fix(epoch config): Refactor validator assignment config (#12520)

This PR does not change the `EpochConfig` functionality, it just flatten
the `EpochConfig` struct.
Cetralize the epoch config contructors.

This PR is a precursor to the config overriedes on `EpochConfigs`.

chain/chain/src/runtime/mod.rs

@@ -1199,14 +1199,11 @@ impl RuntimeAdapter for NightshadeRuntime {
         genesis_config.protocol_upgrade_stake_threshold =
             epoch_config.protocol_upgrade_stake_threshold;
         genesis_config.shard_layout = epoch_config.shard_layout;
-        genesis_config.num_chunk_only_producer_seats =
-            epoch_config.validator_selection_config.num_chunk_only_producer_seats;
-        genesis_config.minimum_validators_per_shard =
-            epoch_config.validator_selection_config.minimum_validators_per_shard;
-        genesis_config.minimum_stake_ratio =
-            epoch_config.validator_selection_config.minimum_stake_ratio;
+        genesis_config.num_chunk_only_producer_seats = epoch_config.num_chunk_only_producer_seats;
+        genesis_config.minimum_validators_per_shard = epoch_config.minimum_validators_per_shard;
+        genesis_config.minimum_stake_ratio = epoch_config.minimum_stake_ratio;
         genesis_config.shuffle_shard_assignment_for_chunk_producers =
-            epoch_config.validator_selection_config.shuffle_shard_assignment_for_chunk_producers;
+            epoch_config.shuffle_shard_assignment_for_chunk_producers;
 
         let runtime_config =
             self.runtime_config_store.get_config(protocol_version).as_ref().clone();

chain/chain/src/test_utils/kv_runtime.rs

@@ -23,7 +23,6 @@ use near_primitives::epoch_block_info::BlockInfo;
 use near_primitives::epoch_info::EpochInfo;
 use near_primitives::epoch_manager::EpochConfig;
 use near_primitives::epoch_manager::ShardConfig;
-use near_primitives::epoch_manager::ValidatorSelectionConfig;
 use near_primitives::errors::{EpochError, InvalidTxError};
 use near_primitives::hash::{hash, CryptoHash};
 use near_primitives::receipt::{ActionReceipt, Receipt, ReceiptEnum, ReceiptV0};
@@ -55,7 +54,6 @@ use near_store::{
     TrieChanges, WrappedTrieChanges,
 };
 use near_vm_runner::{ContractCode, ContractRuntimeCache, NoContractRuntimeCache};
-use num_rational::Ratio;
 use std::cmp::Ordering;
 use std::collections::{BTreeMap, HashMap, HashSet};
 use std::sync::{Arc, RwLock};
@@ -496,24 +494,7 @@ impl EpochManagerAdapter for MockEpochManager {
     }
 
     fn get_epoch_config(&self, epoch_id: &EpochId) -> Result<EpochConfig, EpochError> {
-        Ok(EpochConfig {
-            epoch_length: self.epoch_length,
-            num_block_producer_seats: 2,
-            num_block_producer_seats_per_shard: vec![1, 1],
-            avg_hidden_validator_seats_per_shard: vec![1, 1],
-            block_producer_kickout_threshold: 0,
-            chunk_producer_kickout_threshold: 0,
-            chunk_validator_only_kickout_threshold: 0,
-            target_validator_mandates_per_shard: 1,
-            validator_max_kickout_stake_perc: 0,
-            online_min_threshold: Ratio::new(1i32, 4i32),
-            online_max_threshold: Ratio::new(3i32, 4i32),
-            fishermen_threshold: 1,
-            minimum_stake_divisor: 1,
-            protocol_upgrade_stake_threshold: Ratio::new(3i32, 4i32),
-            shard_layout: self.get_shard_layout(epoch_id).unwrap(),
-            validator_selection_config: ValidatorSelectionConfig::default(),
-        })
+        Ok(EpochConfig::mock(self.epoch_length, self.get_shard_layout(epoch_id).unwrap()))
     }
 
     /// Return the epoch info containing the mocked data.

chain/epoch-manager/src/shard_tracker.rs

@@ -252,7 +252,13 @@ mod tests {
             minimum_stake_divisor: 1,
             protocol_upgrade_stake_threshold: Ratio::new(80, 100),
             shard_layout: ShardLayout::multi_shard(num_shards, 0),
-            validator_selection_config: Default::default(),
+            num_chunk_producer_seats: 100,
+            num_chunk_validator_seats: 300,
+            num_chunk_only_producer_seats: 300,
+            minimum_validators_per_shard: 1,
+            minimum_stake_ratio: Ratio::new(160i32, 1_000_000i32),
+            chunk_producer_assignment_changes_limit: 5,
+            shuffle_shard_assignment_for_chunk_producers: false,
             validator_max_kickout_stake_perc: 100,
         };
         let reward_calculator = RewardCalculator {

chain/epoch-manager/src/test_utils.rs

@@ -13,7 +13,7 @@ use near_crypto::{KeyType, SecretKey};
 use near_primitives::challenge::SlashedValidator;
 use near_primitives::epoch_block_info::BlockInfoV2;
 use near_primitives::epoch_info::EpochInfo;
-use near_primitives::epoch_manager::{AllEpochConfig, EpochConfig, ValidatorSelectionConfig};
+use near_primitives::epoch_manager::{AllEpochConfig, EpochConfig};
 use near_primitives::hash::{hash, CryptoHash};
 use near_primitives::types::validator_stake::ValidatorStake;
 use near_primitives::types::{
@@ -151,10 +151,13 @@ pub fn epoch_config_with_production_config(
         online_max_threshold: Ratio::new(99, 100),
         protocol_upgrade_stake_threshold: Ratio::new(80, 100),
         minimum_stake_divisor: 1,
-        validator_selection_config: ValidatorSelectionConfig {
-            num_chunk_producer_seats,
-            ..Default::default()
-        },
+        num_chunk_producer_seats,
+        num_chunk_validator_seats: 300,
+        num_chunk_only_producer_seats: 300,
+        minimum_validators_per_shard: 1,
+        minimum_stake_ratio: Ratio::new(160i32, 1_000_000i32),
+        chunk_producer_assignment_changes_limit: 5,
+        shuffle_shard_assignment_for_chunk_producers: false,
         shard_layout: ShardLayout::multi_shard(num_shards, 0),
         validator_max_kickout_stake_perc: 100,
     };

chain/epoch-manager/src/tests/mod.rs

@@ -2336,7 +2336,13 @@ fn test_protocol_version_switch_with_many_seats() {
         protocol_upgrade_stake_threshold: Ratio::new(80, 100),
         minimum_stake_divisor: 1,
         shard_layout: ShardLayout::single_shard(),
-        validator_selection_config: Default::default(),
+        num_chunk_producer_seats: 100,
+        num_chunk_validator_seats: 300,
+        num_chunk_only_producer_seats: 300,
+        minimum_validators_per_shard: 1,
+        minimum_stake_ratio: Ratio::new(160i32, 1_000_000i32),
+        chunk_producer_assignment_changes_limit: 5,
+        shuffle_shard_assignment_for_chunk_producers: false,
         validator_max_kickout_stake_perc: 100,
     };
     let config = AllEpochConfig::new(false, PROTOCOL_VERSION, epoch_config, "test-chain");