fix(resharding): catchup shard even if not tracked for 1 epoch (near#…

…12756)

Follow up to [zulip
discussion](https://near.zulipchat.com/#narrow/channel/407288-core.2Fresharding/topic/forknet/near/494153325).

Hot fix to unblock resharding testing, until we have the proper fix in
place.

chain/chain/src/chain.rs

@@ -2465,12 +2465,12 @@ impl Chain {
     /// where we'll go from tracking it to not tracking it and back to tracking it in consecutive epochs,
     /// then we can just continue to apply chunks as if we were tracking it in epoch T, and there's no need to state sync.
     fn should_catch_up_shard(
-        epoch_manager: &dyn EpochManagerAdapter,
+        _epoch_manager: &dyn EpochManagerAdapter,
         shard_tracker: &ShardTracker,
         me: &Option<AccountId>,
         epoch_id: &EpochId,
         epoch_last_block: &CryptoHash,
-        epoch_last_block_prev: &CryptoHash,
+        _epoch_last_block_prev: &CryptoHash,
         shard_id: ShardId,
     ) -> Result<bool, Error> {
         // Won't care about it next epoch, no need to state sync it.
@@ -2488,19 +2488,20 @@ impl Chain {
             return Ok(true);
         }
 
-        let (_layout, parent_shard_id, _index) =
-            epoch_manager.get_prev_shard_id_from_prev_hash(epoch_last_block, shard_id)?;
-        // Note that here passing `epoch_last_block_prev` to care_about_shard() will have us check whether we were tracking it in
-        // the previous epoch, because it is the "parent_hash" of the last block of the previous epoch.
-        // TODO: consider refactoring these ShardTracker functions to accept an epoch_id
-        // to make this less tricky.
-        let tracked_before = shard_tracker.care_about_shard(
-            me.as_ref(),
-            epoch_last_block_prev,
-            parent_shard_id,
-            true,
-        );
-        Ok(!tracked_before)
+        // let (_layout, parent_shard_id, _index) =
+        //     epoch_manager.get_prev_shard_id_from_prev_hash(epoch_last_block, shard_id)?;
+        // // Note that here passing `epoch_last_block_prev` to care_about_shard() will have us check whether we were tracking it in
+        // // the previous epoch, because it is the "parent_hash" of the last block of the previous epoch.
+        // // TODO: consider refactoring these ShardTracker functions to accept an epoch_id
+        // // to make this less tricky.
+        // let tracked_before = shard_tracker.care_about_shard(
+        //     me.as_ref(),
+        //     epoch_last_block_prev,
+        //     parent_shard_id,
+        //     true,
+        // );
+        // TODO(resharding) Uncomment or remove above, and accordingly `_epoch_manager` and `_epoch_last_block_prev`.
+        Ok(true)
     }
 
     /// Check if any block with missing chunk is ready to be processed and start processing these blocks

integration-tests/src/test_loop/tests/resharding_v3.rs

@@ -49,9 +49,12 @@ const INCREASED_EPOCH_LENGTH: u64 = 10;
 const GC_NUM_EPOCHS_TO_KEEP: u64 = 3;
 
 /// Default number of epochs for resharding testloop to run.
-// TODO(resharding) Fix nearcore and set it to 10.
 const DEFAULT_TESTLOOP_NUM_EPOCHS_TO_WAIT: u64 = 8;
 
+/// Increased number of epochs for resharding testloop to run.
+/// To be used in tests with shard shuffling enabled, to cover more configurations of shard assignment.
+const INCREASED_TESTLOOP_NUM_EPOCHS_TO_WAIT: u64 = 12;
+
 /// Default shard layout version used in resharding tests.
 const DEFAULT_SHARD_LAYOUT_VERSION: u64 = 2;
 
@@ -832,6 +835,7 @@ fn test_resharding_v3_double_sign_resharding_block() {
 fn test_resharding_v3_shard_shuffling() {
     let params = TestReshardingParametersBuilder::default()
         .shuffle_shard_assignment_for_chunk_producers(true)
+        .num_epochs_to_wait(INCREASED_TESTLOOP_NUM_EPOCHS_TO_WAIT)
         .build();
     test_resharding_v3_base(params);
 }
@@ -854,15 +858,14 @@ fn test_resharding_v3_shard_shuffling_untrack_then_track() {
     let tracked_shard_sequence =
         vec![parent_shard_id, parent_shard_id, unrelated_shard_id, child_shard_id];
     let num_clients = 8;
-    let num_epochs_to_wait = DEFAULT_TESTLOOP_NUM_EPOCHS_TO_WAIT;
+    let num_epochs_to_wait = INCREASED_TESTLOOP_NUM_EPOCHS_TO_WAIT;
     let tracked_shard_schedule = TrackedShardSchedule {
         client_index: (num_clients - 1) as usize,
         schedule: shard_sequence_to_schedule(tracked_shard_sequence, num_epochs_to_wait),
     };
     let params = TestReshardingParametersBuilder::default()
-        // TODO(resharding): uncomment after the bug in the comment above get_should_apply_chunk()
-        // in chain.rs is fixed
-        //.shuffle_shard_assignment_for_chunk_producers(true)
+        .shuffle_shard_assignment_for_chunk_producers(true)
+        .num_epochs_to_wait(num_epochs_to_wait)
         .num_clients(num_clients)
         .tracked_shard_schedule(Some(tracked_shard_schedule.clone()))
         .add_loop_action(check_state_cleanup(tracked_shard_schedule, num_epochs_to_wait, true))
@@ -875,7 +878,7 @@ fn test_resharding_v3_shard_shuffling_intense() {
     let chunk_ranges_to_drop = HashMap::from([(0, -1..2), (1, -3..0), (2, -3..3), (3, 0..1)]);
     let params = TestReshardingParametersBuilder::default()
         .num_accounts(8)
-        .epoch_length(INCREASED_EPOCH_LENGTH)
+        .epoch_length(INCREASED_TESTLOOP_NUM_EPOCHS_TO_WAIT)
         .shuffle_shard_assignment_for_chunk_producers(true)
         .chunk_ranges_to_drop(chunk_ranges_to_drop)
         .add_loop_action(execute_money_transfers(
@@ -1103,6 +1106,7 @@ fn test_resharding_v3_slower_post_processing_tasks() {
 fn test_resharding_v3_shard_shuffling_slower_post_processing_tasks() {
     let params = TestReshardingParametersBuilder::default()
         .shuffle_shard_assignment_for_chunk_producers(true)
+        .num_epochs_to_wait(INCREASED_TESTLOOP_NUM_EPOCHS_TO_WAIT)
         .delay_flat_state_resharding(2)
         .epoch_length(INCREASED_EPOCH_LENGTH)
         .build();