add feature guards for unstable features

Signed-off-by: Yoshua Wuyts <yoshuawuyts@gmail.com>

src/future/timeout.rs

@@ -29,6 +29,7 @@ use crate::task::{Context, Poll};
 /// # Ok(()) }) }
 /// ```
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
+#[cfg(feature = "unstable")]
 pub async fn timeout<F, T>(dur: Duration, f: F) -> Result<T, TimeoutError>
 where
     F: Future<Output = T>,
@@ -69,6 +70,7 @@ impl<F: Future> Future for TimeoutFuture<F> {
 
 /// An error returned when a future times out.
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
+#[cfg(feature = "unstable")]
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub struct TimeoutError {
     _private: (),

src/lib.rs

@@ -42,17 +42,24 @@
 #![doc(test(attr(allow(unused_extern_crates, unused_variables))))]
 #![doc(html_logo_url = "https://async.rs/images/logo--hero.svg")]
 
+use cfg_if::cfg_if;
+
 pub mod fs;
 pub mod future;
 pub mod io;
 pub mod net;
 pub mod os;
 pub mod prelude;
-mod result;
 pub mod stream;
 pub mod sync;
 pub mod task;
-mod vec;
+
+cfg_if! {
+    if #[cfg(any(feature = "unstable", feature = "docs"))] {
+        mod vec;
+        mod result;
+    }
+}
 
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
 #[cfg(feature = "unstable")]

src/stream/double_ended_stream.rs

@@ -11,6 +11,7 @@ use std::task::{Context, Poll};
 ///
 /// [`Stream`]: trait.Stream.html
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
+#[cfg(feature = "unstable")]
 pub trait DoubleEndedStream: Stream {
     /// Removes and returns an element from the end of the stream.
     ///

src/stream/from_stream.rs

@@ -11,6 +11,7 @@ use std::pin::Pin;
 ///
 /// [`IntoStream`]: trait.IntoStream.html
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
+#[cfg(feature = "unstable")]
 pub trait FromStream<T: Send> {
     /// Creates a value from a stream.
     ///

src/stream/into_stream.rs

@@ -14,6 +14,7 @@ use futures_core::stream::Stream;
 ///
 /// [`FromStream`]: trait.FromStream.html
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
+#[cfg(feature = "unstable")]
 pub trait IntoStream {
     /// The type of the elements being iterated over.
     type Item;

src/stream/mod.rs

@@ -21,18 +21,26 @@
 //! # }) }
 //! ```
 
-pub use double_ended_stream::DoubleEndedStream;
+use cfg_if::cfg_if;
+
 pub use empty::{empty, Empty};
-pub use from_stream::FromStream;
-pub use into_stream::IntoStream;
 pub use once::{once, Once};
 pub use repeat::{repeat, Repeat};
 pub use stream::{Fuse, Scan, Stream, Take, Zip};
 
-mod double_ended_stream;
 mod empty;
-mod from_stream;
-mod into_stream;
 mod once;
 mod repeat;
 mod stream;
+
+cfg_if! {
+    if #[cfg(any(feature = "unstable", feature = "docs"))] {
+        mod double_ended_stream;
+        mod from_stream;
+        mod into_stream;
+
+        pub use double_ended_stream::DoubleEndedStream;
+        pub use from_stream::FromStream;
+        pub use into_stream::IntoStream;
+    }
+}

src/stream/stream/mod.rs

@@ -52,7 +52,6 @@ use min_by::MinByFuture;
 use next::NextFuture;
 use nth::NthFuture;
 
-use super::from_stream::FromStream;
 use std::cmp::Ordering;
 use std::marker::PhantomData;
 use std::pin::Pin;
@@ -60,6 +59,12 @@ use std::task::{Context, Poll};
 
 use cfg_if::cfg_if;
 
+cfg_if! {
+    if #[cfg(any(feature = "unstable", feature = "docs"))] {
+        use crate::stream::FromStream;
+    }
+}
+
 cfg_if! {
     if #[cfg(feature = "docs")] {
         #[doc(hidden)]
@@ -748,6 +753,8 @@ pub trait Stream {
     ///
     /// [`stream`]: trait.Stream.html#tymethod.next
     #[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead (TODO)"]
+    #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
+    #[cfg(feature = "unstable")]
     fn collect<'a, B>(self) -> dyn_ret!('a, B)
     where
         Self: futures_core::stream::Stream + Sized + Send + 'a,