asset+tapsend: add more debugging statements and helpers

To debug commitment issues, it's useful to log the exact asset leaf that
is committed. To be able to easily decode (and compare) that commitment,
we also add a unit test that outputs the leaf as JSON.

Author: guggero

asset/asset_test.go

@@ -4,6 +4,9 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"encoding/hex"
+	"encoding/json"
+	"os"
+	"path/filepath"
 	"reflect"
 	"testing"
 
@@ -106,6 +109,8 @@ var (
 			GroupPubKey: *pubKey,
 		},
 	}
+
+	assetHexFileName = filepath.Join("testdata", "asset.hex")
 )
 
 // TestGenesisAssetClassification tests that the multiple forms of genesis asset
@@ -1222,3 +1227,23 @@ func TestExternalKeyPubKey(t *testing.T) {
 		})
 	}
 }
+
+// TestDecodeAsset tests that we can decode an asset from a hex file. This is
+// mostly useful for debugging purposes.
+func TestDecodeAsset(t *testing.T) {
+	fileContent, err := os.ReadFile(assetHexFileName)
+	require.NoError(t, err)
+
+	assetBytes, err := hex.DecodeString(string(fileContent))
+	require.NoError(t, err)
+
+	var a Asset
+	err = a.Decode(bytes.NewReader(assetBytes))
+	require.NoError(t, err)
+
+	ta := NewTestFromAsset(t, &a)
+	assetJSON, err := json.MarshalIndent(ta, "", "\t")
+	require.NoError(t, err)
+
+	t.Logf("Decoded asset: %v", string(assetJSON))
+}

asset/testdata/asset.hex

@@ -0,0 +1 @@
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

tapsend/send.go

@@ -1584,6 +1584,9 @@ func LogCommitment(prefix string, idx int,
 		prefix, idx, tapCommitment.Version, merkleRoot[:],
 		internalKey.SerializeCompressed(), pkScript, trimmedMerkleRoot)
 	for _, a := range tapCommitment.CommittedAssets() {
+		var buf bytes.Buffer
+		_ = a.Encode(&buf)
+
 		groupKey := "<nil>"
 		if a.GroupKey != nil {
 			groupKey = hex.EncodeToString(
@@ -1592,9 +1595,11 @@ func LogCommitment(prefix string, idx int,
 		}
 		log.Tracef("%v commitment asset_id=%v, script_key=%x, "+
 			"group_key=%v, amount=%d, version=%d, "+
-			"split_commitment=%v", prefix, a.ID(),
+			"split_commitment=%v, encoded=%x", prefix, a.ID(),
 			a.ScriptKey.PubKey.SerializeCompressed(), groupKey,
-			a.Amount, a.Version, a.SplitCommitmentRoot != nil)
+			a.Amount, a.Version, a.SplitCommitmentRoot != nil,
+			buf.Bytes())
+
 	}
 }