Fast sync state error (#3261)

* Final commit to log and exit for fastSyncState.getPivotBlockHeader().get()

Signed-off-by: Sally MacFarlane <sally.macfarlane@consensys.net>
Signed-off-by: Swarnim Pratap Singh <swarnimpratap132@gmail.com>

Co-authored-by: Sally MacFarlane <sally.macfarlane@consensys.net>
Co-authored-by: Swarnim Pratap Singh <swarnim132@gmail.com>

ethereum/eth/src/main/java/org/hyperledger/besu/ethereum/eth/sync/fastsync/worldstate/FastWorldStateDownloader.java

@@ -107,6 +107,15 @@ public CompletableFuture<Void> run(
         return failed;
       }
 
+      Optional<BlockHeader> checkNull =
+          Optional.ofNullable(fastSyncState.getPivotBlockHeader().get());
+      if (checkNull.isEmpty()) {
+        LOG.error("Pivot Block not present");
+        final CompletableFuture<Void> failed = new CompletableFuture<>();
+        failed.completeExceptionally(new NullPointerException("Pivot Block not present"));
+        return failed;
+      }
+
       final BlockHeader header = fastSyncState.getPivotBlockHeader().get();
       final Hash stateRoot = header.getStateRoot();
       if (worldStateStorage.isWorldStateAvailable(stateRoot, header.getHash())) {