chore: Disable unused futures feature

Author: tottoto

Cargo.toml

@@ -8,7 +8,7 @@ members = [
 ]
 
 [workspace.dependencies]
-futures = "0.3.22"
+futures = { version = "0.3.22", default-features = false }
 futures-core = "0.3.22"
 futures-util = { version = "0.3.22", default-features = false }
 hdrhistogram = { version = "7.0", default-features = false }

tower-service/Cargo.toml

@@ -25,4 +25,3 @@ edition = "2018"
 http = { workspace = true }
 tower-layer = { version = "0.3", path = "../tower-layer" }
 tokio = { workspace = true, features = ["macros", "time"] }
-futures = { workspace = true }

tower-service/src/lib.rs

@@ -17,6 +17,9 @@
 
 extern crate alloc;
 
+#[cfg(doc)]
+extern crate std;
+
 use alloc::boxed::Box;
 
 use core::future::Future;
@@ -123,7 +126,6 @@ use core::task::{Context, Poll};
 /// ```rust
 /// use tower_service::Service;
 /// use tower_layer::Layer;
-/// use futures::FutureExt;
 /// use std::future::Future;
 /// use std::task::{Context, Poll};
 /// use std::time::Duration;
@@ -332,7 +334,7 @@ pub trait Service<Request> {
     /// If the service is at capacity, then `Poll::Pending` is returned and the task
     /// is notified when the service becomes ready again. This function is
     /// expected to be called while on a task. Generally, this can be done with
-    /// a simple `futures::future::poll_fn` call.
+    /// a simple [`std::future::poll_fn`] call.
     ///
     /// If `Poll::Ready(Err(_))` is returned, the service is no longer able to service requests
     /// and the caller should discard the service instance.

tower/Cargo.toml

@@ -74,7 +74,8 @@ pin-project-lite = { workspace = true, optional = true }
 sync_wrapper = { workspace = true, optional = true }
 
 [dev-dependencies]
-futures = { workspace = true }
+futures = { workspace = true, features = ["std"] }
+futures-util = { workspace = true, features = ["async-await-macro"] }
 hdrhistogram = { workspace = true }
 tokio = { workspace = true, features = ["macros", "sync", "test-util", "rt-multi-thread"] }
 tokio-stream = { workspace = true }