Ensure ElectrumClient is disposed after sync

bdk_demo/lib/main.dart

@@ -101,24 +101,24 @@ class _MyHomePageState extends State<MyHomePage> {
               _error != null
                   ? Icons.error_outline
                   : _networkName != null
-                  ? Icons.check_circle
-                  : Icons.network_check,
+                      ? Icons.check_circle
+                      : Icons.network_check,
               size: 80,
               color: _error != null
                   ? Colors.red
                   : _networkName != null
-                  ? Colors.green
-                  : Colors.grey,
+                      ? Colors.green
+                      : Colors.grey,
             ),
             const SizedBox(height: 20),
             const Text('BDK bindings status', style: TextStyle(fontSize: 20)),
             if (_networkName != null) ...[
               Text(
                 'Network: $_networkName',
                 style: Theme.of(context).textTheme.headlineMedium?.copyWith(
-                  color: Colors.orange,
-                  fontWeight: FontWeight.bold,
-                ),
+                      color: Colors.orange,
+                      fontWeight: FontWeight.bold,
+                    ),
               ),
               if (_descriptorSnippet != null)
                 Padding(

examples/network_example.dart

@@ -16,33 +16,45 @@ void main() {
 
   // 2. Turn the mnemonic into descriptor keys for external/change paths.
   final rootKey = DescriptorSecretKey(network, mnemonic, null);
-  final externalDescriptor =
-      Descriptor.newBip84(rootKey, KeychainKind.external_, network);
-  final changeDescriptor =
-      Descriptor.newBip84(rootKey, KeychainKind.internal, network);
+  final externalDescriptor = Descriptor.newBip84(
+    rootKey,
+    KeychainKind.external_,
+    network,
+  );
+  final changeDescriptor = Descriptor.newBip84(
+    rootKey,
+    KeychainKind.internal,
+    network,
+  );
 
   stdout
     ..writeln('\nExternal descriptor:\n  $externalDescriptor')
     ..writeln('Change descriptor:\n  $changeDescriptor');
 
   // 3. Spin up an in-memory wallet using the descriptors.
   final persister = Persister.newInMemory();
-  final wallet =
-      Wallet(externalDescriptor, changeDescriptor, network, persister, 25);
+  final wallet = Wallet(
+    externalDescriptor,
+    changeDescriptor,
+    network,
+    persister,
+    25,
+  );
   stdout.writeln('\nWallet ready on ${wallet.network()}');
 
   // 4. Hand out the next receive address and persist the staged change.
   final receive = wallet.revealNextAddress(KeychainKind.external_);
   stdout.writeln(
-      'Next receive address (#${receive.index}): ${receive.address.toString()}');
+    'Next receive address (#${receive.index}): ${receive.address.toString()}',
+  );
   final persisted = wallet.persist(persister);
   stdout.writeln('Persisted staged wallet changes: $persisted');
 
   // 5. Try a quick Electrum sync to fetch history/balances.
+  ElectrumClient? client;
   try {
     stdout.writeln('\nSyncing via Electrum (blockstream.info)…');
-    final client =
-        ElectrumClient('ssl://electrum.blockstream.info:60002', null);
+    client = ElectrumClient('ssl://electrum.blockstream.info:60002', null);
     final syncRequest = wallet.startSyncWithRevealedSpks().build();
     final update = client.sync_(syncRequest, 100, true);
 
@@ -52,13 +64,13 @@ void main() {
     final balance = wallet.balance();
     stdout.writeln('Confirmed balance: ${balance.confirmed.toSat()} sats');
     stdout.writeln('Total balance: ${balance.total.toSat()} sats');
-
-    client.dispose();
   } catch (error) {
     stdout.writeln(
       'Electrum sync failed: $error\n'
       'Ensure TLS-enabled Electrum access is available, or skip this step.',
     );
+  } finally {
+    client?.dispose();
   }
 
   // 6. Clean up FFI handles explicitly so long-lived examples don’t leak.

test/descriptor_test.dart

@@ -6,49 +6,19 @@ import 'test_constants.dart';
 void main() {
   group('Descriptor construction', () {
     test('creates extended WPKH descriptors across networks', () {
-      expect(
-        () => buildBip84Descriptor(Network.regtest),
-        returnsNormally,
-      );
-      expect(
-        () => buildBip84Descriptor(Network.testnet),
-        returnsNormally,
-      );
-      expect(
-        () => buildBip84Descriptor(Network.testnet4),
-        returnsNormally,
-      );
-      expect(
-        () => buildBip84Descriptor(Network.signet),
-        returnsNormally,
-      );
-      expect(
-        () => buildMainnetBip84Descriptor(),
-        returnsNormally,
-      );
+      expect(() => buildBip84Descriptor(Network.regtest), returnsNormally);
+      expect(() => buildBip84Descriptor(Network.testnet), returnsNormally);
+      expect(() => buildBip84Descriptor(Network.testnet4), returnsNormally);
+      expect(() => buildBip84Descriptor(Network.signet), returnsNormally);
+      expect(() => buildMainnetBip84Descriptor(), returnsNormally);
     });
 
     test('creates extended TR descriptors across networks', () {
-      expect(
-        () => buildBip86Descriptor(Network.regtest),
-        returnsNormally,
-      );
-      expect(
-        () => buildBip86Descriptor(Network.testnet),
-        returnsNormally,
-      );
-      expect(
-        () => buildBip86Descriptor(Network.testnet4),
-        returnsNormally,
-      );
-      expect(
-        () => buildBip86Descriptor(Network.signet),
-        returnsNormally,
-      );
-      expect(
-        () => buildMainnetBip86Descriptor(),
-        returnsNormally,
-      );
+      expect(() => buildBip86Descriptor(Network.regtest), returnsNormally);
+      expect(() => buildBip86Descriptor(Network.testnet), returnsNormally);
+      expect(() => buildBip86Descriptor(Network.testnet4), returnsNormally);
+      expect(() => buildBip86Descriptor(Network.signet), returnsNormally);
+      expect(() => buildMainnetBip86Descriptor(), returnsNormally);
     });
 
     test('creates non-extended descriptors for all networks', () {

test/offline_persistence_test.dart

@@ -44,7 +44,9 @@ void main() {
       final wallet = Wallet.load(
         buildDescriptor(persistencePublicDescriptorString, Network.signet),
         buildDescriptor(
-            persistencePublicChangeDescriptorString, Network.signet),
+          persistencePublicChangeDescriptorString,
+          Network.signet,
+        ),
         persister,
         defaultLookahead,
       );

test/offline_wallet_test.dart

@@ -6,10 +6,14 @@ import 'test_constants.dart';
 void main() {
   group('Offline wallet', () {
     test('revealNextAddress yields expected address on multiple networks', () {
-      final descriptor =
-          buildDescriptor(offlineDescriptorString, Network.signet);
-      final changeDescriptor =
-          buildDescriptor(offlineChangeDescriptorString, Network.signet);
+      final descriptor = buildDescriptor(
+        offlineDescriptorString,
+        Network.signet,
+      );
+      final changeDescriptor = buildDescriptor(
+        offlineChangeDescriptorString,
+        Network.signet,
+      );
       final persister = Persister.newInMemory();
       final wallet = Wallet(
         descriptor,
@@ -34,10 +38,14 @@ void main() {
     });
 
     test('new wallet starts with zero balance', () {
-      final descriptor =
-          buildDescriptor(offlineDescriptorString, Network.signet);
-      final changeDescriptor =
-          buildDescriptor(offlineChangeDescriptorString, Network.signet);
+      final descriptor = buildDescriptor(
+        offlineDescriptorString,
+        Network.signet,
+      );
+      final changeDescriptor = buildDescriptor(
+        offlineChangeDescriptorString,
+        Network.signet,
+      );
       final persister = Persister.newInMemory();
       final wallet = Wallet(
         descriptor,

test/test_constants.dart

@@ -37,25 +37,17 @@ const expectedPersistedAddress = "tb1qan3lldunh37ma6c0afeywgjyjgnyc8uz975zl2";
 Descriptor buildDescriptor(String descriptor, Network network) =>
     Descriptor(descriptor, network);
 
-Descriptor buildBip84Descriptor(Network network) => Descriptor(
-      "wpkh($testExtendedPrivKey/$bip84TestReceivePath/*)",
-      network,
-    );
+Descriptor buildBip84Descriptor(Network network) =>
+    Descriptor("wpkh($testExtendedPrivKey/$bip84TestReceivePath/*)", network);
 
-Descriptor buildBip84ChangeDescriptor(Network network) => Descriptor(
-      "wpkh($testExtendedPrivKey/$bip84TestChangePath/*)",
-      network,
-    );
+Descriptor buildBip84ChangeDescriptor(Network network) =>
+    Descriptor("wpkh($testExtendedPrivKey/$bip84TestChangePath/*)", network);
 
-Descriptor buildBip86Descriptor(Network network) => Descriptor(
-      "tr($testExtendedPrivKey/$bip86TestReceivePath/*)",
-      network,
-    );
+Descriptor buildBip86Descriptor(Network network) =>
+    Descriptor("tr($testExtendedPrivKey/$bip86TestReceivePath/*)", network);
 
-Descriptor buildBip86ChangeDescriptor(Network network) => Descriptor(
-      "tr($testExtendedPrivKey/$bip86TestChangePath/*)",
-      network,
-    );
+Descriptor buildBip86ChangeDescriptor(Network network) =>
+    Descriptor("tr($testExtendedPrivKey/$bip86TestChangePath/*)", network);
 
 Descriptor buildMainnetBip84Descriptor() => Descriptor(
       "wpkh($mainnetExtendedPrivKey/$bip84MainnetReceivePath/*)",

test/wallet_behavior_test.dart

@@ -33,23 +33,24 @@ void main() {
     });
 
     test(
-        'single-descriptor wallet returns identical external/internal addresses',
-        () {
-      final persister = Persister.newInMemory();
-      final wallet = Wallet.createSingle(
-        buildBip84Descriptor(Network.testnet),
-        Network.testnet,
-        persister,
-        defaultLookahead,
-      );
-
-      final externalAddress = wallet.peekAddress(KeychainKind.external_, 0);
-      final internalAddress = wallet.peekAddress(KeychainKind.internal, 0);
-
-      expect(
-        externalAddress.address.scriptPubkey().toBytes(),
-        orderedEquals(internalAddress.address.scriptPubkey().toBytes()),
-      );
-    });
+      'single-descriptor wallet returns identical external/internal addresses',
+      () {
+        final persister = Persister.newInMemory();
+        final wallet = Wallet.createSingle(
+          buildBip84Descriptor(Network.testnet),
+          Network.testnet,
+          persister,
+          defaultLookahead,
+        );
+
+        final externalAddress = wallet.peekAddress(KeychainKind.external_, 0);
+        final internalAddress = wallet.peekAddress(KeychainKind.internal, 0);
+
+        expect(
+          externalAddress.address.scriptPubkey().toBytes(),
+          orderedEquals(internalAddress.address.scriptPubkey().toBytes()),
+        );
+      },
+    );
   });
 }

test/wallet_creation_test.dart

@@ -3,10 +3,7 @@ import 'package:test/test.dart';
 
 import 'test_constants.dart';
 
-Wallet _createWallet(
-  Descriptor descriptor,
-  Descriptor changeDescriptor,
-) {
+Wallet _createWallet(Descriptor descriptor, Descriptor changeDescriptor) {
   final persister = Persister.newInMemory();
   return Wallet(
     descriptor,
@@ -77,10 +74,8 @@ void main() {
 
     test('fails for private multipath descriptor', () {
       expect(
-        () => buildDescriptor(
-          privateMultipathDescriptorString,
-          Network.testnet,
-        ),
+        () =>
+            buildDescriptor(privateMultipathDescriptorString, Network.testnet),
         throwsA(isA<DescriptorException>()),
       );
     });