Address some new clippy warnings

Author: weiznich

src/pg/mod.rs

@@ -123,7 +123,7 @@ impl AsyncConnection for AsyncPgConnection {
             .map_err(ErrorHelper)?;
         tokio::spawn(async move {
             if let Err(e) = connection.await {
-                eprintln!("connection error: {}", e);
+                eprintln!("connection error: {e}");
             }
         });
         Self::try_from(client).await

src/pooled_connection/mod.rs

@@ -39,14 +39,17 @@ impl fmt::Display for PoolError {
 
 impl std::error::Error for PoolError {}
 
+type SetupCallback<C> =
+    Box<dyn Fn(&str) -> future::BoxFuture<diesel::ConnectionResult<C>> + Send + Sync>;
+
 /// An connection manager for use with diesel-async.
 ///
 /// See the concrete pool implementations for examples:
 /// * [deadpool](self::deadpool)
 /// * [bb8](self::bb8)
 /// * [mobc](self::mobc)
 pub struct AsyncDieselConnectionManager<C> {
-    setup: Box<dyn Fn(&str) -> future::BoxFuture<diesel::ConnectionResult<C>> + Send + Sync>,
+    setup: SetupCallback<C>,
     connection_url: String,
 }
 

src/transaction_manager.rs

@@ -292,7 +292,7 @@ where
         let start_transaction_sql = match transaction_state.transaction_depth() {
             None => Cow::from("BEGIN"),
             Some(transaction_depth) => {
-                Cow::from(format!("SAVEPOINT diesel_savepoint_{}", transaction_depth))
+                Cow::from(format!("SAVEPOINT diesel_savepoint_{transaction_depth}"))
             }
         };
         conn.batch_execute(&start_transaction_sql).await?;