TransactionBroadcast: add a unit test that verifies the rebroadcast functionality works.

core/src/test/java/com/google/bitcoin/core/TestWithPeerGroup.java

@@ -33,14 +33,18 @@ public class TestWithPeerGroup extends TestWithNetworkConnections {
     protected PeerGroup peerGroup;
 
     protected VersionMessage remoteVersionMessage;
+    private ClientBootstrap bootstrap;
 
     public void setUp(BlockStore blockStore) throws Exception {
         super.setUp(blockStore);
 
         remoteVersionMessage = new VersionMessage(unitTestParams, 1);
         remoteVersionMessage.clientVersion = FilteredBlock.MIN_PROTOCOL_VERSION;
-        
+        initPeerGroup();
-        ClientBootstrap bootstrap = new ClientBootstrap(new ChannelFactory() {
+    }
+
+    protected void initPeerGroup() {
+        bootstrap = new ClientBootstrap(new ChannelFactory() {
             public void releaseExternalResources() {}
             public Channel newChannel(ChannelPipeline pipeline) {
                 ChannelSink sink = new FakeChannelSink();
@@ -52,7 +56,7 @@ public class TestWithPeerGroup extends TestWithNetworkConnections {
             public ChannelPipeline getPipeline() throws Exception {
                 VersionMessage ver = new VersionMessage(unitTestParams, 1);
                 ChannelPipeline p = Channels.pipeline();
-                
+
                 Peer peer = new Peer(unitTestParams, blockChain, ver, peerGroup.getMemoryPool());
                 peer.addLifecycleListener(peerGroup.startupListener);
                 p.addLast("peer", peer.getHandler());
@@ -63,7 +67,7 @@ public class TestWithPeerGroup extends TestWithNetworkConnections {
         peerGroup = new PeerGroup(unitTestParams, blockChain, bootstrap);
         peerGroup.setPingIntervalMsec(0);  // Disable the pings as they just get in the way of most tests.
     }
-    
+
     protected FakeChannel connectPeer(int id) {
         return connectPeer(id, remoteVersionMessage);
     }

core/src/test/java/com/google/bitcoin/core/TransactionBroadcastTest.java

@@ -28,6 +28,7 @@ import java.util.Random;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
 
 public class TransactionBroadcastTest extends TestWithPeerGroup {
     @Override
@@ -67,6 +68,41 @@ public class TransactionBroadcastTest extends TestWithPeerGroup {
         assertTrue(future.isDone());
     }
 
+    @Test
+    public void retryFailedBroadcast() throws Exception {
+        // If we create a spend, it's sent to a peer that swallows it, and the peergroup is removed/re-added then
+        // the tx should be broadcast again.
+        FakeChannel p1 = connectPeer(1, new VersionMessage(params, 2));
+        connectPeer(2);
+
+        // Send ourselves a bit of money.
+        Block b1 = TestUtils.makeSolvedTestBlock(blockStore, address);
+        inbound(p1, b1);
+        assertNull(outbound(p1));
+        assertEquals(Utils.toNanoCoins(50, 0), wallet.getBalance());
+
+        // Now create a spend, and expect the announcement on p1.
+        Address dest = new ECKey().toAddress(params);
+        Wallet.SendResult sendResult = wallet.sendCoins(peerGroup, dest, Utils.toNanoCoins(1, 0));
+        assertFalse(sendResult.broadcastComplete.isDone());
+        Transaction t1 = (Transaction) outbound(p1);
+        assertFalse(sendResult.broadcastComplete.isDone());
+
+        // p1 eats it :( A bit later the PeerGroup is taken down.
+        peerGroup.removeWallet(wallet);
+        // ... and put back.
+        initPeerGroup();
+        peerGroup.addWallet(wallet);
+        p1 = connectPeer(1, new VersionMessage(params, 2));
+        connectPeer(2);
+
+        // We want to hear about it again. Now, because we've disabled the randomness for the unit tests it will
+        // re-appear on p1 again. Of course in the real world it would end up with a different set of peers and
+        // select randomly so we get a second chance.
+        Transaction t2 = (Transaction) outbound(p1);
+        assertEquals(t1, t2);
+    }
+
     @Test
     public void peerGroupWalletIntegration() throws Exception {
         // Make sure we can create spends, and that they are announced. Then do the same with offline mode.
@@ -79,7 +115,6 @@ public class TransactionBroadcastTest extends TestWithPeerGroup {
         Block b1 = TestUtils.makeSolvedTestBlock(blockStore, address);
         inbound(p1, b1);
         assertNull(outbound(p1));
-
         assertEquals(Utils.toNanoCoins(50, 0), wallet.getBalance());
 
         // Check that the wallet informs us of changes in confidence as the transaction ripples across the network.
@@ -98,7 +133,7 @@ public class TransactionBroadcastTest extends TestWithPeerGroup {
         Threading.waitForUserCode();
         assertFalse(sendResult.broadcastComplete.isDone());
         assertEquals(transactions[0], sendResult.tx);
-        assertEquals(transactions[0].getConfidence().numBroadcastPeers(), 0);
+        assertEquals(0, transactions[0].getConfidence().numBroadcastPeers());
         transactions[0] = null;
         Transaction t1 = (Transaction) outbound(p1);
         assertNotNull(t1);