From dbd446788edb62da7cf272c24b053fc3ecd9fbe7 Mon Sep 17 00:00:00 2001
From: Adrian Sutton <adrian@symphonious.net>
Date: Thu, 14 Feb 2019 15:35:23 +1000
Subject: [PATCH] Fix NullPointerException - complete future with fast sync
 state not null. (#859)

---
 .../ethereum/eth/sync/fastsync/FastSyncActions.java        | 4 ++--
 .../ethereum/eth/sync/fastsync/FastSyncActionsTest.java    | 7 ++++---
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActions.java b/ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActions.java
index a52e1cfb1b..a6c37951f7 100644
--- a/ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActions.java
+++ b/ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActions.java
@@ -82,7 +82,7 @@ public CompletableFuture<FastSyncState> waitForSuitablePeers(final FastSyncState
                 if (ethContext.getEthPeers().availablePeerCount() > 0) {
                   LOG.warn(
                       "Fast sync timed out before minimum peer count was reached. Continuing with reduced peers.");
-                  result.complete(null);
+                  result.complete(fastSyncState);
                 } else {
                   LOG.warn(
                       "Maximum wait time for fast sync reached but no peers available. Continuing to wait for any available peer.");
@@ -98,7 +98,7 @@ public CompletableFuture<FastSyncState> waitForSuitablePeers(final FastSyncState
                 LOG.error("Failed to find peers for fast sync", error);
                 result.completeExceptionally(error);
               } else {
-                result.complete(null);
+                result.complete(fastSyncState);
               }
               return null;
             });
diff --git a/ethereum/eth/src/test/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActionsTest.java b/ethereum/eth/src/test/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActionsTest.java
index 635cca91c5..9c32065ab2 100644
--- a/ethereum/eth/src/test/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActionsTest.java
+++ b/ethereum/eth/src/test/java/tech/pegasys/pantheon/ethereum/eth/sync/fastsync/FastSyncActionsTest.java
@@ -93,14 +93,15 @@ public void waitForPeersShouldSucceedIfEnoughPeersAreFound() {
     }
     final CompletableFuture<FastSyncState> result =
         fastSyncActions.waitForSuitablePeers(EMPTY_SYNC_STATE);
-    assertThat(result).isCompleted();
+    assertThat(result).isCompletedWithValue(EMPTY_SYNC_STATE);
   }
 
   @Test
   public void waitForPeersShouldReportSuccessWhenTimeLimitReachedAndAPeerIsAvailable() {
     EthProtocolManagerTestUtil.createPeer(ethProtocolManager);
     timeoutCount.set(Integer.MAX_VALUE);
-    assertThat(fastSyncActions.waitForSuitablePeers(EMPTY_SYNC_STATE)).isCompleted();
+    assertThat(fastSyncActions.waitForSuitablePeers(EMPTY_SYNC_STATE))
+        .isCompletedWithValue(EMPTY_SYNC_STATE);
   }
 
   @Test
@@ -111,7 +112,7 @@ public void waitForPeersShouldContinueWaitingUntilAtLeastOnePeerIsAvailable() {
     assertThat(result).isNotCompleted();
 
     EthProtocolManagerTestUtil.createPeer(ethProtocolManager);
-    assertThat(result).isCompleted();
+    assertThat(result).isCompletedWithValue(EMPTY_SYNC_STATE);
   }
 
   @Test