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rust-lang · May 14, 2019 · 7c84697 · 7c84697
1 parent 7b5c732
commit 7c84697
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Showing 11 changed files with 25 additions and 52 deletions.
diff --git a/futures-util/src/future/catch_unwind.rs b/futures-util/src/future/catch_unwind.rs
@@ -27,9 +27,6 @@ impl<Fut> Future for CatchUnwind<Fut>
     type Output = Result<Fut::Output, Box<dyn Any + Send>>;
 
     fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
-        match catch_unwind(AssertUnwindSafe(|| self.future().poll(cx))) {
-            Ok(res) => res.map(Ok),
-            Err(e) => Poll::Ready(Err(e))
-        }
+        catch_unwind(AssertUnwindSafe(|| self.future().poll(cx)))?.map(Ok)
     }
 }
diff --git a/futures-util/src/sink/buffer.rs b/futures-util/src/sink/buffer.rs
@@ -60,9 +60,7 @@ impl<Si: Sink<Item>, Item> Buffer<Si, Item> {
     ) -> Poll<Result<(), Si::SinkError>> {
         ready!(self.as_mut().sink().poll_ready(cx))?;
         while let Some(item) = self.as_mut().buf().pop_front() {
-            if let Err(e) = self.as_mut().sink().start_send(item) {
-                return Poll::Ready(Err(e));
-            }
+            self.as_mut().sink().start_send(item)?;
             if !self.buf.is_empty() {
                 ready!(self.as_mut().sink().poll_ready(cx))?;
             }
@@ -91,9 +89,7 @@ impl<Si: Sink<Item>, Item> Sink<Item> for Buffer<Si, Item> {
             return self.as_mut().sink().poll_ready(cx);
         }
 
-        if let Poll::Ready(Err(e)) = self.as_mut().try_empty_buffer(cx) {
-            return Poll::Ready(Err(e));
-        }
+        let _ = self.as_mut().try_empty_buffer(cx)?;
 
         if self.buf.len() >= self.capacity {
             Poll::Pending

diff --git a/futures-util/src/sink/send.rs b/futures-util/src/sink/send.rs
@@ -33,13 +33,8 @@ impl<Si: Sink<Item> + Unpin + ?Sized, Item> Future for Send<'_, Si, Item> {
         let this = &mut *self;
         if let Some(item) = this.item.take() {
             let mut sink = Pin::new(&mut this.sink);
-            match sink.as_mut().poll_ready(cx) {
-                Poll::Ready(Ok(())) => {
-                    if let Err(e) = sink.as_mut().start_send(item) {
-                        return Poll::Ready(Err(e));
-                    }
-                }
-                Poll::Ready(Err(e)) => return Poll::Ready(Err(e)),
+            match sink.as_mut().poll_ready(cx)? {
+                Poll::Ready(()) => sink.as_mut().start_send(item)?,
                 Poll::Pending => {
                     this.item = Some(item);
                     return Poll::Pending;

diff --git a/futures-util/src/sink/send_all.rs b/futures-util/src/sink/send_all.rs
@@ -47,11 +47,10 @@ where
         item: St::Item,
     ) -> Poll<Result<(), Si::SinkError>> {
         debug_assert!(self.buffered.is_none());
-        match Pin::new(&mut self.sink).poll_ready(cx) {
-            Poll::Ready(Ok(())) => {
+        match Pin::new(&mut self.sink).poll_ready(cx)? {
+            Poll::Ready(()) => {
                 Poll::Ready(Pin::new(&mut self.sink).start_send(item))
             }
-            Poll::Ready(Err(e)) => Poll::Ready(Err(e)),
             Poll::Pending => {
                 self.buffered = Some(item);
                 Poll::Pending

diff --git a/futures-util/src/sink/with_flat_map.rs b/futures-util/src/sink/with_flat_map.rs
@@ -146,21 +146,15 @@ where
         mut self: Pin<&mut Self>,
         cx: &mut Context<'_>,
     ) -> Poll<Result<(), Self::SinkError>> {
-        match self.as_mut().try_empty_stream(cx) {
-            Poll::Pending => Poll::Pending,
-            Poll::Ready(Ok(())) => self.as_mut().sink().poll_flush(cx),
-            Poll::Ready(Err(e)) => Poll::Ready(Err(e)),
-        }
+        ready!(self.as_mut().try_empty_stream(cx)?);
+        self.as_mut().sink().poll_flush(cx)
     }
 
     fn poll_close(
         mut self: Pin<&mut Self>,
         cx: &mut Context<'_>,
     ) -> Poll<Result<(), Self::SinkError>> {
-        match self.as_mut().try_empty_stream(cx) {
-            Poll::Pending => Poll::Pending,
-            Poll::Ready(Ok(())) => self.as_mut().sink().poll_close(cx),
-            Poll::Ready(Err(e)) => Poll::Ready(Err(e)),
-        }
+        ready!(self.as_mut().try_empty_stream(cx)?);
+        self.as_mut().sink().poll_close(cx)
     }
 }
diff --git a/futures-util/src/stream/forward.rs b/futures-util/src/stream/forward.rs
@@ -77,10 +77,9 @@ where
         }
 
         loop {
-            match self.as_mut().stream().poll_next(cx) {
-                Poll::Ready(Some(Ok(item))) =>
+            match self.as_mut().stream().poll_next(cx)? {
+                Poll::Ready(Some(item)) =>
                    ready!(self.as_mut().try_start_send(cx, item))?,
-                Poll::Ready(Some(Err(e))) => return Poll::Ready(Err(e)),
                 Poll::Ready(None) => {
                     ready!(self.as_mut().sink().as_pin_mut().expect(INVALID_POLL).poll_close(cx))?;
                     self.as_mut().sink().set(None);

diff --git a/futures-util/src/try_stream/try_buffer_unordered.rs b/futures-util/src/try_stream/try_buffer_unordered.rs
@@ -85,9 +85,8 @@ impl<St> Stream for TryBufferUnordered<St>
         // First up, try to spawn off as many futures as possible by filling up
         // our slab of futures. Propagate errors from the stream immediately.
         while self.in_progress_queue.len() < self.max {
-            match self.as_mut().stream().poll_next(cx) {
-                Poll::Ready(Some(Ok(fut))) => self.as_mut().in_progress_queue().push(fut.into_future()),
-                Poll::Ready(Some(Err(e))) => return Poll::Ready(Some(Err(e))),
+            match self.as_mut().stream().poll_next(cx)? {
+                Poll::Ready(Some(fut)) => self.as_mut().in_progress_queue().push(fut.into_future()),
                 Poll::Ready(None) | Poll::Pending => break,
             }
         }

diff --git a/futures-util/src/try_stream/try_collect.rs b/futures-util/src/try_stream/try_collect.rs
@@ -47,9 +47,8 @@ impl<St, C> Future for TryCollect<St, C>
         cx: &mut Context<'_>,
     ) -> Poll<Self::Output> {
         loop {
-            match ready!(self.as_mut().stream().try_poll_next(cx)) {
-                Some(Ok(x)) => self.as_mut().items().extend(Some(x)),
-                Some(Err(e)) => return Poll::Ready(Err(e)),
+            match ready!(self.as_mut().stream().try_poll_next(cx)?) {
+                Some(x) => self.as_mut().items().extend(Some(x)),
                 None => return Poll::Ready(Ok(self.as_mut().finish())),
             }
         }

diff --git a/futures-util/src/try_stream/try_concat.rs b/futures-util/src/try_stream/try_concat.rs
@@ -40,16 +40,15 @@ where
 
     fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         loop {
-            match ready!(self.as_mut().stream().try_poll_next(cx)) {
-                Some(Ok(x)) => {
+            match ready!(self.as_mut().stream().try_poll_next(cx)?) {
+                Some(x) => {
                     let accum = self.as_mut().accum();
                     if let Some(a) = accum {
                         a.extend(x)
                     } else {
                         *accum = Some(x)
                     }
                 },
-                Some(Err(e)) => return Poll::Ready(Err(e)),
                 None => {
                     return Poll::Ready(Ok(self.as_mut().accum().take().unwrap_or_default()))
                 }

diff --git a/futures-util/src/try_stream/try_filter.rs b/futures-util/src/try_stream/try_filter.rs
@@ -95,9 +95,8 @@ impl<St, Fut, F> Stream for TryFilter<St, Fut, F>
     ) -> Poll<Option<Result<St::Ok, St::Error>>> {
         loop {
             if self.pending_fut.is_none() {
-                let item = match ready!(self.as_mut().stream().try_poll_next(cx)) {
-                    Some(Ok(x)) => x,
-                    Some(Err(e)) => return Poll::Ready(Some(Err(e))),
+                let item = match ready!(self.as_mut().stream().try_poll_next(cx)?) {
+                    Some(x) => x,
                     None => return Poll::Ready(None),
                 };
                 let fut = (self.as_mut().f())(&item);

diff --git a/futures-util/src/try_stream/try_filter_map.rs b/futures-util/src/try_stream/try_filter_map.rs
@@ -84,9 +84,8 @@ impl<St, Fut, F, T> Stream for TryFilterMap<St, Fut, F>
     ) -> Poll<Option<Result<T, St::Error>>> {
         loop {
             if self.pending.is_none() {
-                let item = match ready!(self.as_mut().stream().try_poll_next(cx)) {
-                    Some(Ok(x)) => x,
-                    Some(Err(e)) => return Poll::Ready(Some(Err(e))),
+                let item = match ready!(self.as_mut().stream().try_poll_next(cx)?) {
+                    Some(x) => x,
                     None => return Poll::Ready(None),
                 };
                 let fut = (self.as_mut().f())(item);
@@ -95,10 +94,8 @@ impl<St, Fut, F, T> Stream for TryFilterMap<St, Fut, F>
 
             let result = ready!(self.as_mut().pending().as_pin_mut().unwrap().try_poll(cx));
             self.as_mut().pending().set(None);
-            match result {
-                Ok(Some(x)) => return Poll::Ready(Some(Ok(x))),
-                Err(e) => return Poll::Ready(Some(Err(e))),
-                Ok(None) => {},
+            if let Some(x) = result? {
+                return Poll::Ready(Some(Ok(x)));
             }
         }
     }