Ensure htlc_maximum_msat is at least htlc_minimum_msat (#3117)

We previously checked only that it was greater or equal to the remote `htlc_minimum_msat` but not our local `htlc_minimum_msat`.

Author: thomash-acinq

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

@@ -356,7 +356,7 @@ object Helpers {
     }
     for (balanceThreshold <- nodeParams.channelConf.balanceThresholds) {
       if (commitments.availableBalanceForSend <= balanceThreshold.available) {
-        return balanceThreshold.maxHtlcAmount.toMilliSatoshi.max(commitments.params.remoteParams.htlcMinimum).min(commitments.params.maxHtlcAmount)
+        return balanceThreshold.maxHtlcAmount.toMilliSatoshi.max(commitments.params.remoteParams.htlcMinimum.max(commitments.params.localParams.htlcMinimum)).min(commitments.params.maxHtlcAmount)
       }
     }
     commitments.params.maxHtlcAmount

eclair-core/src/test/scala/fr/acinq/eclair/channel/states/e/NormalStateSpec.scala

@@ -937,7 +937,9 @@ class NormalStateSpec extends TestKitBaseClass with FixtureAnyFunSuiteLike with
     }
     assert(alice.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.channelFlags.isEnabled)
     inside(bobListener.expectMsgType[LocalChannelUpdate]) { lcu =>
-      assert(lcu.channelUpdate.htlcMaximumMsat == 0.msat)
+      assert(lcu.commitments.params.localParams.htlcMinimum == 1000.msat)
+      assert(lcu.commitments.params.remoteParams.htlcMinimum == 0.msat)
+      assert(lcu.channelUpdate.htlcMaximumMsat == 1000.msat)
       assert(lcu.channelUpdate.shortChannelId.isInstanceOf[RealShortChannelId])
       assert(lcu.channelUpdate.channelFlags.isEnabled)
     }
@@ -960,7 +962,7 @@ class NormalStateSpec extends TestKitBaseClass with FixtureAnyFunSuiteLike with
     aliceListener.expectNoMessage(100 millis)
     bobListener.expectNoMessage(100 millis)
     assert(alice.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.htlcMaximumMsat == 500_000_000.msat)
-    assert(bob.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.htlcMaximumMsat == 0.msat)
+    assert(bob.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.htlcMaximumMsat == 1000.msat)
 
     // Alice sends more funds, reaching Bob's third balance bucket and causing him to update his htlc_maximum_msat.
     val (p2, htlc2) = addHtlc(2_000_000 msat, alice, bob, alice2bob, bob2alice)
@@ -981,8 +983,8 @@ class NormalStateSpec extends TestKitBaseClass with FixtureAnyFunSuiteLike with
     crossSign(alice, bob, alice2bob, bob2alice)
     assert(alice.stateData.asInstanceOf[DATA_NORMAL].commitments.latest.localCommit.spec.toLocal == 989_500_000.msat)
     assert(bob.stateData.asInstanceOf[DATA_NORMAL].commitments.latest.localCommit.spec.toLocal == 10_500_000.msat)
-    assert(bobListener.expectMsgType[LocalChannelUpdate].channelUpdate.htlcMaximumMsat == 0.msat)
-    awaitCond(bob.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.htlcMaximumMsat == 0.msat)
+    assert(bobListener.expectMsgType[LocalChannelUpdate].channelUpdate.htlcMaximumMsat == 1000.msat)
+    awaitCond(bob.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.htlcMaximumMsat == 1000.msat)
     aliceListener.expectNoMessage(100 millis)
     assert(alice.stateData.asInstanceOf[DATA_NORMAL].channelUpdate.htlcMaximumMsat == 500_000_000.msat)