Simplify empty check, relace length validation to is_empty()

leaf/src/app/router.rs

@@ -424,15 +424,15 @@ impl Router {
         for rr in routing_rules.iter_mut() {
             let mut cond_and = ConditionAnd::new();
 
-            if rr.domains.len() > 0 {
+            if !rr.domains.is_empty() {
                 cond_and.add(Box::new(DomainMatcher::new(&mut rr.domains)));
             }
 
-            if rr.ip_cidrs.len() > 0 {
+            if !rr.ip_cidrs.is_empty() {
                 cond_and.add(Box::new(IpCidrMatcher::new(&mut rr.ip_cidrs)));
             }
 
-            if rr.mmdbs.len() > 0 {
+            if !rr.mmdbs.is_empty() {
                 for mmdb in rr.mmdbs.iter() {
                     let reader = match mmdb_readers.get(&mmdb.file) {
                         Some(r) => r.clone(),
@@ -455,15 +455,15 @@ impl Router {
                 }
             }
 
-            if rr.port_ranges.len() > 0 {
+            if !rr.port_ranges.is_empty() {
                 cond_and.add(Box::new(PortMatcher::new(&rr.port_ranges)));
             }
 
-            if rr.networks.len() > 0 {
+            if !rr.networks.is_empty() {
                 cond_and.add(Box::new(NetworkMatcher::new(&mut rr.networks)));
             }
 
-            if rr.inbound_tags.len() > 0 {
+            if !rr.inbound_tags.is_empty() {
                 cond_and.add(Box::new(InboundTagMatcher::new(&mut rr.inbound_tags)));
             }
 

leaf/src/common/sniff.rs

@@ -65,7 +65,7 @@ where
         let bytes_str = String::from_utf8_lossy(buf);
         let parts: Vec<&str> = bytes_str.split("\r\n").collect();
 
-        if parts.len() == 0 {
+        if parts.is_empty() {
             return SniffResult::NotMatch;
         }
 
@@ -84,7 +84,7 @@ where
         }
 
         for (idx, &el) in parts.iter().enumerate() {
-            if idx == 0 || el == "" {
+            if idx == 0 || el.is_empty() {
                 continue;
             }
             let inner_parts: Vec<&str> = el.split(":").collect();

leaf/src/config/conf/config.rs

@@ -797,7 +797,7 @@ pub fn to_internal(conf: &mut Config) -> Result<internal::Config> {
                 for item in ext_always_real_ip {
                     fake_dns_exclude.push(item.clone())
                 }
-                if fake_dns_exclude.len() > 0 {
+                if !fake_dns_exclude.is_empty() {
                     settings.fake_dns_exclude = fake_dns_exclude;
                 }
             }
@@ -807,7 +807,7 @@ pub fn to_internal(conf: &mut Config) -> Result<internal::Config> {
                 for item in ext_always_fake_ip {
                     fake_dns_include.push(item.clone())
                 }
-                if fake_dns_include.len() > 0 {
+                if !fake_dns_include.is_empty() {
                     settings.fake_dns_include = fake_dns_include;
                 }
             }

leaf/src/config/json/config.rs

@@ -347,7 +347,7 @@ pub fn to_internal(json: &mut Config) -> Result<internal::Config> {
                             fake_dns_exclude.push(ext_exclude);
                         }
                     }
-                    if fake_dns_exclude.len() > 0 {
+                    if !fake_dns_exclude.is_empty() {
                         settings.fake_dns_exclude = fake_dns_exclude;
                     }
 
@@ -357,7 +357,7 @@ pub fn to_internal(json: &mut Config) -> Result<internal::Config> {
                             fake_dns_include.push(ext_include);
                         }
                     }
-                    if fake_dns_include.len() > 0 {
+                    if !fake_dns_include.is_empty() {
                         settings.fake_dns_include = fake_dns_include;
                     }
 
@@ -707,7 +707,7 @@ pub fn to_internal(json: &mut Config) -> Result<internal::Config> {
                                 alpns.push(ext_alpn);
                             }
                         }
-                        if alpns.len() > 0 {
+                        if !alpns.is_empty() {
                             settings.alpn = alpns;
                         }
                         if let Some(ext_certificate) = ext_settings.certificate {

leaf/src/proxy/tls/outbound/stream.rs

@@ -137,7 +137,7 @@ impl Handler {
             }
             let mut builder =
                 SslConnector::builder(SslMethod::tls()).expect("create ssl connector failed");
-            if alpns.len() > 0 {
+            if !alpns.is_empty() {
                 let wire = alpns
                     .into_iter()
                     .map(|a| [&[a.len() as u8], a.as_bytes()].concat())