Merge pull request #699 from ethereum/start_shard_bug

fix committee assignment bugs
ethereum · Mar 3, 2019 · 146aef3 · 146aef3
2 parents d293b12 + dbbfb93
commit 146aef3
Showing 1 changed file with 8 additions and 5 deletions.
diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
@@ -877,19 +877,22 @@ def get_crosslink_committees_at_slot(state: BeaconState,
         shuffling_epoch = state.previous_shuffling_epoch
         shuffling_start_shard = state.previous_shuffling_start_shard
     elif epoch == next_epoch:
-        current_committees_per_epoch = get_current_epoch_committee_count(state)
-        committees_per_epoch = get_next_epoch_committee_count(state)
-        shuffling_epoch = next_epoch
-
         epochs_since_last_registry_update = current_epoch - state.validator_registry_update_epoch
         if registry_change:
+            committees_per_epoch = get_next_epoch_committee_count(state)
             seed = generate_seed(state, next_epoch)
+            shuffling_epoch = next_epoch
+            current_committees_per_epoch = get_current_epoch_committee_count(state)
             shuffling_start_shard = (state.current_shuffling_start_shard + current_committees_per_epoch) % SHARD_COUNT
         elif epochs_since_last_registry_update > 1 and is_power_of_two(epochs_since_last_registry_update):
+            committees_per_epoch = get_next_epoch_committee_count(state)
             seed = generate_seed(state, next_epoch)
+            shuffling_epoch = next_epoch
             shuffling_start_shard = state.current_shuffling_start_shard
         else:
+            committees_per_epoch = get_current_epoch_committee_count(state)
             seed = state.current_shuffling_seed
+            shuffling_epoch = state.current_shuffling_epoch
             shuffling_start_shard = state.current_shuffling_start_shard
 
     shuffling = get_shuffling(
@@ -2093,8 +2096,8 @@ def update_validator_registry(state: BeaconState) -> None:
 
 and perform the following updates:
 
-* Set `state.current_shuffling_epoch = next_epoch`
 * Set `state.current_shuffling_start_shard = (state.current_shuffling_start_shard + get_current_epoch_committee_count(state)) % SHARD_COUNT`
+* Set `state.current_shuffling_epoch = next_epoch`
 * Set `state.current_shuffling_seed = generate_seed(state, state.current_shuffling_epoch)`
 
 If a validator registry update does _not_ happen do the following: