fix: clippy warnings

.github/workflows/sqlx.yml

@@ -34,6 +34,7 @@ jobs:
           rustup update
           rustup component add clippy
           rustup toolchain install beta
+          rustup component add --toolchain beta clippy
 
       - run: >
           cargo clippy

clippy.toml

@@ -1,5 +1,13 @@
-disallowed-methods = [
-    # It is *much* too easy to misread `x.min(y)` as "x should be *at least* y" when in fact it
-    # means the *exact* opposite, and same with `x.max(y)`; use `cmp::{min, max}` instead.
-    "core::cmp::Ord::min", "core::cmp::Ord::max"
-]
+[[disallowed-methods]]
+path = "core::cmp::Ord::min"
+reason = '''
+too easy to misread `x.min(y)` as "let the minimum value of `x` be `y`" when it actually means the exact opposite;
+use `std::cmp::min` instead.
+'''
+
+[[disallowed-methods]]
+path = "core::cmp::Ord::max"
+reason = '''
+too easy to misread `x.max(y)` as "let the maximum value of `x` be `y`" when it actually means the exact opposite;
+use `std::cmp::max` instead.
+'''

sqlx-cli/src/lib.rs

@@ -129,16 +129,15 @@ where
             .build(),
         || {
             connect(db_url).map_err(|e| -> backoff::Error<anyhow::Error> {
-                match e {
-                    sqlx::Error::Io(ref ioe) => match ioe.kind() {
+                if let sqlx::Error::Io(ref ioe) = e {
+                    match ioe.kind() {
                         io::ErrorKind::ConnectionRefused
                         | io::ErrorKind::ConnectionReset
                         | io::ErrorKind::ConnectionAborted => {
                             return backoff::Error::transient(e.into());
                         }
                         _ => (),
-                    },
-                    _ => (),
+                    }
                 }
 
                 backoff::Error::permanent(e.into())

sqlx-cli/src/metadata.rs

@@ -83,7 +83,7 @@ impl Metadata {
         self.packages.get(id)
     }
 
-    pub fn entries<'this>(&'this self) -> btree_map::Iter<'this, MetadataId, Package> {
+    pub fn entries(&self) -> btree_map::Iter<'_, MetadataId, Package> {
         self.packages.iter()
     }
 

sqlx-cli/src/migrate.rs

@@ -20,7 +20,7 @@ fn create_file(
     use std::path::PathBuf;
 
     let mut file_name = file_prefix.to_string();
-    file_name.push_str("_");
+    file_name.push('_');
     file_name.push_str(&description.replace(' ', "_"));
     file_name.push_str(migration_type.suffix());
 
@@ -120,20 +120,20 @@ pub async fn add(
     if migration_type.is_reversible() {
         create_file(
             migration_source,
-            &file_prefix,
+            file_prefix,
             description,
             MigrationType::ReversibleUp,
         )?;
         create_file(
             migration_source,
-            &file_prefix,
+            file_prefix,
             description,
             MigrationType::ReversibleDown,
         )?;
     } else {
         create_file(
             migration_source,
-            &file_prefix,
+            file_prefix,
             description,
             MigrationType::Simple,
         )?;
@@ -194,7 +194,7 @@ fn short_checksum(checksum: &[u8]) -> String {
 
 pub async fn info(migration_source: &str, connect_opts: &ConnectOpts) -> anyhow::Result<()> {
     let migrator = Migrator::new(Path::new(migration_source)).await?;
-    let mut conn = crate::connect(&connect_opts).await?;
+    let mut conn = crate::connect(connect_opts).await?;
 
     conn.ensure_migrations_table().await?;
 
@@ -300,7 +300,7 @@ pub async fn run(
     let latest_version = applied_migrations
         .iter()
         .max_by(|x, y| x.version.cmp(&y.version))
-        .and_then(|migration| Some(migration.version))
+        .map(|migration| migration.version)
         .unwrap_or(0);
     if let Some(target_version) = target_version {
         if target_version < latest_version {
@@ -326,10 +326,8 @@ pub async fn run(
                 }
             }
             None => {
-                let skip = match target_version {
-                    Some(target_version) if migration.version > target_version => true,
-                    _ => false,
-                };
+                let skip =
+                    target_version.is_some_and(|target_version| migration.version > target_version);
 
                 let elapsed = if dry_run || skip {
                     Duration::new(0, 0)
@@ -380,7 +378,7 @@ pub async fn revert(
         }
     }
 
-    let mut conn = crate::connect(&connect_opts).await?;
+    let mut conn = crate::connect(connect_opts).await?;
 
     conn.ensure_migrations_table().await?;
 
@@ -395,7 +393,7 @@ pub async fn revert(
     let latest_version = applied_migrations
         .iter()
         .max_by(|x, y| x.version.cmp(&y.version))
-        .and_then(|migration| Some(migration.version))
+        .map(|migration| migration.version)
         .unwrap_or(0);
     if let Some(target_version) = target_version {
         if target_version > latest_version {
@@ -417,10 +415,9 @@ pub async fn revert(
         }
 
         if applied_migrations.contains_key(&migration.version) {
-            let skip = match target_version {
-                Some(target_version) if migration.version <= target_version => true,
-                _ => false,
-            };
+            let skip =
+                target_version.is_some_and(|target_version| migration.version <= target_version);
+
             let elapsed = if dry_run || skip {
                 Duration::new(0, 0)
             } else {
@@ -447,7 +444,7 @@ pub async fn revert(
 
             // Only a single migration will be reverted at a time if no target
             // version is supplied, so we break.
-            if let None = target_version {
+            if target_version.is_none() {
                 break;
             }
         }

sqlx-core/src/any/connection/executor.rs

@@ -11,13 +11,13 @@ use std::future;
 impl<'c> Executor<'c> for &'c mut AnyConnection {
     type Database = Any;
 
-    fn fetch_many<'e, 'q: 'e, E: 'q>(
+    fn fetch_many<'e, 'q: 'e, E>(
         self,
         mut query: E,
     ) -> BoxStream<'e, Result<Either<AnyQueryResult, AnyRow>, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Any>,
+        E: 'q + Execute<'q, Any>,
     {
         let arguments = match query.take_arguments().map_err(Error::Encode) {
             Ok(arguments) => arguments,
@@ -26,13 +26,13 @@ impl<'c> Executor<'c> for &'c mut AnyConnection {
         self.backend.fetch_many(query.sql(), arguments)
     }
 
-    fn fetch_optional<'e, 'q: 'e, E: 'q>(
+    fn fetch_optional<'e, 'q: 'e, E>(
         self,
         mut query: E,
     ) -> BoxFuture<'e, Result<Option<AnyRow>, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>,
+        E: 'q + Execute<'q, Self::Database>,
     {
         let arguments = match query.take_arguments().map_err(Error::Encode) {
             Ok(arguments) => arguments,

sqlx-core/src/any/statement.rs

@@ -38,7 +38,7 @@ impl<'q> Statement<'q> for AnyStatement<'q> {
 
     fn parameters(&self) -> Option<Either<&[AnyTypeInfo], usize>> {
         match &self.parameters {
-            Some(Either::Left(types)) => Some(Either::Left(&types)),
+            Some(Either::Left(types)) => Some(Either::Left(types)),
             Some(Either::Right(count)) => Some(Either::Right(*count)),
             None => None,
         }
@@ -57,7 +57,7 @@ impl<'i> ColumnIndex<AnyStatement<'_>> for &'i str {
             .column_names
             .get(*self)
             .ok_or_else(|| Error::ColumnNotFound((*self).into()))
-            .map(|v| *v)
+            .copied()
     }
 }
 

sqlx-core/src/arguments.rs

@@ -7,6 +7,8 @@ use crate::types::Type;
 use std::fmt::{self, Write};
 
 /// A tuple of arguments to be sent to the database.
+// This lint is designed for general collections, but `Arguments` is not meant to be as such.
+#[allow(clippy::len_without_is_empty)]
 pub trait Arguments<'q>: Send + Sized + Default {
     type Database: Database;
 

sqlx-core/src/common/statement_cache.rs

@@ -43,6 +43,10 @@ impl<T> StatementCache<T> {
         self.inner.len()
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.inner.is_empty()
+    }
+
     /// Removes the least recently used item from the cache.
     pub fn remove_lru(&mut self) -> Option<T> {
         self.inner.remove_lru().map(|(_, v)| v)

sqlx-core/src/connection.rs

@@ -143,7 +143,7 @@ pub trait Connection: Send {
     {
         let options = url.parse();
 
-        Box::pin(async move { Ok(Self::connect_with(&options?).await?) })
+        Box::pin(async move { Self::connect_with(&options?).await })
     }
 
     /// Establish a new database connection with the provided options.

sqlx-core/src/executor.rs

@@ -34,25 +34,25 @@ pub trait Executor<'c>: Send + Debug + Sized {
     type Database: Database;
 
     /// Execute the query and return the total number of rows affected.
-    fn execute<'e, 'q: 'e, E: 'q>(
+    fn execute<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxFuture<'e, Result<<Self::Database as Database>::QueryResult, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>,
+        E: 'q + Execute<'q, Self::Database>,
     {
         self.execute_many(query).try_collect().boxed()
     }
 
     /// Execute multiple queries and return the rows affected from each query, in a stream.
-    fn execute_many<'e, 'q: 'e, E: 'q>(
+    fn execute_many<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxStream<'e, Result<<Self::Database as Database>::QueryResult, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>,
+        E: 'q + Execute<'q, Self::Database>,
     {
         self.fetch_many(query)
             .try_filter_map(|step| async move {
@@ -65,13 +65,13 @@ pub trait Executor<'c>: Send + Debug + Sized {
     }
 
     /// Execute the query and return the generated results as a stream.
-    fn fetch<'e, 'q: 'e, E: 'q>(
+    fn fetch<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxStream<'e, Result<<Self::Database as Database>::Row, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>,
+        E: 'q + Execute<'q, Self::Database>,
     {
         self.fetch_many(query)
             .try_filter_map(|step| async move {
@@ -85,7 +85,7 @@ pub trait Executor<'c>: Send + Debug + Sized {
 
     /// Execute multiple queries and return the generated results as a stream
     /// from each query, in a stream.
-    fn fetch_many<'e, 'q: 'e, E: 'q>(
+    fn fetch_many<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxStream<
@@ -97,28 +97,28 @@ pub trait Executor<'c>: Send + Debug + Sized {
     >
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>;
+        E: 'q + Execute<'q, Self::Database>;
 
     /// Execute the query and return all the generated results, collected into a [`Vec`].
-    fn fetch_all<'e, 'q: 'e, E: 'q>(
+    fn fetch_all<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxFuture<'e, Result<Vec<<Self::Database as Database>::Row>, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>,
+        E: 'q + Execute<'q, Self::Database>,
     {
         self.fetch(query).try_collect().boxed()
     }
 
     /// Execute the query and returns exactly one row.
-    fn fetch_one<'e, 'q: 'e, E: 'q>(
+    fn fetch_one<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxFuture<'e, Result<<Self::Database as Database>::Row, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>,
+        E: 'q + Execute<'q, Self::Database>,
     {
         self.fetch_optional(query)
             .and_then(|row| match row {
@@ -129,13 +129,13 @@ pub trait Executor<'c>: Send + Debug + Sized {
     }
 
     /// Execute the query and returns at most one row.
-    fn fetch_optional<'e, 'q: 'e, E: 'q>(
+    fn fetch_optional<'e, 'q: 'e, E>(
         self,
         query: E,
     ) -> BoxFuture<'e, Result<Option<<Self::Database as Database>::Row>, Error>>
     where
         'c: 'e,
-        E: Execute<'q, Self::Database>;
+        E: 'q + Execute<'q, Self::Database>;
 
     /// Prepare the SQL query to inspect the type information of its parameters
     /// and results.

sqlx-core/src/ext/async_stream.rs

@@ -121,10 +121,10 @@ impl<'a, T> Stream for TryAsyncStream<'a, T> {
 #[macro_export]
 macro_rules! try_stream {
     ($($block:tt)*) => {
-        crate::ext::async_stream::TryAsyncStream::new(move |yielder| async move {
+        $crate::ext::async_stream::TryAsyncStream::new(move |yielder| async move {
             // Anti-footgun: effectively pins `yielder` to this future to prevent any accidental
             // move to another task, which could deadlock.
-            let ref yielder = yielder;
+            let yielder = &yielder;
 
             macro_rules! r#yield {
                 ($v:expr) => {{

sqlx-core/src/ext/ustr.rs

@@ -36,14 +36,14 @@ impl Hash for UStr {
     fn hash<H: Hasher>(&self, state: &mut H) {
         // Forward the hash to the string representation of this
         // A derive(Hash) encodes the enum discriminant
-        (&**self).hash(state);
+        (**self).hash(state);
     }
 }
 
 impl Borrow<str> for UStr {
     #[inline]
     fn borrow(&self) -> &str {
-        &**self
+        self
     }
 }
 
@@ -102,6 +102,6 @@ impl serde::Serialize for UStr {
     where
         S: serde::Serializer,
     {
-        serializer.serialize_str(&self)
+        serializer.serialize_str(self)
     }
 }