Applies cleanup suggestions from code review

zebra-rpc/src/methods/get_block_template_rpcs/constants.rs

@@ -18,6 +18,8 @@ pub const GET_BLOCK_TEMPLATE_MEMPOOL_LONG_POLL_INTERVAL: u64 = 5;
 pub const GET_BLOCK_TEMPLATE_NONCE_RANGE_FIELD: &str = "00000000ffffffff";
 
 /// A hardcoded list of fields that the miner can change from the block template.
+///
+/// <https://en.bitcoin.it/wiki/BIP_0023#Mutations>
 pub const GET_BLOCK_TEMPLATE_MUTABLE_FIELD: &[&str] = &[
     // Standard mutations, copied from zcashd
     "time",
@@ -26,6 +28,8 @@ pub const GET_BLOCK_TEMPLATE_MUTABLE_FIELD: &[&str] = &[
 ];
 
 /// A hardcoded list of Zebra's getblocktemplate RPC capabilities.
+///
+/// <https://en.bitcoin.it/wiki/BIP_0023#Block_Proposal>
 pub const GET_BLOCK_TEMPLATE_CAPABILITIES_FIELD: &[&str] = &["proposal"];
 
 /// The max estimated distance to the chain tip for the getblocktemplate method.
@@ -34,6 +38,8 @@ pub const GET_BLOCK_TEMPLATE_CAPABILITIES_FIELD: &[&str] = &["proposal"];
 /// > A full validator MUST NOT accept blocks with nTime more than two hours in the future
 /// > according to its clock. This is not strictly a consensus rule because it is nondeterministic,
 /// > and clock time varies between nodes.
+/// >
+/// > <https://zips.z.cash/protocol/protocol.pdf#blockheader>
 pub const MAX_ESTIMATED_DISTANCE_TO_NETWORK_CHAIN_TIP: i32 = 100;
 
 /// The RPC error code used by `zcashd` for when it's still downloading initial blocks.

zebra-state/src/service.rs

@@ -1718,14 +1718,14 @@ impl Service<ReadRequest> for ReadStateService {
                         tracing::info!("attempting to validate and commit block proposal onto a cloned non-finalized state");
                         let mut latest_non_finalized_state = state.latest_non_finalized_state();
 
-                       // The previous block of a valid proposal must be on the best chain tip.
-                       let Some((_best_tip_height, best_tip_hash) = read::best_tip(&latest_non_finalized_state, &state.db) {
-                           if prepared.block.header.previous_block_hash !=  best_tip_hash {
-                               return Err("proposal is not based on the current best chain tip: previous block hash must be the best chain tip".into());
-                           }
-                       } else {
-                           return Err("state is empty: wait for Zebra to sync before submitting a proposal".into());
-                       }
+                        // The previous block of a valid proposal must be on the best chain tip.
+                        let Some((_best_tip_height, best_tip_hash)) = read::best_tip(&latest_non_finalized_state, &state.db) else {
+                            return Err("state is empty: wait for Zebra to sync before submitting a proposal".into());
+                        };
+
+                        if prepared.block.header.previous_block_hash != best_tip_hash {
+                            return Err("proposal is not based on the current best chain tip: previous block hash must be the best chain tip".into());
+                        }
 
                         // This clone of the non-finalized state is dropped when this closure returns.
                         // The non-finalized state that's used in the rest of the state (including finalizing

zebra-state/src/service/check.rs

@@ -14,13 +14,13 @@ use zebra_chain::{
 use crate::{
     service::{
         block_iter::any_ancestor_blocks, check::difficulty::POW_ADJUSTMENT_BLOCK_SPAN,
-        non_finalized_state::NonFinalizedState,
+        finalized_state::ZebraDb, non_finalized_state::NonFinalizedState,
     },
     BoxError, PreparedBlock, ValidateContextError,
 };
 
 // use self as check
-use super::{check, finalized_state::ZebraDb};
+use super::check;
 
 // These types are used in doc links
 #[allow(unused_imports)]

zebra-state/src/service/write.rs

@@ -12,7 +12,7 @@ use crate::{
     constants::MAX_BLOCK_REORG_HEIGHT,
     service::{
         check,
-        finalized_state::FinalizedState,
+        finalized_state::{FinalizedState, ZebraDb},
         non_finalized_state::NonFinalizedState,
         queued_blocks::{QueuedFinalized, QueuedNonFinalized},
         BoxError, ChainTipBlock, ChainTipSender, CloneError,
@@ -27,8 +27,6 @@ use crate::service::{
     non_finalized_state::Chain,
 };
 
-use super::finalized_state::ZebraDb;
-
 /// The maximum size of the parent error map.
 ///
 /// We allow enough space for multiple concurrent chain forks with errors.