add comments

src/storage/src/hummock/event_handler/uploader.rs

@@ -1211,7 +1211,6 @@ mod tests {
     use crate::opts::StorageOpts;
     use crate::storage_value::StorageValue;
 
-    const BASIC_EPOCH: HummockEpoch = test_epoch(4);
     const INITIAL_EPOCH: HummockEpoch = test_epoch(5);
     const TEST_TABLE_ID: TableId = TableId { table_id: 233 };
 
@@ -1231,7 +1230,7 @@ mod tests {
     }
 
     fn initial_pinned_version() -> PinnedVersion {
-        PinnedVersion::new(test_hummock_version(BASIC_EPOCH), unbounded_channel().0)
+        PinnedVersion::new(test_hummock_version(INITIAL_EPOCH), unbounded_channel().0)
     }
 
     fn dummy_table_key() -> Vec<u8> {
@@ -1404,7 +1403,7 @@ mod tests {
     #[tokio::test]
     async fn test_uploader_basic() {
         let mut uploader = test_uploader(dummy_success_upload_future);
-        let epoch1 = INITIAL_EPOCH;
+        let epoch1 = INITIAL_EPOCH.next_epoch();
         let imm = gen_imm(epoch1).await;
         uploader.add_imm(imm.clone());
         assert_eq!(1, uploader.unsealed_data.len());

src/stream/tests/integration_tests/snapshot.rs

@@ -199,6 +199,8 @@ fn run_until_pending(
                 }
                 SnapshotEvent::Chunk(output)
             }
+            // The epoch value in the input is randomly chosen (e.g., 1, 2, 3), but during the actual processing, it undergoes a left shift.
+            // In order to ensure consistency between the input and output when comparing with the script, the epoch value in the output needs to be correspondingly right-shifted.
             Message::Barrier(barrier) => SnapshotEvent::Barrier(barrier.epoch.curr / test_epoch(1)),
             Message::Watermark(watermark) => SnapshotEvent::Watermark {
                 col_idx: watermark.col_idx,