Fix string to empty string comparison and len zero warnings

Signed-off-by: Jacinta Ferrant <[email protected]>

Author: jferrant

stackslib/src/burnchains/affirmation.rs

@@ -378,6 +378,10 @@ impl AffirmationMap {
         self.affirmations.len()
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.affirmations.is_empty()
+    }
+
     pub fn as_slice(&self) -> &[AffirmationMapEntry] {
         &self.affirmations
     }
@@ -876,7 +880,7 @@ fn inner_find_heaviest_block_commit_ptr(
     test_debug!("ancestors = {:?}", &ancestors);
     test_debug!("ancestor_confirmations = {:?}", &ancestor_confirmations);
 
-    if ancestor_confirmations.len() == 0 {
+    if ancestor_confirmations.is_empty() {
         // empty prepare phase
         test_debug!("Prepare-phase has no block-commits");
         return None;

stackslib/src/burnchains/bitcoin/address.rs

@@ -317,7 +317,7 @@ impl SegwitBitcoinAddress {
             None
         }?;
 
-        if quintets.len() == 0 || quintets.len() > 65 {
+        if quintets.is_empty() || quintets.len() > 65 {
             test_debug!("Invalid prog length: {}", quintets.len());
             return None;
         }

stackslib/src/burnchains/bitcoin/bits.rs

@@ -93,7 +93,7 @@ impl BitcoinTxInputStructured {
         segwit: bool,
         input_txid: (Txid, u32),
     ) -> Option<BitcoinTxInputStructured> {
-        if num_sigs < 1 || pubkey_pushbytes.len() < 1 || pubkey_pushbytes.len() < num_sigs {
+        if num_sigs < 1 || pubkey_pushbytes.is_empty() || pubkey_pushbytes.len() < num_sigs {
             test_debug!(
                 "Not a multisig script: num_sigs = {}, num_pubkeys <= {}",
                 num_sigs,
@@ -153,7 +153,7 @@ impl BitcoinTxInputStructured {
         pubkey_vecs: &[Vec<u8>],
         input_txid: (Txid, u32),
     ) -> Option<BitcoinTxInputStructured> {
-        if num_sigs < 1 || pubkey_vecs.len() < 1 || pubkey_vecs.len() < num_sigs {
+        if num_sigs < 1 || pubkey_vecs.is_empty() || pubkey_vecs.len() < num_sigs {
             test_debug!(
                 "Not a multisig script: num_sigs = {}, num_pubkeys <= {}",
                 num_sigs,

stackslib/src/burnchains/bitcoin/blocks.rs

@@ -381,7 +381,7 @@ impl BitcoinBlockParser {
         tx: &Transaction,
         epoch_id: StacksEpochId,
     ) -> Option<Vec<BitcoinTxOutput>> {
-        if tx.output.len() == 0 {
+        if tx.output.is_empty() {
             return None;
         }
 

stackslib/src/burnchains/bitcoin/indexer.rs

@@ -705,7 +705,7 @@ impl BitcoinIndexer {
                     e
                 })?;
 
-            if reorg_headers.len() == 0 {
+            if reorg_headers.is_empty() {
                 // chain shrank considerably
                 info!(
                     "Missing Bitcoin headers in block range {}-{} -- did the Bitcoin chain shrink?",
@@ -736,7 +736,7 @@ impl BitcoinIndexer {
                 })?;
 
             assert!(
-                canonical_headers.len() > 0,
+                !canonical_headers.is_empty(),
                 "BUG: uninitialized canonical SPV headers DB"
             );
 
@@ -1379,7 +1379,7 @@ mod test {
                         spv_client
                             .insert_block_headers_before(start_block - 1, hdrs)
                             .unwrap();
-                    } else if hdrs.len() > 0 {
+                    } else if !hdrs.is_empty() {
                         test_debug!("insert at {}: {:?}", 0, &hdrs);
                         spv_client.test_write_block_headers(0, hdrs).unwrap();
                     }
@@ -1552,7 +1552,7 @@ mod test {
                         spv_client
                             .insert_block_headers_before(start_block - 1, hdrs)
                             .unwrap();
-                    } else if hdrs.len() > 0 {
+                    } else if !hdrs.is_empty() {
                         test_debug!("insert at {}: {:?}", 0, &hdrs);
                         spv_client.test_write_block_headers(0, hdrs).unwrap();
                     }

stackslib/src/burnchains/bitcoin/network.rs

@@ -355,7 +355,7 @@ impl BitcoinIndexer {
 
     /// Send a GetData message
     pub fn send_getdata(&mut self, block_hashes: &Vec<Sha256dHash>) -> Result<(), btc_error> {
-        assert!(block_hashes.len() > 0);
+        assert!(!block_hashes.is_empty());
         let getdata_invs = block_hashes
             .iter()
             .map(|h| btc_message_blockdata::Inventory {

stackslib/src/burnchains/bitcoin/spv.rs

@@ -529,7 +529,7 @@ impl SpvClient {
         headers: &Vec<LoneBlockHeader>,
         check_txcount: bool,
     ) -> Result<(), btc_error> {
-        if headers.len() == 0 {
+        if headers.is_empty() {
             return Ok(());
         }
 
@@ -945,7 +945,7 @@ impl SpvClient {
     ) -> Result<(), btc_error> {
         assert!(self.readwrite, "SPV header DB is open read-only");
 
-        if block_headers.len() == 0 {
+        if block_headers.is_empty() {
             // no-op
             return Ok(());
         }
@@ -996,7 +996,7 @@ impl SpvClient {
         block_headers: Vec<LoneBlockHeader>,
     ) -> Result<(), btc_error> {
         assert!(self.readwrite, "SPV header DB is open read-only");
-        if block_headers.len() == 0 {
+        if block_headers.is_empty() {
             // no-op
             return Ok(());
         }
@@ -1137,7 +1137,7 @@ impl SpvClient {
         ]);
         let max_target_bits = BlockHeader::compact_target_from_u256(&max_target);
 
-        let parent_header = if headers_in_range.len() > 0 {
+        let parent_header = if !headers_in_range.is_empty() {
             headers_in_range[0]
         } else {
             match self.read_block_header(current_header_height - 1)? {

stackslib/src/burnchains/burnchain.rs

@@ -130,7 +130,7 @@ impl BurnchainStateTransition {
 
         block_total_burns.sort();
 
-        if block_total_burns.len() == 0 {
+        if block_total_burns.is_empty() {
             return Some(0);
         } else if block_total_burns.len() == 1 {
             return Some(block_total_burns[0]);

stackslib/src/burnchains/db.rs

@@ -452,7 +452,7 @@ impl<'a> BurnchainDBTransaction<'a> {
                 })
                 .collect()
         };
-        if commits.len() == 0 {
+        if commits.is_empty() {
             test_debug!("No block-commits for block {}", hdr.block_height);
             return Ok(());
         }

stackslib/src/burnchains/tests/burnchain.rs

@@ -574,7 +574,7 @@ fn test_process_block_ops() {
             acc
         });
 
-        let next_sortition = block_ops_124.len() > 0 && burn_total > 0;
+        let next_sortition = !block_ops_124.is_empty() && burn_total > 0;
 
         let mut block_124_snapshot = BlockSnapshot {
             accumulated_coinbase_ustx: 400_000_000,