fix

src/java/org/apache/cassandra/service/accord/CoordinatedTransfer.java

@@ -177,8 +177,8 @@ public class CoordinatedTransfer
 
     private void performImportTxn()
     {
+        Invariants.require(!streamResults.containsValue(SingleTransferResult.Init()));
         TimeUUID[] planIds = streamResults.values().stream()
-                                          .filter(result -> result.planId != null)
                                           .map(result -> result.planId)
                                           .toArray(TimeUUID[]::new);
 
@@ -284,9 +284,9 @@ public class CoordinatedTransfer
         if (state.hasFailedSession() || state.hasAbortedSession())
             throw new StreamException(state, "Stream failed due to failed or aborted sessions");
 
-        // If the SSTable doesn't contain any rows in the provided range, no streams delivered, nothing to activate
-        if (state.sessions().isEmpty())
-            return SingleTransferResult.Noop();
+        // Since we have filtered the SSTables using getPositionsForRanges prior, all sessions created
+        // should contain at least 1 SSTable
+        Invariants.require(!state.sessions().isEmpty());
 
         return SingleTransferResult.StreamComplete(plan.planId());
     }
@@ -392,7 +392,6 @@ public class CoordinatedTransfer
         enum State
         {
             INIT,
-            STREAM_NOOP,
             STREAM_FAILED,
             STREAM_COMPLETE;
         }
@@ -418,12 +417,6 @@ public class CoordinatedTransfer
             return new SingleTransferResult(State.STREAM_COMPLETE, planId);
         }
 
-        @VisibleForTesting
-        static SingleTransferResult Noop()
-        {
-            return new SingleTransferResult(State.STREAM_NOOP, null);
-        }
-
         public SingleTransferResult streamFailed(TimeUUID planId)
         {
             return new SingleTransferResult(State.STREAM_FAILED, planId);
@@ -434,6 +427,17 @@ public class CoordinatedTransfer
             return planId;
         }
 
+        @Override
+        public boolean equals(Object that)
+        {
+            return that instanceof SingleTransferResult && equals((SingleTransferResult) that);
+        }
+
+        public boolean equals(SingleTransferResult that)
+        {
+            return state == that.state && planId.equals(that.planId);
+        }
+
         @Override
         public String toString()
         {