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Co-authored-by: David Turner <[email protected]>

Author: JeremyDahlgren

server/src/internalClusterTest/java/org/elasticsearch/cluster/routing/allocation/decider/DiskThresholdDeciderIT.java

@@ -283,6 +283,7 @@ public void testRestoreSnapshotAllocationDoesNotExceedWatermarkWithMultipleResto
         final var useableSpaceShardSizes = shardSizes.getShardIdsWithSizeSmallerOrEqual(usableSpace);
         final var tinyNodeShardId = tinyNodeShardIds.isEmpty() == false
             ? tinyNodeShardIds.iterator().next()
+            // shardSizes only contains the sizes from the original index, not the copy, so we map the copied shard back to the original idx
             : new ShardId(useableSpaceShardSizes.iterator().next().getIndex(), tinyNodeShardIdsCopy.iterator().next().id());
         assertThat(tinyNodeShardId, in(useableSpaceShardSizes));
     }