state_processing: get_attesting_indices in common

eth2/state_processing/src/common/get_attesting_indices.rs

@@ -1,7 +1,22 @@
 use crate::common::verify_bitfield_length;
 use types::*;
 
-/// Returns validator indices which participated in the attestation.
+/// Returns validator indices which participated in the attestation, sorted by increasing index.
+///
+/// Spec v0.6.1
+pub fn get_attesting_indices<T: EthSpec>(
+    state: &BeaconState<T>,
+    attestation_data: &AttestationData,
+    bitfield: &Bitfield,
+) -> Result<Vec<usize>, BeaconStateError> {
+    get_attesting_indices_unsorted(state, attestation_data, bitfield).map(|mut indices| {
+        // Fast unstable sort is safe because validator indices are unique
+        indices.sort_unstable();
+        indices
+    })
+}
+
+/// Returns validator indices which participated in the attestation, unsorted.
 ///
 /// Spec v0.6.1
 pub fn get_attesting_indices_unsorted<T: EthSpec>(

eth2/state_processing/src/common/mod.rs

@@ -1,7 +1,9 @@
 mod exit;
+mod get_attesting_indices;
 mod slash_validator;
 mod verify_bitfield;
 
 pub use exit::initiate_validator_exit;
+pub use get_attesting_indices::{get_attesting_indices, get_attesting_indices_unsorted};
 pub use slash_validator::slash_validator;
 pub use verify_bitfield::verify_bitfield_length;

eth2/state_processing/src/per_epoch_processing.rs

@@ -10,7 +10,6 @@ use winning_root::{winning_root, WinningRoot};
 
 pub mod apply_rewards;
 pub mod errors;
-pub mod get_attesting_indices;
 pub mod inclusion_distance;
 pub mod process_slashings;
 pub mod registry_updates;

eth2/state_processing/src/per_epoch_processing/validator_statuses.rs

@@ -1,5 +1,5 @@
-use super::get_attesting_indices::get_attesting_indices_unsorted;
 use super::WinningRootHashSet;
+use crate::common::get_attesting_indices_unsorted;
 use types::*;
 
 /// Sets the boolean `var` on `self` to be true if it is true on `other`. Otherwise leaves `self`

eth2/state_processing/src/per_epoch_processing/winning_root.rs

@@ -1,4 +1,4 @@
-use super::get_attesting_indices::get_attesting_indices_unsorted;
+use crate::common::get_attesting_indices_unsorted;
 use std::collections::{HashMap, HashSet};
 use tree_hash::TreeHash;
 use types::*;