Add test for fetched tombstones metrics

Author: adelapena

test/unit/org/apache/cassandra/index/sai/metrics/QueryMetricsTest.java

@@ -494,6 +494,10 @@ private void testQueryKindMetrics(boolean perTable, boolean perQuery)
             for (int c = 0; c < numRowsPerPartition; c++)
                 execute("INSERT INTO %s (k, c, n, v) VALUES (?, ?, 1, [1, 1])", k, c);
 
+        // add a tombstone
+        execute("INSERT INTO %s (k, c, n, v) VALUES (?, ?, 1, [1, 1])", numPartitions, numRowsPerPartition);
+        execute("DELETE FROM %s WHERE k = ?", numPartitions);
+
         // filter query (goes to the general, filter and range query metrics)
         UntypedResultSet rows = execute("SELECT k, c FROM %s WHERE n = 1");
         assertEquals(numRows, rows.size());
@@ -530,13 +534,13 @@ private void testQueryKindMetrics(boolean perTable, boolean perQuery)
 
         // Verify counters for total keys fetched.
         name = "TotalKeysFetched";
-        waitForEquals(objectName(name, TABLE_QUERY_METRIC_TYPE), numRowsPerPartition + numRows + numRowsPerPartition + numRows + numRowsPerPartition + numRows);
+        waitForEquals(objectName(name, TABLE_QUERY_METRIC_TYPE), 3L * (numRowsPerPartition + numRows + 1));
         waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_FILTER_QUERY_METRIC_TYPE), numRowsPerPartition);
-        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_FILTER_QUERY_METRIC_TYPE), numRows);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_FILTER_QUERY_METRIC_TYPE), numRows + 1);
         waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_TOPK_QUERY_METRIC_TYPE), numRowsPerPartition);
-        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_TOPK_QUERY_METRIC_TYPE), numRows);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_TOPK_QUERY_METRIC_TYPE), numRows + 1);
         waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_HYBRID_QUERY_METRIC_TYPE), numRowsPerPartition);
-        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_HYBRID_QUERY_METRIC_TYPE), numRows);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_HYBRID_QUERY_METRIC_TYPE), numRows + 1);
 
         // Verify counters for total partitions fetched.
         name = "TotalPartitionsFetched";
@@ -578,6 +582,16 @@ private void testQueryKindMetrics(boolean perTable, boolean perQuery)
         waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_HYBRID_QUERY_METRIC_TYPE), numRowsPerPartition);
         waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_HYBRID_QUERY_METRIC_TYPE), numRows);
 
+        // Verify counters for total tombstones fetched.
+        name = "TotalTombstonesFetched";
+        waitForEquals(objectName(name, TABLE_QUERY_METRIC_TYPE), 3);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_FILTER_QUERY_METRIC_TYPE), 0);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_FILTER_QUERY_METRIC_TYPE), 1);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_TOPK_QUERY_METRIC_TYPE), 0);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_TOPK_QUERY_METRIC_TYPE), 1);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_SP_HYBRID_QUERY_METRIC_TYPE), 0);
+        waitForEqualsIfExists(perTable, objectName(name, TABLE_MP_HYBRID_QUERY_METRIC_TYPE), 1);
+
         // Verify counters for timeouts.
         name = "TotalQueryTimeouts";
         waitForEquals(objectName(name, TABLE_QUERY_METRIC_TYPE), 0);