From 46c0e176827be48cec31394391f0b981179adff4 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Fri, 21 Jun 2019 11:37:02 +1000
Subject: [PATCH] Add arbitrary attestation for beacon chain harness

---
 beacon_node/beacon_chain/src/beacon_chain.rs | 55 ++------------------
 beacon_node/beacon_chain/src/test_utils.rs   | 19 ++++---
 2 files changed, 18 insertions(+), 56 deletions(-)

diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index b8fff9611..235ec5f4c 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -425,65 +425,20 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
     }
 
     /// Produce an `AttestationData` that is valid for the present `slot` and given `shard`.
+    ///
+    /// Attests to the canonical chain.
     pub fn produce_attestation_data(&self, shard: u64) -> Result<AttestationData, Error> {
         let state = self.state.read();
         let head_block_root = self.head().beacon_block_root;
         let head_block_slot = self.head().beacon_block.slot;
 
         self.produce_attestation_data_for_block(shard, head_block_root, head_block_slot, &*state)
-        /*
-        let slots_per_epoch = T::EthSpec::slots_per_epoch();
-
-        self.metrics.attestation_production_requests.inc();
-        let timer = self.metrics.attestation_production_times.start_timer();
-
-        let state = self.state.read();
-
-        let current_epoch_start_slot = self
-            .state
-            .read()
-            .slot
-            .epoch(slots_per_epoch)
-            .start_slot(slots_per_epoch);
-
-        let target_root = if state.slot == current_epoch_start_slot {
-            // If we're on the first slot of the state's epoch.
-            if self.head().beacon_block.slot == state.slot {
-                // If the current head block is from the current slot, use its block root.
-                self.head().beacon_block_root
-            } else {
-                // If the current head block is not from this slot, use the slot from the previous
-                // epoch.
-                *self
-                    .state
-                    .read()
-                    .get_block_root(current_epoch_start_slot - slots_per_epoch)?
-            }
-        } else {
-            // If we're not on the first slot of the epoch.
-            *self.state.read().get_block_root(current_epoch_start_slot)?
-        };
-
-        let previous_crosslink_root =
-            Hash256::from_slice(&state.get_current_crosslink(shard)?.tree_hash_root());
-
-        self.metrics.attestation_production_successes.inc();
-        timer.observe_duration();
-
-        Ok(AttestationData {
-            beacon_block_root: self.head().beacon_block_root,
-            source_epoch: state.current_justified_epoch,
-            source_root: state.current_justified_root,
-            target_epoch: state.current_epoch(),
-            target_root,
-            shard,
-            previous_crosslink_root,
-            crosslink_data_root: Hash256::zero(),
-        })
-        */
     }
 
     /// Produce an `AttestationData` that attests to the chain denoted by `block_root` and `state`.
+    ///
+    /// Permits attesting to any arbitrary chain. Generally, the `produce_attestation_data`
+    /// function should be used as it attests to the canonical chain.
     pub fn produce_attestation_data_for_block(
         &self,
         shard: u64,
diff --git a/beacon_node/beacon_chain/src/test_utils.rs b/beacon_node/beacon_chain/src/test_utils.rs
index 8da68bbdc..b6873fa57 100644
--- a/beacon_node/beacon_chain/src/test_utils.rs
+++ b/beacon_node/beacon_chain/src/test_utils.rs
@@ -134,13 +134,11 @@ where
                 .expect("should not error during block processing");
 
             if let BlockProcessingOutcome::Processed { block_root } = outcome {
-                //
+                self.add_attestations_to_op_pool(&new_state, block_root, slot);
             } else {
                 panic!("block should be successfully processed");
             }
 
-            self.add_attestations_to_op_pool();
-
             state = new_state;
             slot += 1;
         }
@@ -198,8 +196,12 @@ where
         (block, state)
     }
 
-    fn add_attestations_to_op_pool(&self) {
-        let state = &self.chain.current_state();
+    fn add_attestations_to_op_pool(
+        &self,
+        state: &BeaconState<E>,
+        head_block_root: Hash256,
+        head_block_slot: Slot,
+    ) {
         let spec = &self.spec;
         let fork = &state.fork;
 
@@ -213,7 +215,12 @@ where
                 for (i, validator_index) in cc.committee.iter().enumerate() {
                     let data = self
                         .chain
-                        .produce_attestation_data(cc.shard)
+                        .produce_attestation_data_for_block(
+                            cc.shard,
+                            head_block_root,
+                            head_block_slot,
+                            state,
+                        )
                         .expect("should produce attestation data");
 
                     let mut aggregation_bitfield = Bitfield::new();