Add BeaconChainHarness::builder (#2707)

## Issue Addressed

NA

## Proposed Changes

This PR is near-identical to https://github.com/sigp/lighthouse/pull/2652, however it is to be merged into `unstable` instead of `merge-f2f`. Please see that PR for reasoning.

I'm making this duplicate PR to merge to `unstable` in an effort to shrink the diff between `unstable` and `merge-f2f` by doing smaller, lead-up PRs.

## Additional Info

NA

consensus/fork_choice/tests/tests.rs

@@ -14,11 +14,10 @@ use fork_choice::{
     ForkChoiceStore, InvalidAttestation, InvalidBlock, QueuedAttestation,
     SAFE_SLOTS_TO_UPDATE_JUSTIFIED,
 };
-use store::{MemoryStore, StoreConfig};
+use store::MemoryStore;
 use types::{
-    test_utils::{generate_deterministic_keypair, generate_deterministic_keypairs},
-    BeaconBlock, BeaconBlockRef, BeaconState, Checkpoint, Epoch, EthSpec, Hash256,
-    IndexedAttestation, MainnetEthSpec, Slot, SubnetId,
+    test_utils::generate_deterministic_keypair, BeaconBlock, BeaconBlockRef, BeaconState,
+    Checkpoint, Epoch, EthSpec, Hash256, IndexedAttestation, MainnetEthSpec, Slot, SubnetId,
 };
 
 pub type E = MainnetEthSpec;
@@ -48,25 +47,23 @@ impl fmt::Debug for ForkChoiceTest {
 impl ForkChoiceTest {
     /// Creates a new tester.
     pub fn new() -> Self {
-        let harness = BeaconChainHarness::new_with_store_config(
-            MainnetEthSpec,
-            None,
-            generate_deterministic_keypairs(VALIDATOR_COUNT),
-            StoreConfig::default(),
-        );
+        let harness = BeaconChainHarness::builder(MainnetEthSpec)
+            .default_spec()
+            .deterministic_keypairs(VALIDATOR_COUNT)
+            .fresh_ephemeral_store()
+            .build();
 
         Self { harness }
     }
 
     /// Creates a new tester with a custom chain config.
     pub fn new_with_chain_config(chain_config: ChainConfig) -> Self {
-        let harness = BeaconChainHarness::new_with_chain_config(
-            MainnetEthSpec,
-            None,
-            generate_deterministic_keypairs(VALIDATOR_COUNT),
-            StoreConfig::default(),
-            chain_config,
-        );
+        let harness = BeaconChainHarness::builder(MainnetEthSpec)
+            .default_spec()
+            .chain_config(chain_config)
+            .deterministic_keypairs(VALIDATOR_COUNT)
+            .fresh_ephemeral_store()
+            .build();
 
         Self { harness }
     }

consensus/state_processing/src/per_block_processing/tests.rs

@@ -7,7 +7,6 @@ use crate::per_block_processing::errors::{
     ProposerSlashingInvalid,
 };
 use crate::{per_block_processing::process_operations, BlockSignatureStrategy, VerifySignatures};
-use beacon_chain::store::StoreConfig;
 use beacon_chain::test_utils::{BeaconChainHarness, EphemeralHarnessType};
 use lazy_static::lazy_static;
 use ssz_types::Bitfield;
@@ -32,12 +31,11 @@ fn get_harness<E: EthSpec>(
     // Set the state and block to be in the last slot of the `epoch_offset`th epoch.
     let last_slot_of_epoch =
         (MainnetEthSpec::genesis_epoch() + epoch_offset).end_slot(E::slots_per_epoch());
-    let harness = BeaconChainHarness::new_with_store_config(
-        E::default(),
-        None,
-        KEYPAIRS[0..num_validators].to_vec(),
-        StoreConfig::default(),
-    );
+    let harness = BeaconChainHarness::builder(E::default())
+        .default_spec()
+        .keypairs(KEYPAIRS[0..num_validators].to_vec())
+        .fresh_ephemeral_store()
+        .build();
     let state = harness.get_current_state();
     if last_slot_of_epoch > Slot::new(0) {
         harness.add_attested_blocks_at_slots(

consensus/state_processing/src/per_epoch_processing/tests.rs

@@ -1,6 +1,5 @@
 #![cfg(test)]
 use crate::per_epoch_processing::process_epoch;
-use beacon_chain::store::StoreConfig;
 use beacon_chain::test_utils::BeaconChainHarness;
 use beacon_chain::types::{EthSpec, MinimalEthSpec};
 use bls::Hash256;
@@ -11,12 +10,11 @@ use types::Slot;
 fn runs_without_error() {
     Builder::from_env(Env::default().default_filter_or("error")).init();
 
-    let harness = BeaconChainHarness::new_with_store_config(
-        MinimalEthSpec,
-        None,
-        types::test_utils::generate_deterministic_keypairs(8),
-        StoreConfig::default(),
-    );
+    let harness = BeaconChainHarness::builder(MinimalEthSpec)
+        .default_spec()
+        .deterministic_keypairs(8)
+        .fresh_ephemeral_store()
+        .build();
     harness.advance_slot();
 
     let spec = MinimalEthSpec::default_spec();
@@ -55,11 +53,11 @@ mod release_tests {
         spec.altair_fork_epoch = Some(Epoch::new(1));
 
         let altair_state = {
-            let harness = BeaconChainHarness::new(
-                MainnetEthSpec,
-                Some(spec.clone()),
-                types::test_utils::generate_deterministic_keypairs(8),
-            );
+            let harness = BeaconChainHarness::builder(MainnetEthSpec)
+                .spec(spec.clone())
+                .deterministic_keypairs(8)
+                .fresh_ephemeral_store()
+                .build();
 
             harness.advance_slot();
 
@@ -113,11 +111,11 @@ mod release_tests {
         spec.altair_fork_epoch = None;
 
         let base_state = {
-            let harness = BeaconChainHarness::new(
-                MainnetEthSpec,
-                Some(spec.clone()),
-                types::test_utils::generate_deterministic_keypairs(8),
-            );
+            let harness = BeaconChainHarness::builder(MainnetEthSpec)
+                .spec(spec.clone())
+                .deterministic_keypairs(8)
+                .fresh_ephemeral_store()
+                .build();
 
             harness.advance_slot();
 

consensus/tree_hash/examples/flamegraph_beacon_state.rs

@@ -1,4 +1,3 @@
-use beacon_chain::store::StoreConfig;
 use beacon_chain::test_utils::{BeaconChainHarness, EphemeralHarnessType};
 use types::{BeaconState, EthSpec, MainnetEthSpec};
 
@@ -6,12 +5,11 @@ const TREE_HASH_LOOPS: usize = 1_000;
 const VALIDATOR_COUNT: usize = 1_000;
 
 fn get_harness<T: EthSpec>() -> BeaconChainHarness<EphemeralHarnessType<T>> {
-    let harness = BeaconChainHarness::new_with_store_config(
-        T::default(),
-        None,
-        types::test_utils::generate_deterministic_keypairs(VALIDATOR_COUNT),
-        StoreConfig::default(),
-    );
+    let harness = BeaconChainHarness::builder(T::default())
+        .default_spec()
+        .deterministic_keypairs(VALIDATOR_COUNT)
+        .fresh_ephemeral_store()
+        .build();
 
     harness.advance_slot();
 

consensus/types/src/beacon_state/committee_cache/tests.rs

@@ -1,6 +1,5 @@
 #![cfg(test)]
 use crate::test_utils::*;
-use beacon_chain::store::StoreConfig;
 use beacon_chain::test_utils::{BeaconChainHarness, EphemeralHarnessType};
 use beacon_chain::types::*;
 use swap_or_not_shuffle::shuffle_list;
@@ -13,12 +12,11 @@ lazy_static! {
 }
 
 fn get_harness<E: EthSpec>(validator_count: usize) -> BeaconChainHarness<EphemeralHarnessType<E>> {
-    let harness = BeaconChainHarness::new_with_store_config(
-        E::default(),
-        None,
-        KEYPAIRS[0..validator_count].to_vec(),
-        StoreConfig::default(),
-    );
+    let harness = BeaconChainHarness::builder(E::default())
+        .default_spec()
+        .keypairs(KEYPAIRS[0..validator_count].to_vec())
+        .fresh_ephemeral_store()
+        .build();
     harness.advance_slot();
     harness
 }

consensus/types/src/beacon_state/tests.rs

@@ -1,7 +1,6 @@
 #![cfg(test)]
 use crate::test_utils::*;
 use crate::test_utils::{SeedableRng, XorShiftRng};
-use beacon_chain::store::config::StoreConfig;
 use beacon_chain::test_utils::{
     interop_genesis_state, test_spec, BeaconChainHarness, EphemeralHarnessType,
 };
@@ -29,12 +28,11 @@ fn get_harness<E: EthSpec>(
     validator_count: usize,
     slot: Slot,
 ) -> BeaconChainHarness<EphemeralHarnessType<E>> {
-    let harness = BeaconChainHarness::new_with_store_config(
-        E::default(),
-        None,
-        KEYPAIRS[0..validator_count].to_vec(),
-        StoreConfig::default(),
-    );
+    let harness = BeaconChainHarness::builder(E::default())
+        .default_spec()
+        .keypairs(KEYPAIRS[0..validator_count].to_vec())
+        .fresh_ephemeral_store()
+        .build();
 
     let skip_to_slot = slot - SLOT_OFFSET;
     if skip_to_slot > Slot::new(0) {