be considered stale by

eclair-core/src/main/scala/fr/acinq/eclair/channel/Register.scala

@@ -49,7 +49,7 @@ class Register extends Actor with ActorLogging {
 
     case scidAssigned: ShortChannelIdAssigned =>
       // We map all known scids (real or alias) to the channel_id. The relayer is in charge of deciding whether a real
-      // scid can be used or not for routing (see option_scid_privacy), but the register is neutral.
+      // scid can be used or not for routing (see option_scid_alias), but the register is neutral.
       val m = (scidAssigned.shortIds.real.toOption.toSeq :+ scidAssigned.shortIds.localAlias).map(_ -> scidAssigned.channelId).toMap
       context become main(channels, shortIds ++ m, channelsTo)
 

eclair-core/src/main/scala/fr/acinq/eclair/wire/internal/channel/version3/ChannelCodecs3.scala

@@ -410,7 +410,7 @@ private[channel] object ChannelCodecs3 {
 
   // Order matters!
   val channelDataCodec: Codec[PersistentChannelData] = discriminated[PersistentChannelData].by(uint16)
-    .typecase(0x10, Codecs.DATA_WAIT_FOR_CHANNEL_READY_Codec)
+    .typecase(0x0a, Codecs.DATA_WAIT_FOR_CHANNEL_READY_Codec)
     .typecase(0x09, Codecs.DATA_NORMAL_Codec)
     .typecase(0x08, Codecs.DATA_SHUTDOWN_Codec)
     .typecase(0x07, Codecs.DATA_NORMAL_COMPAT_07_Codec)

eclair-core/src/test/scala/fr/acinq/eclair/wire/internal/channel/version3/ChannelCodecs3Spec.scala

@@ -257,7 +257,7 @@ class ChannelCodecs3Spec extends AnyFunSuite {
       assert(data.shortIds.localAlias == ShortChannelId(123456789L))
       assert(data.shortIds.real == RealScidStatus.Temporary(RealShortChannelId(123456789L)))
       val binMigrated = channelDataCodec.encode(data).require.toHex
-      assert(binMigrated.startsWith("0010")) // NB: 01 -> 10
+      assert(binMigrated.startsWith("000a")) // NB: 01 -> 0a
     }
 
     {