diff --git a/dt-core/src/item.rs b/dt-core/src/item.rs
index 779d447..e5387ba 100644
--- a/dt-core/src/item.rs
+++ b/dt-core/src/item.rs
@@ -152,7 +152,7 @@ impl Operate for PathBuf {
     /// Reference: <https://stackoverflow.com/a/54817755/13482274>
     fn absolute(self) -> Result<Self> {
         let absolute_path = if self.is_absolute() {
-            self.to_owned()
+            self
         } else {
             std::env::current_dir()?.join(self)
         }
@@ -165,7 +165,7 @@ impl Operate for PathBuf {
     /// host-specific, returns `self` directly.
     fn host_specific(self, hostname_sep: &str) -> Self {
         if self.ends_with(utils::host_specific_suffix(hostname_sep)) {
-            self.into()
+            self
         } else {
             let hs_filename = self
                 .file_name()
@@ -417,7 +417,7 @@ impl Operate for PathBuf {
         renaming_rules: Vec<RenamingRule>,
     ) -> Result<Self> {
         // Get non-host-specific counterpart of `self`
-        let nhself = self.to_owned().non_host_specific(hostname_sep);
+        let nhself = self.non_host_specific(hostname_sep);
 
         // Get non-host-specific counterpart of `base`
         let base = base.to_owned().non_host_specific(hostname_sep);
diff --git a/dt-core/src/lib.rs b/dt-core/src/lib.rs
index 3f14227..0d38c03 100644
--- a/dt-core/src/lib.rs
+++ b/dt-core/src/lib.rs
@@ -254,7 +254,6 @@ sources = ["{}"]
                 )?,
             );
 
-            let test_username = "watson";
             let config = expand(DTConfig::from_str(&format!(
                 r#"
 [context.user]
diff --git a/dt-core/src/registry.rs b/dt-core/src/registry.rs
index 2de7b3a..f6221af 100644
--- a/dt-core/src/registry.rs
+++ b/dt-core/src/registry.rs
@@ -346,7 +346,7 @@ Block helper `#{0}`:
             .unwrap()
             .to_string_lossy()
             .to_string();
-        if allowed_usernames.len() > 0 {
+        if !allowed_usernames.is_empty() {
             if allowed_usernames.contains(&current_username) {
                 log::debug!(
                     "Current username '{}' matches allowed usernames '{:?}'",
@@ -472,7 +472,7 @@ Block helper `#{0}`:
             .unwrap()
             .to_string_lossy()
             .to_string();
-        if disallowed_usernames.len() > 0 {
+        if !disallowed_usernames.is_empty() {
             if disallowed_usernames.contains(&current_username) {
                 log::debug!(
                     "Current username '{}' matches disallowed usernames '{:?}'",
@@ -592,7 +592,7 @@ Block helper `#{0}`:
         };
 
         let current_uid = get_current_uid();
-        if allowed_uids.len() > 0 {
+        if !allowed_uids.is_empty() {
             if allowed_uids.contains(&current_uid) {
                 log::debug!(
                     "Current uid '{}' matches allowed uids '{:?}'",
@@ -713,7 +713,7 @@ Block helper `#{0}`:
         };
 
         let current_uid = get_current_uid();
-        if disallowed_uids.len() > 0 {
+        if !disallowed_uids.is_empty() {
             if disallowed_uids.contains(&current_uid) {
                 log::debug!(
                     "Current uid '{}' matches disallowed uids '{:?}'",
@@ -835,7 +835,7 @@ Block helper `#{0}`:
         let current_hostname = gethostname();
         let current_hostname: String =
             current_hostname.to_string_lossy().to_string();
-        if allowed_hostnames.len() > 0 {
+        if !allowed_hostnames.is_empty() {
             if allowed_hostnames.contains(&current_hostname) {
                 log::debug!(
                     "Current hostname '{}' matches allowed hostnames '{:?}'",
@@ -958,7 +958,7 @@ Block helper `#{0}`:
         let current_hostname = gethostname();
         let current_hostname: String =
             current_hostname.to_string_lossy().to_string();
-        if disallowed_hostnames.len() > 0 {
+        if !disallowed_hostnames.is_empty() {
             if disallowed_hostnames.contains(&current_hostname) {
                 log::debug!(
                     "Current hostname '{}' matches disallowed hostnames '{:?}'",
diff --git a/dt-core/src/syncing.rs b/dt-core/src/syncing.rs
index 020dd8d..17e0fcb 100644
--- a/dt-core/src/syncing.rs
+++ b/dt-core/src/syncing.rs
@@ -343,6 +343,7 @@ pub fn sync(config: DTConfig, dry_run: bool) -> Result<()> {
                     }
                 }
             } else {
+                #[allow(clippy::collapsible_else_if)]
                 if let Err(e) = spath
                     .populate(Rc::clone(&group_ref), Rc::clone(&registry))
                 {