itest: extend testSupplyCommitIgnoreAsset to check peer commit retrieval

Extend the testSupplyCommitIgnoreAsset integration test to verify that
the verifying peer node correctly processes the supply commitment and
that the commitment can be retrieved from this peer.

Author: ffranr

itest/supply_commit_test.go

@@ -3,6 +3,7 @@ package itest
 import (
 	"bytes"
 	"context"
+	"strings"
 	"time"
 
 	"github.com/btcsuite/btcd/btcec/v2"
@@ -586,6 +587,60 @@ func testSupplyCommitIgnoreAsset(t *harnessTest) {
 		t.t, rpcAsset.Amount,
 		uniFetchResp.IgnoreSubtreeRoot.RootNode.RootSum,
 	)
+
+	t.Log("Attempting to fetch supply commit from secondary node")
+
+	var peerFetchResp *unirpc.FetchSupplyCommitResponse
+	require.Eventually(t.t, func() bool {
+		// nolint: lll
+		peerFetchResp, err = secondTapd.FetchSupplyCommit(
+			ctxb, &unirpc.FetchSupplyCommitRequest{
+				GroupKey: &unirpc.FetchSupplyCommitRequest_GroupKeyBytes{
+					GroupKeyBytes: groupKeyBytes,
+				},
+				Locator: &unirpc.FetchSupplyCommitRequest_VeryFirst{
+					VeryFirst: true,
+				},
+			},
+		)
+		if err != nil &&
+			strings.Contains(err.Error(), "commitment not found") {
+
+			return false
+		}
+		require.NoError(t.t, err)
+
+		// If the fetch response has no block height or hash,
+		// it means that the supply commitment transaction has not
+		// been mined yet, so we should retry.
+		if peerFetchResp.ChainData.BlockHeight == 0 ||
+			len(peerFetchResp.ChainData.BlockHash) == 0 {
+
+			return false
+		}
+
+		// Once the ignore tree includes the ignored asset outpoint, we
+		// know that the supply commitment has been updated.
+		if peerFetchResp.IgnoreSubtreeRoot == nil {
+			return false
+		}
+
+		return true
+	}, defaultWaitTimeout, time.Second)
+
+	require.NotNil(t.t, peerFetchResp)
+	require.Len(t.t, peerFetchResp.IssuanceLeaves, 1)
+	require.Len(t.t, peerFetchResp.BurnLeaves, 0)
+	require.Len(t.t, peerFetchResp.IgnoreLeaves, 2)
+
+	require.EqualValues(
+		t.t, rpcAsset.Amount,
+		peerFetchResp.IssuanceLeaves[0].LeafNode.RootSum,
+	)
+	require.EqualValues(
+		t.t, rpcAsset.Amount,
+		peerFetchResp.IgnoreSubtreeRoot.RootNode.RootSum,
+	)
 }
 
 // AssertInclusionProof checks that the inclusion proof for a given leaf key