Merge pull request #1279 from matthiasbeyer/remove-let-unit

Clippy: Remove let unit

41 files changed, 121 insertions, 132 deletions

diff --git a/crates/common/certificate/src/lib.rs b/crates/common/certificate/src/lib.rs
index 0c81a73d..ecfbd88a 100644
--- a/crates/common/certificate/src/lib.rs
+++ b/crates/common/certificate/src/lib.rs
@@ -110,7 +110,7 @@ impl KeyCertPair {
         id: &str,
         not_before: OffsetDateTime,
     ) -> Result<KeyCertPair, CertificateError> {
-        let () = KeyCertPair::check_identifier(id, config.max_cn_size)?;
+        KeyCertPair::check_identifier(id, config.max_cn_size)?;
         let mut distinguished_name = rcgen::DistinguishedName::new();
         distinguished_name.push(rcgen::DnType::CommonName, id);
         distinguished_name.push(rcgen::DnType::OrganizationName, &config.organization_name);
diff --git a/crates/common/download/examples/simple_download.rs b/crates/common/download/examples/simple_download.rs
index e583b0eb..763a91c0 100644
--- a/crates/common/download/examples/simple_download.rs
+++ b/crates/common/download/examples/simple_download.rs
@@ -14,10 +14,10 @@ async fn main() -> Result<()> {
     let downloader = Downloader::new("test_download", &None, "/tmp");
 
     // Call `download` method to get data from url.
-    let () = downloader.download(&url_data).await?;
+    downloader.download(&url_data).await?;
 
     // Call cleanup method to remove downloaded file if no longer necessary.
-    let () = downloader.cleanup().await?;
+    downloader.cleanup().await?;
 
     Ok(())
 }
diff --git a/crates/common/download/src/download.rs b/crates/common/download/src/download.rs
index cc96f689..692cb1a7 100644
--- a/crates/common/download/src/download.rs
+++ b/crates/common/download/src/download.rs
@@ -219,7 +219,7 @@ mod tests {
         let url = DownloadInfo::new(&target_url);
 
         let downloader = Downloader::new(&name, &version, target_dir_path.path());
-        let () = downloader.download(&url).await?;
+        downloader.download(&url).await?;
 
         let log_content = std::fs::read(downloader.filename())?;
 
diff --git a/crates/common/flockfile/src/unix.rs b/crates/common/flockfile/src/unix.rs
index 4ef847d2..5980397f 100644
--- a/crates/common/flockfile/src/unix.rs
+++ b/crates/common/flockfile/src/unix.rs
@@ -56,7 +56,7 @@ impl Flockfile {
             }
         };
 
-        let () = match flock(file.as_raw_fd(), FlockArg::LockExclusiveNonblock) {
+        match flock(file.as_raw_fd(), FlockArg::LockExclusiveNonblock) {
             Ok(()) => (),
             Err(err) => {
                 return Err(FlockfileError::FromNix { path, source: err });
diff --git a/crates/common/json_writer/src/lib.rs b/crates/common/json_writer/src/lib.rs
index df92765b..c5a3c23f 100644
--- a/crates/common/json_writer/src/lib.rs
+++ b/crates/common/json_writer/src/lib.rs
@@ -41,7 +41,7 @@ impl JsonWriter {
 
     pub fn write_key(&mut self, key: &str) -> Result<(), JsonWriterError> {
         self.maybe_separate();
-        let () = serde_json::to_writer(&mut self.buffer, key)?;
+        serde_json::to_writer(&mut self.buffer, key)?;
         self.buffer.push(b':');
         self.needs_separator = false;
         Ok(())
@@ -49,7 +49,7 @@ impl JsonWriter {
 
     pub fn write_str(&mut self, s: &str) -> Result<(), JsonWriterError> {
         self.maybe_separate();
-        let () = serde_json::to_writer(&mut self.buffer, s)?;
+        serde_json::to_writer(&mut self.buffer, s)?;
         self.needs_separator = true;
         Ok(())
     }
@@ -58,7 +58,7 @@ impl JsonWriter {
         self.maybe_separate();
         match value.classify() {
             FpCategory::Normal | FpCategory::Zero | FpCategory::Subnormal => {
-                let () = serde_json::to_writer(&mut self.buffer, &value)?;
+                serde_json::to_writer(&mut self.buffer, &value)?;
                 self.needs_separator = true;
                 Ok(())
             }
diff --git a/crates/common/mqtt_channel/src/tests.rs b/crates/common/mqtt_channel/src/tests.rs
index fb30eac7..7a8201e5 100644
--- a/crates/common/mqtt_channel/src/tests.rs
+++ b/crates/common/mqtt_channel/src/tests.rs
@@ -99,7 +99,7 @@ mod tests {
         ]
         .into_iter()
         {
-            let () = broker.publish(topic, payload).await?;
+            broker.publish(topic, payload).await?;
             assert_eq!(
                 MaybeMessage::Next(message(topic, payload)),
                 next_message(&mut messages).await
@@ -113,7 +113,7 @@ mod tests {
         ]
         .into_iter()
         {
-            let () = broker.publish(topic, payload).await?;
+            broker.publish(topic, payload).await?;
             assert_eq!(MaybeMessage::Timeout, next_message(&mut messages).await);
         }
 
diff --git a/crates/common/tedge_config/src/tedge_config_repository.rs b/crates/common/tedge_config/src/tedge_config_repository.rs
index 5c818c7b..894116d8 100644
--- a/crates/common/tedge_config/src/tedge_config_repository.rs
+++ b/crates/common/tedge_config/src/tedge_config_repository.rs
@@ -32,10 +32,10 @@ impl ConfigRepository<TEdgeConfig> for TEdgeConfigRepository {
 
         // Create `$HOME/.tedge` or `/etc/tedge` directory in case it does not exist yet
         if !self.config_location.tedge_config_root_path.exists() {
-            let () = fs::create_dir(self.config_location.tedge_config_root_path())?;
+            fs::create_dir(self.config_location.tedge_config_root_path())?;
         }
 
-        let () = atomically_write_file_sync(
+        atomically_write_file_sync(
             self.config_location.temporary_tedge_config_file_path(),
             self.config_location.tedge_config_file_path(),
             toml.as_bytes(),
diff --git a/crates/common/tedge_utils/src/file.rs b/crates/common/tedge_utils/src/file.rs
index 4da9f1bf..f3659d56 100644
--- a/crates/common/tedge_utils/src/file.rs
+++ b/crates/common/tedge_utils/src/file.rs
@@ -74,19 +74,19 @@ impl PermissionEntry {
     pub fn apply(&self, path: &Path) -> Result<(), FileError> {
         match (&self.user, &self.group) {
             (Some(user), Some(group)) => {
-                let () = change_user_and_group(path, user, group)?;
+                change_user_and_group(path, user, group)?;
             }
             (Some(user), None) => {
-                let () = change_user(path, user)?;
+                change_user(path, user)?;
             }
             (None, Some(group)) => {
-                let () = change_group(path, group)?;
+                change_group(path, group)?;
             }
             (None, None) => {}
         }
 
         if let Some(mode) = &self.mode {
-            let () = change_mode(path, *mode)?;
+            change_mode(path, *mode)?;
         }
 
         Ok(())
@@ -95,7 +95,7 @@ impl PermissionEntry {
     fn create_directory(&self, dir: &Path) -> Result<(), FileError> {
         match fs::create_dir(dir) {
             Ok(_) => {
-                let () = self.apply(dir)?;
+                self.apply(dir)?;
                 Ok(())
             }
             Err(e) if e.kind() == io::ErrorKind::AlreadyExists => Ok(()),
@@ -119,7 +119,7 @@ impl PermissionEntry {
             .open(file)
         {
             Ok(mut f) => {
-                let () = self.apply(file)?;
+                self.apply(file)?;
                 if let Some(default_content) = default_content {
                     f.write(default_content.as_bytes()).map_err(|e| {
                         FileError::WriteContentFailed {
@@ -342,7 +342,7 @@ mod tests {
         assert!(format!("{:o}", perm.mode()).contains("644"));
 
         let permission_set = PermissionEntry::new(None, None, Some(0o444));
-        let () = permission_set.apply(Path::new(file_path.as_str())).unwrap();
+        permission_set.apply(Path::new(file_path.as_str())).unwrap();
 
         let meta = fs::metadata(file_path.as_str()).unwrap();
         let perm = meta.permissions();
diff --git a/crates/common/tedge_utils/src/fs.rs b/crates/common/tedge_utils/src/fs.rs
index fff39647..6f679891 100644
--- a/crates/common/tedge_utils/src/fs.rs
+++ b/crates/common/tedge_utils/src/fs.rs
@@ -41,14 +41,14 @@ pub async fn atomically_write_file_async(
         .await?;
 
     if let Err(err) = file.write_all(content).await {
-        let () = tokio_fs::remove_file(tempfile).await?;
+        tokio_fs::remove_file(tempfile).await?;
         return Err(err);
     }
 
     file.flush().await?;
 
     if let Err(err) = tokio_fs::rename(tempfile.as_ref(), dest).await {
-        let () = tokio_fs::remove_file(tempfile).await?;
+        tokio_fs::remove_file(tempfile).await?;
         return Err(err);
     }
 
@@ -69,7 +69,7 @@ mod tests {
 
         let content = "test_data";
 
-        let () = atomically_write_file_async(&temp_path, &destination_path, content.as_bytes())
+        atomically_write_file_async(&temp_path, &destination_path, content.as_bytes())
             .await
             .unwrap();
 
diff --git a/crates/common/tedge_utils/src/fs_notify.rs b/crates/common/tedge_utils/src/fs_notify.rs
index 414fca57..6745c180 100644
--- a/crates/common/tedge_utils/src/fs_notify.rs
+++ b/crates/common/tedge_utils/src/fs_notify.rs
@@ -536,8 +536,8 @@ mod tests {
             ttd_clone.file("file_b").with_raw_content("content");
         });
 
-        let () = fs_notify_handler.await.unwrap();
-        let () = file_handler.await.unwrap();
+        fs_notify_handler.await.unwrap();
+        file_handler.await.unwrap();
     }
 
     #[tokio::test]
@@ -568,7 +568,7 @@ mod tests {
             ttd_clone.file("file_c").delete(); // should match CREATE, DELETE
         });
 
-        let () = fs_notify_handler.await.unwrap();
-        let () = file_handler.await.unwrap();
+        fs_notify_handler.await.unwrap();
+        file_handler.await.unwrap();
     }
 }
diff --git a/crates/core/c8y_api/src/http_proxy.rs b/crates/core/c8y_api/src/http_proxy.rs
index 3d1288d6..83d9b6bf 100644
--- a/crates/core/c8y_api/src/http_proxy.rs
+++ b/crates/core/c8y_api/src/http_proxy.rs
@@ -157,8 +157,7 @@ impl C8yMqttJwtTokenRetriever {
 #[async_trait]
 impl C8yJwtTokenRetriever for C8yMqttJwtTokenRetriever {
     async fn get_jwt_token(&mut self) -> Result<SmartRestJwtResponse, SMCumulocityMapperError> {
-        let () = self
-            .mqtt_con
+        self.mqtt_con
             .published
             .publish(mqtt_channel::Message::new(
                 &Topic::new_unchecked("c8y/s/uat"),
@@ -237,7 +236,7 @@ impl JwtAuthHttpProxy {
         let mut mqtt_con = Connection::new(&mqtt_config).await?;
 
         // Ignore errors on this connection
-        let () = mqtt_con.errors.close();
+        mqtt_con.errors.close();
 
         let jwt_token_retriver = Box::new(C8yMqttJwtTokenRetriever::new(mqtt_con));
 
diff --git a/crates/core/c8y_smartrest/src/smartrest_deserializer.rs b/crates/core/c8y_smartrest/src/smartrest_deserializer.rs
index 54e96855..63b031fc 100644
--- a/crates/core/c8y_smartrest/src/smartrest_deserializer.rs
+++ b/crates/core/c8y_smartrest/src/smartrest_deserializer.rs
@@ -57,7 +57,7 @@ impl Default for SmartRestUpdateSoftware {
 impl SmartRestUpdateSoftware {
     pub fn from_smartrest(&self, smartrest: &str) -> Result<Self, SmartRestDeserializerError> {
         let mut message_id = smartrest.to_string();
-        let () = message_id.truncate(3);
+        message_id.truncate(3);
 
         let mut rdr = ReaderBuilder::new()
             .has_headers(false)
@@ -461,7 +461,7 @@ mod tests {
                 url: Some("url1".into()),
                 file_path: None,
             }));
-        let () = expected_thin_edge_json.add_update(SoftwareModuleUpdate::remove(SoftwareModule {
+        expected_thin_edge_json.add_update(SoftwareModuleUpdate::remove(SoftwareModule {
             module_type: Some("".to_string()),
             name: "software2".to_string(),
             version: None,
diff --git a/crates/core/c8y_translator/src/json.rs b/crates/core/c8y_translator/src/json.rs
index 0ecacd4f..41d8ae35 100644
--- a/crates/core/c8y_translator/src/json.rs
+++ b/crates/core/c8y_translator/src/json.rs
@@ -50,7 +50,7 @@ fn from_thin_edge_json_with_timestamp(
     maybe_child_id: Option<&str>,
 ) -> Result<String, CumulocityJsonError> {
     let mut serializer = serializer::C8yJsonSerializer::new(timestamp, maybe_child_id);
-    let () = parse_str(input, &mut serializer)?;
+    parse_str(input, &mut serializer)?;
     Ok(serializer.into_string()?)
 }
 
diff --git a/crates/core/plugin_sm/src/operation_logs.rs b/crates/core/plugin_sm/src/operation_logs.rs
index 7bf08eab..7912eaa7 100644
--- a/crates/core/plugin_sm/src/operation_logs.rs
+++ b/crates/core/plugin_sm/src/operation_logs.rs
@@ -108,10 +108,10 @@ impl OperationLogs {
         for (key, value) in log_tracker.iter_mut() {
             if key.starts_with("software-list") {
                 // only allow one update list file in logs
-                let () = remove_old_logs(value, &self.log_dir, 1)?;
+                remove_old_logs(value, &self.log_dir, 1)?;
             } else {
                 // allow most recent five
-                let () = remove_old_logs(value, &self.log_dir, 5)?;
+                remove_old_logs(value, &self.log_dir, 5)?;
             }
         }
 
diff --git a/crates/core/plugin_sm/tests/plugin.rs b/crates/core/plugin_sm/tests/plugin.rs
index 724813fb..366bfbcf 100644
--- a/crates/core/plugin_sm/tests/plugin.rs
+++ b/crates/core/plugin_sm/tests/plugin.rs
@@ -410,7 +410,7 @@ mod tests {
     fn get_dummy_plugin_tmp_path() -> PathBuf {
         let path = PathBuf::from_str("/tmp/.tedge_dummy_plugin").unwrap();
         if !&path.exists() {
-            let () = fs::create_dir(&path).unwrap();
+            fs::create_dir(&path).unwrap();
         }
         path
     }
diff --git a/crates/core/tedge/src/cli/certificate/create.rs b/crates/core/tedge/src/cli/certificate/create.rs
index 2d1589c9..83eeb45f 100644
--- a/crates/core/tedge/src/cli/certificate/create.rs
+++ b/crates/core/tedge/src/cli/certificate/create.rs
@@ -28,7 +28,7 @@ impl Command for CreateCertCmd {
 
     fn execute(&self) -> anyhow::Result<()> {
         let config = NewCertificateConfig::default();
-        let () = self.create_test_certificate(&config)?;
+        self.create_test_certificate(&config)?;
         Ok(())
     }
 }
diff --git a/crates/core/tedge/src/cli/certificate/remove.rs b/crates/core/tedge/src/cli/certificate/remove.rs
index 8f978972..c1007b44 100644
--- a/crates/core/tedge/src/cli/certificate/remove.rs
+++ b/crates/core/tedge/src/cli/certificate/remove.rs
@@ -18,7 +18,7 @@ impl Command for RemoveCertCmd {
     }
 
     fn execute(&self) -> anyhow::Result<()> {
-        let () = self.remove_certificate()?;
+        self.remove_certificate()?;
         Ok(())
     }
 }
diff --git a/crates/core/tedge/src/cli/certificate/show.rs b/crates/core/tedge/src/cli/certificate/show.rs
index 8890f308..24bc493d 100644
--- a/crates/core/tedge/src/cli/certificate/show.rs
+++ b/crates/core/tedge/src/cli/certificate/show.rs
@@ -16,7 +16,7 @@ impl Command for ShowCertCmd {
     }
 
     fn execute(&self) -> anyhow::Result<()> {
-        let () = self.show_certificate()?;
+        self.show_certificate()?;
         Ok(())
     }
 }
diff --git a/crates/core/tedge/src/cli/config/commands/set.rs b/crates/core/tedge/src/cli/config/commands/set.rs
index 715f2664..ce2493a6 100644
--- a/crates/core/tedge/src/cli/config/commands/set.rs
+++ b/crates/core/tedge/src/cli/config/commands/set.rs
@@ -18,7 +18,7 @@ impl Command for SetConfigCommand {
 
     fn execute(&self) -> anyhow::Result<()> {
         let mut config = self.config_repository.load()?;
-        let () = (self.config_key.set)(&mut config, self.value.to_string())?;
+        (self.config_key.set)(&mut config, self.value.to_string())?;
         self.config_repository.store(&config)?;
         Ok(())
     }
diff --git a/crates/core/tedge/src/cli/config/commands/unset.rs b/crates/core/tedge/src/cli/config/commands/unset.rs
index 222d8a3e..a975a58d 100644
--- a/crates/core/tedge/src/cli/config/commands/unset.rs
+++ b/crates/core/tedge/src/cli/config/commands/unset.rs
@@ -17,7 +17,7 @@ impl Command for UnsetConfigCommand {
 
     fn execute(&self) -> anyhow::Result<()> {
         let mut config = self.config_repository.load()?;
-        let () = (self.config_key.unset)(&mut config)?;
+        (self.config_key.unset)(&mut config)?;
         self.config_repository.store(&config)?;
         Ok(())
     }
diff --git a/crates/core/tedge/src/cli/connect/c8y_direct_connection.rs b/crates/core/tedge/src/cli/connect/c8y_direct_connection.rs
index 89400667..1683b4d8 100644
--- a/crates/core/tedge/src/cli/connect/c8y_direct_connection.rs
+++ b/crates/core/tedge/src/cli/connect/c8y_direct_connection.rs
@@ -29,7 +29,7 @@ pub fn create_device_with_direct_connection(
 
     let mut client_config = ClientConfig::new();
 
-    let () = load_root_certs(
+    load_root_certs(
         &mut client_config.root_store,
         bridge_config.bridge_root_cert_path.clone(),
     )?;
diff --git a/crates/core/tedge/src/cli/connect/command.rs b/crates/core/tedge/src/cli/connect/command.rs
index 8714bdd7..c525eb1d 100644
--- a/crates/core/tedge/src/cli/connect/command.rs
+++ b/crates/core/tedge/src/cli/connect/command.rs
@@ -242,7 +242,7 @@ where
     TEdgeConfig: ConfigSettingAccessor<T>,
 {
     let value = config.query(setting)?;
-    let () = config.update(setting, value)?;
+    config.update(setting, value)?;
     Ok(())
 }
 
@@ -402,17 +402,14 @@ fn new_bridge(
     }
 
     println!("Checking if configuration for requested bridge already exists.\n");
-    let () = bridge_config_exists(config_location, bridge_config)?;
+    bridge_config_exists(config_location, bridge_config)?;
 
     println!("Validating the bridge certificates.\n");
-    let () = bridge_config.validate()?;
+    bridge_config.validate()?;
 
     if bridge_config.cloud_name.eq("c8y") {
         println!("Creating the device in Cumulocity cloud.\n");
-        let () = c8y_direct_connection::create_device_with_direct_connection(
-            bridge_config,
-            device_type,
-        )?;
+        c8y_direct_connection::create_device_with_direct_connection(bridge_config, device_type)?;
     }
 
     println!("Saving configuration for requested bridge.\n");
@@ -522,12 +519,12 @@ fn write_bridge_config_to_file(
         get_common_mosquitto_config_file_path(config_location, common_mosquitto_config);
     let mut common_draft = DraftFile::new(&common_config_path)?;
     common_mosquitto_config.serialize(&mut common_draft)?;
-    let () = common_draft.persist()?;
+    common_draft.persist()?;
 
     let config_path = get_bridge_config_file_path(config_location, bridge_config);
     let mut config_draft = DraftFile::new(config_path)?;
     bridge_config.serialize(&mut config_draft)?;
-    let () = config_draft.persist()?;
+    config_draft.persist()?;
 
     Ok(())
 }
diff --git a/crates/core/tedge/src/system_services/manager.rs b/crates/core/tedge/src/system_services/manager.rs
index 83b4cd56..08caf6d9 100644
--- a/crates/core/tedge/src/system_services/manager.rs
+++ b/crates/core/tedge/src/system_services/manager.rs
@@ -33,7 +33,7 @@ pub trait SystemServiceManager: Debug {
         service: SystemService,
     ) -> Result<bool, SystemServiceError> {
         if self.is_service_running(service)? {
-            let () = self.restart_service(service)?;
+            self.restart_service(service)?;
             Ok(true)
         } else {
             Ok(false)
diff --git a/crates/core/tedge_agent/src/agent.rs b/crates/core/tedge_agent/src/agent.rs
index 69acdd40..bf8f2821 100644
--- a/crates/core/tedge_agent/src/agent.rs
+++ b/