test: add zero_value_anchor_test.go

Add the missing integration test for zero-value UTXO sweeping functionality.

Author: darioAnongba

itest/zero_value_anchor_test.go

@@ -0,0 +1,116 @@
+package itest
+
+import (
+	"context"
+
+	"github.com/lightninglabs/taproot-assets/taprpc"
+	"github.com/lightninglabs/taproot-assets/taprpc/mintrpc"
+	"github.com/stretchr/testify/require"
+)
+
+// testZeroValueAnchorSweep tests that zero-value anchor outputs (tombstones)
+// are automatically swept when creating new on-chain transactions.
+func testZeroValueAnchorSweep(t *harnessTest) {
+	ctxb := context.Background()
+
+	// First, mint some simple assets.
+	rpcAssets := MintAssetsConfirmBatch(
+		t.t, t.lndHarness.Miner().Client, t.tapd,
+		[]*mintrpc.MintAssetRequest{simpleAssets[0]},
+	)
+
+	genInfo := rpcAssets[0].AssetGenesis
+	assetAmount := simpleAssets[0].Asset.Amount
+
+	// Create a second tapd node.
+	bobLnd := t.lndHarness.NewNodeWithCoins("Bob", nil)
+	secondTapd := setupTapdHarness(t.t, t, bobLnd, t.universeServer)
+	defer func() {
+		require.NoError(t.t, secondTapd.stop(!*noDelete))
+	}()
+
+	// Create an address for Bob to receive ALL assets (full value send).
+	// This should create a tombstone output on Alice's side.
+	bobAddr, err := secondTapd.NewAddr(ctxb, &taprpc.NewAddrRequest{
+		AssetId:      genInfo.AssetId,
+		Amt:          assetAmount, // Send ALL
+		AssetVersion: rpcAssets[0].Version,
+	})
+	require.NoError(t.t, err)
+
+	// Send ALL assets to Bob, which should create a tombstone output.
+	sendResp, _ := sendAssetsToAddr(t, t.tapd, bobAddr)
+
+	// Confirm the send and wait for completion.
+	ConfirmAndAssertOutboundTransfer(
+		t.t, t.lndHarness.Miner().Client, t.tapd, sendResp,
+		genInfo.AssetId,
+		[]uint64{0, assetAmount}, 0, 1,
+	)
+	AssertNonInteractiveRecvComplete(t.t, secondTapd, 1)
+
+	// At this point, Alice should have a tombstone UTXO.
+	// Check Alice's UTXOs to see if there are any without assets (tombstones).
+	aliceUtxos, err := t.tapd.ListUtxos(ctxb, &taprpc.ListUtxosRequest{})
+	require.NoError(t.t, err)
+
+	tombstoneCount := 0
+	for _, utxo := range aliceUtxos.ManagedUtxos {
+		if len(utxo.Assets) == 0 {
+			tombstoneCount++
+			t.t.Logf("Found tombstone UTXO: %s, value=%d",
+				utxo.OutPoint, utxo.AmtSat)
+		}
+	}
+
+	t.t.Logf("Alice has %d tombstone UTXOs before sweep", tombstoneCount)
+	require.Greater(t.t, tombstoneCount, 0, "Should have at least one tombstone UTXO")
+
+	// Now mint more assets for Alice so she can create another transaction
+	// that should sweep the tombstones.
+	rpcAssets2 := MintAssetsConfirmBatch(
+		t.t, t.lndHarness.Miner().Client, t.tapd,
+		[]*mintrpc.MintAssetRequest{simpleAssets[1]},
+	)
+
+	genInfo2 := rpcAssets2[0].AssetGenesis
+	assetAmount2 := simpleAssets[1].Asset.Amount
+
+	// Create another address for Bob.
+	bobAddr2, err := secondTapd.NewAddr(ctxb, &taprpc.NewAddrRequest{
+		AssetId:      genInfo2.AssetId,
+		Amt:          assetAmount2,
+		AssetVersion: rpcAssets2[0].Version,
+	})
+	require.NoError(t.t, err)
+
+	// Send the new assets. This should sweep Alice's tombstone UTXOs.
+	sendResp2, _ := sendAssetsToAddr(t, t.tapd, bobAddr2)
+
+	// Confirm the send.
+	ConfirmAndAssertOutboundTransfer(
+		t.t, t.lndHarness.Miner().Client, t.tapd, sendResp2,
+		genInfo2.AssetId,
+		[]uint64{0, assetAmount2}, 1, 2,
+	)
+	AssertNonInteractiveRecvComplete(t.t, secondTapd, 2)
+
+	// Check Alice's UTXOs again. The tombstones should have been swept.
+	finalAliceUtxos, err := t.tapd.ListUtxos(ctxb, &taprpc.ListUtxosRequest{})
+	require.NoError(t.t, err)
+
+	finalTombstoneCount := 0
+	for _, utxo := range finalAliceUtxos.ManagedUtxos {
+		if len(utxo.Assets) == 0 {
+			finalTombstoneCount++
+			t.t.Logf("Found tombstone UTXO after sweep: %s, value=%d",
+				utxo.OutPoint, utxo.AmtSat)
+		}
+	}
+
+	t.t.Logf("Alice has %d tombstone UTXOs after sweep", finalTombstoneCount)
+
+	// We expect no tombstones after the sweep transaction.
+	require.Equal(t.t, 0, finalTombstoneCount,
+		"All tombstones should be swept")
+}