applied all requested changes from review

zebra-chain/src/block.rs

@@ -124,7 +124,7 @@ impl Block {
         network: &Network,
     ) -> Result<(), error::BlockError> {
         let block_nu =
-            NetworkUpgrade::current(&network, self.coinbase_height().expect("a valid height"));
+            NetworkUpgrade::current(network, self.coinbase_height().expect("a valid height"));
 
         if self
             .transactions

zebra-chain/src/block/arbitrary.rs

@@ -348,13 +348,14 @@ impl Arbitrary for Block {
     type Parameters = LedgerState;
 
     fn arbitrary_with(ledger_state: Self::Parameters) -> Self::Strategy {
-        let ledger_state_clone = ledger_state.clone();
-        let transactions_strategy =
+        let transactions_strategy = {
+            let ledger_state = ledger_state.clone();
             // Generate a random number transactions. A coinbase tx is always generated, so if
             // `transaction_count` is zero, the block will contain only the coinbase tx.
             (0..MAX_ARBITRARY_ITEMS).prop_flat_map(move |transaction_count| {
-                Transaction::vec_strategy(ledger_state_clone.clone(), transaction_count)
-            });
+                Transaction::vec_strategy(ledger_state.clone(), transaction_count)
+            })
+        };
 
         // TODO: if needed, fixup:
         // - history and authorizing data commitments

zebra-chain/src/block/commitment.rs

@@ -109,13 +109,13 @@ impl Commitment {
         use Commitment::*;
         use CommitmentError::*;
 
-        match NetworkUpgrade::current(&network, height) {
+        match NetworkUpgrade::current(network, height) {
             Genesis | BeforeOverwinter | Overwinter => Ok(PreSaplingReserved(bytes)),
             Sapling | Blossom => match sapling::tree::Root::try_from(bytes) {
                 Ok(root) => Ok(FinalSaplingRoot(root)),
                 _ => Err(InvalidSapingRootBytes),
             },
-            Heartwood if Some(height) == Heartwood.activation_height(&network) => {
+            Heartwood if Some(height) == Heartwood.activation_height(network) => {
                 if bytes == CHAIN_HISTORY_ACTIVATION_RESERVED {
                     Ok(ChainHistoryActivationReserved)
                 } else {

zebra-chain/src/history_tree.rs

@@ -83,7 +83,7 @@ impl NonEmptyHistoryTree {
         peaks: BTreeMap<u32, Entry>,
         current_height: Height,
     ) -> Result<Self, HistoryTreeError> {
-        let network_upgrade = NetworkUpgrade::current(&network, current_height);
+        let network_upgrade = NetworkUpgrade::current(network, current_height);
         let inner = match network_upgrade {
             NetworkUpgrade::Genesis
             | NetworkUpgrade::BeforeOverwinter
@@ -138,7 +138,7 @@ impl NonEmptyHistoryTree {
         let height = block
             .coinbase_height()
             .expect("block must have coinbase height during contextual verification");
-        let network_upgrade = NetworkUpgrade::current(&network, height);
+        let network_upgrade = NetworkUpgrade::current(network, height);
         let (tree, entry) = match network_upgrade {
             NetworkUpgrade::Genesis
             | NetworkUpgrade::BeforeOverwinter
@@ -239,8 +239,8 @@ impl NonEmptyHistoryTree {
 
     /// Extend the history tree with the given blocks.
     pub fn try_extend<
-        'b,
-        T: IntoIterator<Item = (Arc<Block>, &'b sapling::tree::Root, &'b orchard::tree::Root)>,
+        'a,
+        T: IntoIterator<Item = (Arc<Block>, &'a sapling::tree::Root, &'a orchard::tree::Root)>,
     >(
         &mut self,
         iter: T,
@@ -392,7 +392,7 @@ impl Clone for NonEmptyHistoryTree {
             ),
             InnerHistoryTree::OrchardOnward(_) => InnerHistoryTree::OrchardOnward(
                 Tree::<OrchardOnward>::new_from_cache(
-                    &self.network.clone(),
+                    &self.network,
                     self.network_upgrade,
                     self.size,
                     &self.peaks,
@@ -414,15 +414,9 @@ impl Clone for NonEmptyHistoryTree {
 
 /// A History Tree that keeps track of its own creation in the Heartwood
 /// activation block, being empty beforehand.
-#[derive(Debug, Default)]
+#[derive(Debug, Default, Clone)]
 pub struct HistoryTree(Option<NonEmptyHistoryTree>);
 
-impl Clone for HistoryTree {
-    fn clone(&self) -> Self {
-        HistoryTree(self.0.clone())
-    }
-}
-
 impl HistoryTree {
     /// Create a HistoryTree from a block.
     ///
@@ -435,7 +429,7 @@ impl HistoryTree {
         orchard_root: &orchard::tree::Root,
     ) -> Result<Self, HistoryTreeError> {
         let heartwood_height = NetworkUpgrade::Heartwood
-            .activation_height(&network)
+            .activation_height(network)
             .expect("Heartwood height is known");
         match block
             .coinbase_height()
@@ -444,8 +438,7 @@ impl HistoryTree {
         {
             std::cmp::Ordering::Less => Ok(HistoryTree(None)),
             _ => Ok(
-                NonEmptyHistoryTree::from_block(&network, block, sapling_root, orchard_root)?
-                    .into(),
+                NonEmptyHistoryTree::from_block(network, block, sapling_root, orchard_root)?.into(),
             ),
         }
     }
@@ -463,7 +456,7 @@ impl HistoryTree {
         orchard_root: &orchard::tree::Root,
     ) -> Result<(), HistoryTreeError> {
         let heartwood_height = NetworkUpgrade::Heartwood
-            .activation_height(&network)
+            .activation_height(network)
             .expect("Heartwood height is known");
         match block
             .coinbase_height()