STAR-1364: fix RecoveryManagerTruncateTest::testTruncate (#700)

RecoveryManagerTruncateTest::testTruncate incorrectly expected commit log replay to replay some mutations.
The condition has been changed to expect no mutations being replayed for the keyspace in which the truncated table resides

Author: jakubzytka

test/unit/org/apache/cassandra/db/RecoveryManagerTruncateTest.java

@@ -22,6 +22,7 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.List;
 import java.util.Map;
 
 import org.junit.Before;
@@ -37,6 +38,7 @@
 import org.apache.cassandra.config.ParameterizedClass;
 import org.apache.cassandra.db.commitlog.CommitLog;
 import org.apache.cassandra.db.commitlog.CommitLogReplayer;
+import org.apache.cassandra.db.partitions.FilteredPartition;
 import org.apache.cassandra.db.partitions.PartitionUpdate;
 import org.apache.cassandra.exceptions.ConfigurationException;
 import org.apache.cassandra.io.compress.DeflateCompressor;
@@ -48,7 +50,7 @@
 import org.apache.cassandra.security.EncryptionContextGenerator;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -112,7 +114,8 @@ public void testTruncate() throws IOException
         // and now truncate it
         cfs.truncateBlocking();
         Map<Keyspace, Integer> replayed = CommitLog.instance.resetUnsafe(false);
-        assertFalse("Expected mutations to be replayed, but got " + replayed, replayed.isEmpty());
+        assertNull("Expected no mutations to be replayed for " + keyspace + " keyspace, but got " + replayed,
+                     replayed.get(keyspace));
 
         // and validate truncation.
         Util.assertEmptyUnfiltered(Util.cmd(cfs).build());