Code simplifications

Co-authored-by: Daira Hopwood <[email protected]>

zcash_client_backend/src/data_api/scanning.rs

@@ -48,7 +48,7 @@ impl ScanRange {
 
     /// Returns whether or not the scan range is empty.
     pub fn is_empty(&self) -> bool {
-        self.block_range.end == self.block_range.start
+        self.block_range.is_empty()
     }
 
     /// Returns the number of blocks in the scan range.
@@ -89,20 +89,16 @@ impl ScanRange {
     /// end of the first range returned and the start of the second. Returns `None` if
     /// `p <= self.block_range().start || p >= self.block_range().end`.
     pub fn split_at(&self, p: BlockHeight) -> Option<(Self, Self)> {
-        if p > self.block_range.start && p < self.block_range.end {
-            Some((
-                ScanRange {
-                    block_range: self.block_range.start..p,
-                    priority: self.priority,
-                },
-                ScanRange {
-                    block_range: p..self.block_range.end,
-                    priority: self.priority,
-                },
-            ))
-        } else {
-            None
-        }
+        (p > self.block_range.start && p < self.block_range.end).then_some((
+            ScanRange {
+                block_range: self.block_range.start..p,
+                priority: self.priority,
+            },
+            ScanRange {
+                block_range: p..self.block_range.end,
+                priority: self.priority,
+            },
+        ))
     }
 }
 

zcash_client_sqlite/src/lib.rs

@@ -414,10 +414,10 @@ impl<P: consensus::Parameters> WalletWrite for WalletDb<rusqlite::Connection, P>
             });
             let mut wallet_note_ids = vec![];
             let mut sapling_commitments = vec![];
-            let mut end_height = None;
+            let mut last_scanned_height = None;
             let mut note_positions = vec![];
             for block in blocks.into_iter() {
-                if end_height.iter().any(|prev| block.height() != *prev + 1) {
+                if last_scanned_height.iter().any(|prev| block.height() != *prev + 1) {
                     return Err(SqliteClientError::NonSequentialBlocks);
                 }
 
@@ -453,14 +453,14 @@ impl<P: consensus::Parameters> WalletWrite for WalletDb<rusqlite::Connection, P>
                         .map(|out| out.note_commitment_tree_position())
                 }));
 
-                end_height = Some(block.height());
+                last_scanned_height = Some(block.height());
                 sapling_commitments.extend(block.into_sapling_commitments().into_iter());
             }
 
-            // We will have a start position and an end height in all cases where `blocks` is
-            // non-empty.
-            if let Some(((start_height, start_position), end_height)) =
-                start_positions.zip(end_height)
+            // We will have a start position and a last scanned height in all cases where
+            // `blocks` is non-empty.
+            if let Some(((start_height, start_position), last_scanned_height)) =
+                start_positions.zip(last_scanned_height)
             {
                 // Update the Sapling note commitment tree with all newly read note commitments
                 let mut sapling_commitments = sapling_commitments.into_iter();
@@ -470,14 +470,14 @@ impl<P: consensus::Parameters> WalletWrite for WalletDb<rusqlite::Connection, P>
                 })?;
 
                 // Update now-expired transactions that didn't get mined.
-                wallet::update_expired_notes(wdb.conn.0, end_height)?;
+                wallet::update_expired_notes(wdb.conn.0, last_scanned_height)?;
 
                 wallet::scanning::scan_complete(
                     wdb.conn.0,
                     &wdb.params,
                     Range {
                         start: start_height,
-                        end: end_height + 1,
+                        end: last_scanned_height + 1,
                     },
                     &note_positions,
                 )?;