Directory Restructure (#1163)

* Move tests -> testing

* Directory restructure

* Update Cargo.toml during restructure

* Update Makefile during restructure

* Fix arbitrary path

consensus/state_processing/src/common/get_attesting_indices.rs

@@ -0,0 +1,25 @@
+use types::*;
+
+/// Returns validator indices which participated in the attestation, sorted by increasing index.
+///
+/// Spec v0.11.1
+pub fn get_attesting_indices<T: EthSpec>(
+    committee: &[usize],
+    bitlist: &BitList<T::MaxValidatorsPerCommittee>,
+) -> Result<Vec<usize>, BeaconStateError> {
+    if bitlist.len() != committee.len() {
+        return Err(BeaconStateError::InvalidBitfield);
+    }
+
+    let mut indices = Vec::with_capacity(bitlist.num_set_bits());
+
+    for (i, validator_index) in committee.iter().enumerate() {
+        if let Ok(true) = bitlist.get(i) {
+            indices.push(*validator_index)
+        }
+    }
+
+    indices.sort_unstable();
+
+    Ok(indices)
+}