Reduce futures-util

Cargo.toml

@@ -13,12 +13,13 @@ description = "An async extension for Diesel the safe, extensible ORM and Query
 rust-version = "1.82.0"
 
 [dependencies]
+futures-core = "0.3.17"
 futures-channel = { version = "0.3.17", default-features = false, features = [
   "std",
   "sink",
 ], optional = true }
 futures-util = { version = "0.3.17", default-features = false, features = [
-  "std",
+  "alloc",
   "sink",
 ] }
 tokio-postgres = { version = "0.7.10", optional = true }

src/async_connection_wrapper.rs

@@ -9,9 +9,9 @@
 //!   as replacement for the existing connection
 //!   implementations provided by diesel
 
-use futures_util::Future;
-use futures_util::Stream;
+use futures_core::Stream;
 use futures_util::StreamExt;
+use std::future::Future;
 use std::pin::Pin;
 
 /// This is a helper trait that allows to customize the

src/lib.rs

@@ -78,9 +78,11 @@ use diesel::connection::{CacheSize, Instrumentation};
 use diesel::query_builder::{AsQuery, QueryFragment, QueryId};
 use diesel::row::Row;
 use diesel::{ConnectionResult, QueryResult};
-use futures_util::future::BoxFuture;
-use futures_util::{Future, FutureExt, Stream};
+use futures_core::future::BoxFuture;
+use futures_core::Stream;
+use futures_util::FutureExt;
 use std::fmt::Debug;
+use std::future::Future;
 
 pub use scoped_futures;
 use scoped_futures::{ScopedBoxFuture, ScopedFutureExt};
@@ -322,15 +324,15 @@ pub trait AsyncConnection: SimpleAsyncConnection + Sized + Send {
                 .map_err(|_| diesel::result::Error::RollbackTransaction)
                 .and_then(move |r| {
                     let _ = user_result_tx.send(r);
-                    futures_util::future::ready(Err(diesel::result::Error::RollbackTransaction))
+                    std::future::ready(Err(diesel::result::Error::RollbackTransaction))
                 })
                 .scope_boxed()
         })
         .then(move |_r| {
             let r = user_result_rx
                 .try_recv()
                 .expect("Transaction did not succeed");
-            futures_util::future::ready(r)
+            std::future::ready(r)
         })
     }
 

src/mysql/mod.rs

@@ -11,11 +11,13 @@ use diesel::query_builder::QueryBuilder;
 use diesel::query_builder::{bind_collector::RawBytesBindCollector, QueryFragment, QueryId};
 use diesel::result::{ConnectionError, ConnectionResult};
 use diesel::QueryResult;
-use futures_util::future::BoxFuture;
-use futures_util::stream::{self, BoxStream};
-use futures_util::{Future, FutureExt, StreamExt, TryStreamExt};
+use futures_core::future::BoxFuture;
+use futures_core::stream::BoxStream;
+use futures_util::stream;
+use futures_util::{FutureExt, StreamExt, TryStreamExt};
 use mysql_async::prelude::Queryable;
 use mysql_async::{Opts, OptsBuilder, Statement};
+use std::future::Future;
 
 mod error_helper;
 mod row;

src/pg/mod.rs

@@ -22,12 +22,14 @@ use diesel::query_builder::bind_collector::RawBytesBindCollector;
 use diesel::query_builder::{AsQuery, QueryBuilder, QueryFragment, QueryId};
 use diesel::result::{DatabaseErrorKind, Error};
 use diesel::{ConnectionError, ConnectionResult, QueryResult};
-use futures_util::future::BoxFuture;
+use futures_core::future::BoxFuture;
+use futures_core::stream::BoxStream;
 use futures_util::future::Either;
-use futures_util::stream::{BoxStream, TryStreamExt};
+use futures_util::stream::TryStreamExt;
 use futures_util::TryFutureExt;
-use futures_util::{Future, FutureExt, StreamExt};
+use futures_util::{FutureExt, StreamExt};
 use std::collections::{HashMap, HashSet};
+use std::future::Future;
 use std::sync::Arc;
 use tokio::sync::broadcast;
 use tokio::sync::oneshot;
@@ -443,10 +445,11 @@ impl AsyncPgConnection {
     async fn set_config_options(&mut self) -> QueryResult<()> {
         use crate::run_query_dsl::RunQueryDsl;
 
-        futures_util::try_join!(
+        futures_util::future::try_join(
             diesel::sql_query("SET TIME ZONE 'UTC'").execute(self),
             diesel::sql_query("SET CLIENT_ENCODING TO 'UTF8'").execute(self),
-        )?;
+        )
+        .await?;
         Ok(())
     }
 

src/pooled_connection/mod.rs

@@ -10,8 +10,8 @@ use crate::{TransactionManager, UpdateAndFetchResults};
 use diesel::associations::HasTable;
 use diesel::connection::{CacheSize, Instrumentation};
 use diesel::QueryResult;
-use futures_util::future::BoxFuture;
-use futures_util::{future, FutureExt};
+use futures_core::future::BoxFuture;
+use futures_util::FutureExt;
 use std::borrow::Cow;
 use std::fmt;
 use std::future::Future;
@@ -47,11 +47,10 @@ impl std::error::Error for PoolError {}
 
 /// Type of the custom setup closure passed to [`ManagerConfig::custom_setup`]
 pub type SetupCallback<C> =
-    Box<dyn Fn(&str) -> future::BoxFuture<diesel::ConnectionResult<C>> + Send + Sync>;
+    Box<dyn Fn(&str) -> BoxFuture<diesel::ConnectionResult<C>> + Send + Sync>;
 
 /// Type of the recycle check callback for the [`RecyclingMethod::CustomFunction`] variant
-pub type RecycleCheckCallback<C> =
-    dyn Fn(&mut C) -> future::BoxFuture<QueryResult<()>> + Send + Sync;
+pub type RecycleCheckCallback<C> = dyn Fn(&mut C) -> BoxFuture<QueryResult<()>> + Send + Sync;
 
 /// Possible methods of how a connection is recycled.
 #[derive(Default)]

src/run_query_dsl/mod.rs

@@ -3,8 +3,9 @@ use diesel::associations::HasTable;
 use diesel::query_builder::IntoUpdateTarget;
 use diesel::result::QueryResult;
 use diesel::AsChangeset;
-use futures_util::future::BoxFuture;
-use futures_util::{future, stream, FutureExt, Stream, StreamExt, TryFutureExt, TryStreamExt};
+use futures_core::future::BoxFuture;
+use futures_core::Stream;
+use futures_util::{future, stream, FutureExt, StreamExt, TryFutureExt, TryStreamExt};
 use std::future::Future;
 use std::pin::Pin;
 
@@ -398,7 +399,7 @@ pub trait RunQueryDsl<Conn>: Sized {
     ///     .await?
     ///     .try_fold(Vec::new(), |mut acc, item| {
     ///          acc.push(item);
-    ///          futures_util::future::ready(Ok(acc))
+    ///          std::future::ready(Ok(acc))
     ///      })
     ///     .await?;
     /// assert_eq!(vec!["Sean", "Tess"], data);
@@ -427,7 +428,7 @@ pub trait RunQueryDsl<Conn>: Sized {
     ///     .await?
     ///     .try_fold(Vec::new(), |mut acc, item| {
     ///          acc.push(item);
-    ///          futures_util::future::ready(Ok(acc))
+    ///          std::future::ready(Ok(acc))
     ///      })
     ///     .await?;
     /// let expected_data = vec![
@@ -467,7 +468,7 @@ pub trait RunQueryDsl<Conn>: Sized {
     ///     .await?
     ///     .try_fold(Vec::new(), |mut acc, item| {
     ///          acc.push(item);
-    ///          futures_util::future::ready(Ok(acc))
+    ///          std::future::ready(Ok(acc))
     ///      })
     ///     .await?;
     /// let expected_data = vec![

src/stmt_cache.rs

@@ -1,13 +1,15 @@
 use diesel::connection::statement_cache::{MaybeCached, StatementCallbackReturnType};
 use diesel::QueryResult;
-use futures_util::{future, FutureExt, TryFutureExt};
-use std::future::Future;
+use futures_core::future::BoxFuture;
+use futures_util::future::Either;
+use futures_util::{FutureExt, TryFutureExt};
+use std::future::{self, Future};
 
 pub(crate) struct CallbackHelper<F>(pub(crate) F);
 
-type PrepareFuture<'a, C, S> = future::Either<
+type PrepareFuture<'a, C, S> = Either<
     future::Ready<QueryResult<(MaybeCached<'a, S>, C)>>,
-    future::BoxFuture<'a, QueryResult<(MaybeCached<'a, S>, C)>>,
+    BoxFuture<'a, QueryResult<(MaybeCached<'a, S>, C)>>,
 >;
 
 impl<S, F, C> StatementCallbackReturnType<S, C> for CallbackHelper<F>
@@ -18,22 +20,22 @@ where
     type Return<'a> = PrepareFuture<'a, C, S>;
 
     fn from_error<'a>(e: diesel::result::Error) -> Self::Return<'a> {
-        future::Either::Left(future::ready(Err(e)))
+        Either::Left(future::ready(Err(e)))
     }
 
     fn map_to_no_cache<'a>(self) -> Self::Return<'a>
     where
         Self: 'a,
     {
-        future::Either::Right(
+        Either::Right(
             self.0
                 .map_ok(|(stmt, conn)| (MaybeCached::CannotCache(stmt), conn))
                 .boxed(),
         )
     }
 
     fn map_to_cache(stmt: &mut S, conn: C) -> Self::Return<'_> {
-        future::Either::Left(future::ready(Ok((MaybeCached::Cached(stmt), conn))))
+        Either::Left(future::ready(Ok((MaybeCached::Cached(stmt), conn))))
     }
 
     fn register_cache<'a>(
@@ -43,7 +45,7 @@ where
     where
         Self: 'a,
     {
-        future::Either::Right(
+        Either::Right(
             self.0
                 .map_ok(|(stmt, conn)| (MaybeCached::Cached(callback(stmt)), conn))
                 .boxed(),

src/sync_connection_wrapper/mod.rs

@@ -6,7 +6,7 @@
 //!
 //! * using a sync Connection implementation in async context
 //! * using the same code base for async crates needing multiple backends
-use futures_util::future::BoxFuture;
+use futures_core::future::BoxFuture;
 use std::error::Error;
 
 #[cfg(feature = "sqlite")]
@@ -100,7 +100,7 @@ mod implementation {
     };
     use diesel::row::IntoOwnedRow;
     use diesel::{ConnectionResult, QueryResult};
-    use futures_util::stream::BoxStream;
+    use futures_core::stream::BoxStream;
     use futures_util::{FutureExt, StreamExt, TryFutureExt};
     use std::marker::PhantomData;
     use std::sync::{Arc, Mutex};