Optimizing the code and making it more idiomatic (#2269)

core/src/consensus.rs

@@ -309,19 +309,13 @@ where
 
 /// Count, in units of 1/100 (a percent), the number of "secondary" (AR) blocks in the provided window of blocks.
 pub fn ar_count(_height: u64, diff_data: &[HeaderInfo]) -> u64 {
-	100 * diff_data
-		.iter()
-		.filter(|n| n.is_secondary)
-		.count() as u64
+	100 * diff_data.iter().filter(|n| n.is_secondary).count() as u64
 }
 
 /// Factor by which the secondary proof of work difficulty will be adjusted
 pub fn secondary_pow_scaling(height: u64, diff_data: &[HeaderInfo]) -> u32 {
 	// Get the scaling factor sum of the last DIFFICULTY_ADJUST_WINDOW elements
-	let scale_sum: u64 = diff_data
-		.iter()
-		.map(|dd| dd.secondary_scaling as u64)
-		.sum();
+	let scale_sum: u64 = diff_data.iter().map(|dd| dd.secondary_scaling as u64).sum();
 
 	// compute ideal 2nd_pow_fraction in pct and across window
 	let target_pct = secondary_pow_ratio(height);

core/src/core/block.rs

@@ -27,10 +27,7 @@ use crate::core::committed::{self, Committed};
 use crate::core::compact_block::{CompactBlock, CompactBlockBody};
 use crate::core::hash::{Hash, Hashed, ZERO_HASH};
 use crate::core::verifier_cache::VerifierCache;
-use crate::core::{
-	transaction, Commitment, Input, Output, Transaction,
-	TransactionBody, TxKernel,
-};
+use crate::core::{transaction, Commitment, Input, Output, Transaction, TransactionBody, TxKernel};
 use crate::global;
 use crate::keychain::{self, BlindingFactor};
 use crate::pow::{Difficulty, Proof, ProofOfWork};

core/src/core/pmmr/backend.rs

@@ -17,6 +17,7 @@ use croaring::Bitmap;
 use crate::core::hash::Hash;
 use crate::core::BlockHeader;
 use crate::ser::PMMRable;
+use std::path::Path;
 
 /// Storage backend for the MMR, just needs to be indexed by order of insertion.
 /// The PMMR itself does not need the Backend to be accurate on the existence
@@ -59,7 +60,7 @@ pub trait Backend<T: PMMRable> {
 	/// Returns the data file path.. this is a bit of a hack now that doesn't
 	/// sit well with the design, but TxKernels have to be summed and the
 	/// fastest way to to be able to allow direct access to the file
-	fn get_data_file_path(&self) -> &str;
+	fn get_data_file_path(&self) -> &Path;
 
 	/// Also a bit of a hack...
 	/// Saves a snapshot of the rewound utxo file with the block hash as

core/src/core/pmmr/pmmr.rs

@@ -22,6 +22,7 @@ use crate::core::merkle_proof::MerkleProof;
 use crate::core::pmmr::{Backend, ReadonlyPMMR};
 use crate::core::BlockHeader;
 use crate::ser::{PMMRIndexHashable, PMMRable};
+use std::path::Path;
 
 /// 64 bits all ones: 0b11111111...1
 const ALL_ONES: u64 = u64::MAX;
@@ -323,7 +324,7 @@ where
 	}
 
 	/// Return the path of the data file (needed to sum kernels efficiently)
-	pub fn data_file_path(&self) -> &str {
+	pub fn data_file_path(&self) -> &Path {
 		self.backend.get_data_file_path()
 	}
 

core/src/libtx/reward.rs

@@ -23,11 +23,7 @@ use crate::libtx::{aggsig, proof};
 use crate::util::static_secp_instance;
 
 /// output a reward output
-pub fn output<K>(
-	keychain: &K,
-	key_id: &Identifier,
-	fees: u64,
-) -> Result<(Output, TxKernel), Error>
+pub fn output<K>(keychain: &K, key_id: &Identifier, fees: u64) -> Result<(Output, TxKernel), Error>
 where
 	K: Keychain,
 {