Use async/await in a few places and reduce dependencies as a result

gstreamer-video/Cargo.toml

@@ -23,7 +23,6 @@ gst = { package = "gstreamer", path = "../gstreamer" }
 gst-base = { package = "gstreamer-base", path = "../gstreamer-base" }
 once_cell = "1.0"
 futures-channel = "0.3"
-futures-util = "0.3"
 
 [build-dependencies]
 gstreamer-rs-lgpl-docs = { path = "../docs", optional = true }

gstreamer-video/src/functions.rs

@@ -109,14 +109,12 @@ pub fn convert_sample_future(
     skip_assert_initialized!();
 
     use futures_channel::oneshot;
-    use futures_util::future::lazy;
-    use futures_util::future::FutureExt;
 
     let (sender, receiver) = oneshot::channel();
 
     let sample = sample.clone();
     let caps = caps.clone();
-    let future = lazy(move |_| {
+    let future = async move {
         assert!(
             glib::MainContext::ref_thread_default().is_owner(),
             "Spawning futures only allowed if the thread is owning the MainContext"
@@ -125,8 +123,11 @@ pub fn convert_sample_future(
         convert_sample_async(&sample, &caps, timeout, move |res| {
             let _ = sender.send(res);
         });
-    })
+
-    .then(|_| receiver.map(|res| res.expect("Sender dropped before callback was called")));
+        receiver
+            .await
+            .expect("Sender dropped before callback was called")
+    };
 
     Box::pin(future)
 }

gstreamer/Cargo.toml

@@ -22,8 +22,8 @@ glib = { git = "https://github.com/gtk-rs/gtk-rs" }
 num-rational = { version = "0.3", default-features = false, features = [] }
 once_cell = "1.0"
 futures-core = "0.3"
-futures-util = "0.3"
 futures-channel = "0.3"
+futures-util = { version = "0.3", default-features = false }
 muldiv = "1"
 serde = { version = "1.0", optional = true }
 serde_bytes = { version = "0.11", optional = true }

gstreamer/src/clock.rs

@@ -174,18 +174,10 @@ impl SingleShotClockId {
     pub fn wait_async_future(
         &self,
     ) -> Result<
-        Pin<
+        Pin<Box<dyn Future<Output = Result<(ClockTime, ClockId), ClockError>> + Send + 'static>>,
-            Box<
-                dyn Future<Output = Result<(ClockTime, ClockId), ClockError>>
-                    + Unpin
-                    + Send
-                    + 'static,
-            >,
-        >,
         ClockError,
     > {
         use futures_channel::oneshot;
-        use futures_util::TryFutureExt;
 
         let (sender, receiver) = oneshot::channel();
 
@@ -196,7 +188,9 @@ impl SingleShotClockId {
             }
         })?;
 
-        Ok(Box::pin(receiver.map_err(|_| ClockError::Unscheduled)))
+        Ok(Box::pin(async move {
+            receiver.await.map_err(|_| ClockError::Unscheduled)
+        }))
     }
 }
 

gstreamer/src/element.rs

@@ -36,9 +36,6 @@ use std::ffi::CStr;
 #[cfg(any(feature = "v1_10", feature = "dox"))]
 #[cfg_attr(feature = "dox", doc(cfg(feature = "v1_10")))]
 use std::future::Future;
-#[cfg(any(feature = "v1_10", feature = "dox"))]
-#[cfg_attr(feature = "dox", doc(cfg(feature = "v1_10")))]
-use std::marker::Unpin;
 use std::mem;
 use std::num::NonZeroU64;
 #[cfg(any(feature = "v1_10", feature = "dox"))]
@@ -262,10 +259,7 @@ pub trait ElementExtManual: 'static {
 
     #[cfg(any(feature = "v1_10", feature = "dox"))]
     #[cfg_attr(feature = "dox", doc(cfg(feature = "v1_10")))]
-    fn call_async_future<F, T>(
+    fn call_async_future<F, T>(&self, func: F) -> Pin<Box<dyn Future<Output = T> + Send + 'static>>
-        &self,
-        func: F,
-    ) -> Pin<Box<dyn Future<Output = T> + Unpin + Send + 'static>>
     where
         F: FnOnce(&Self) -> T + Send + 'static,
         T: Send + 'static;
@@ -810,16 +804,12 @@ impl<O: IsA<Element>> ElementExtManual for O {
 
     #[cfg(any(feature = "v1_10", feature = "dox"))]
     #[cfg_attr(feature = "dox", doc(cfg(feature = "v1_10")))]
-    fn call_async_future<F, T>(
+    fn call_async_future<F, T>(&self, func: F) -> Pin<Box<dyn Future<Output = T> + Send + 'static>>
-        &self,
-        func: F,
-    ) -> Pin<Box<dyn Future<Output = T> + Unpin + Send + 'static>>
     where
         F: FnOnce(&Self) -> T + Send + 'static,
         T: Send + 'static,
     {
         use futures_channel::oneshot;
-        use futures_util::future::FutureExt;
 
         let (sender, receiver) = oneshot::channel();
 
@@ -827,7 +817,7 @@ impl<O: IsA<Element>> ElementExtManual for O {
             let _ = sender.send(func(element));
         });
 
-        Box::pin(receiver.map(|res| res.expect("sender dropped")))
+        Box::pin(async move { receiver.await.expect("sender dropped") })
     }
 
     fn get_current_running_time(&self) -> crate::ClockTime {