attempt to fix Send guards on collect

Signed-off-by: Yoshua Wuyts <[email protected]>

Author: yoshuawuyts

src/collections/binary_heap/from_stream.rs

@@ -4,7 +4,7 @@ use std::pin::Pin;
 use crate::prelude::*;
 use crate::stream::{self, FromStream, IntoStream};
 
-impl<T: Ord> FromStream<T> for BinaryHeap<T> {
+impl<T: Ord + Send> FromStream<T> for BinaryHeap<T> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,

src/collections/btree_map/from_stream.rs

@@ -4,7 +4,7 @@ use std::pin::Pin;
 use crate::prelude::*;
 use crate::stream::{self, FromStream, IntoStream};
 
-impl<K: Ord, V> FromStream<(K, V)> for BTreeMap<K, V> {
+impl<K: Ord + Send, V: Send> FromStream<(K, V)> for BTreeMap<K, V> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = (K, V)> + 'a>(
         stream: S,

src/collections/btree_set/from_stream.rs

@@ -4,7 +4,7 @@ use std::pin::Pin;
 use crate::prelude::*;
 use crate::stream::{self, FromStream, IntoStream};
 
-impl<T: Ord> FromStream<T> for BTreeSet<T> {
+impl<T: Ord + Send> FromStream<T> for BTreeSet<T> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,

src/collections/hash_map/from_stream.rs

@@ -7,8 +7,9 @@ use crate::stream::{self, FromStream, IntoStream};
 
 impl<K, V, H> FromStream<(K, V)> for HashMap<K, V, H>
 where
-    K: Eq + Hash,
+    K: Eq + Hash + Send,
     H: BuildHasher + Default,
+    V: Send,
 {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = (K, V)> + 'a>(

src/collections/hash_set/from_stream.rs

@@ -7,7 +7,7 @@ use crate::stream::{self, FromStream, IntoStream};
 
 impl<T, H> FromStream<T> for HashSet<T, H>
 where
-    T: Eq + Hash,
+    T: Eq + Hash + Send,
     H: BuildHasher + Default,
 {
     #[inline]

src/collections/linked_list/from_stream.rs

@@ -4,7 +4,7 @@ use std::pin::Pin;
 use crate::prelude::*;
 use crate::stream::{self, FromStream, IntoStream};
 
-impl<T> FromStream<T> for LinkedList<T> {
+impl<T: Send> FromStream<T> for LinkedList<T> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,

src/collections/vec_deque/from_stream.rs

@@ -4,7 +4,7 @@ use std::pin::Pin;
 use crate::prelude::*;
 use crate::stream::{self, FromStream, IntoStream};
 
-impl<T> FromStream<T> for VecDeque<T> {
+impl<T: Send> FromStream<T> for VecDeque<T> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,

src/option/from_stream.rs

@@ -3,7 +3,7 @@ use std::pin::Pin;
 use crate::prelude::*;
 use crate::stream::{FromStream, IntoStream};
 
-impl<T, V> FromStream<Option<T>> for Option<V>
+impl<T: Send, V> FromStream<Option<T>> for Option<V>
 where
     V: FromStream<T>,
 {

src/path/pathbuf.rs

@@ -337,7 +337,7 @@ impl<P: AsRef<Path>> stream::Extend<P> for PathBuf {
 }
 
 #[cfg(feature = "unstable")]
-impl<'b, P: AsRef<Path> + 'b> FromStream<P> for PathBuf {
+impl<'b, P: AsRef<Path> + 'b + Send> FromStream<P> for PathBuf {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = P> + 'a>(
         stream: S,

src/result/from_stream.rs

@@ -5,6 +5,8 @@ use crate::stream::{FromStream, IntoStream};
 
 impl<T, E, V> FromStream<Result<T, E>> for Result<V, E>
 where
+    T: Send,
+    E: Send,
     V: FromStream<T>,
 {
     /// Takes each element in the stream: if it is an `Err`, no further

src/stream/from_stream.rs

@@ -107,12 +107,12 @@ use crate::stream::IntoStream;
 /// assert_eq!(c.0, vec![5, 5, 5, 5, 5]);
 /// #
 /// # Ok(()) }) }
-///```
+/// ```
 ///
 /// [`IntoStream`]: trait.IntoStream.html
 #[cfg(feature = "unstable")]
 #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
-pub trait FromStream<T> {
+pub trait FromStream<T: Send> {
     /// Creates a value from a stream.
     ///
     /// # Examples

src/stream/stream/mod.rs

@@ -1881,6 +1881,7 @@ extension_trait! {
         where
             Self: Sized + 'a,
             B: FromStream<Self::Item>,
+            Self::Item: Send,
         {
             FromStream::from_stream(self)
         }

src/vec/from_stream.rs

@@ -6,7 +6,7 @@ use std::sync::Arc;
 use crate::prelude::*;
 use crate::stream::{self, FromStream, IntoStream};
 
-impl<T> FromStream<T> for Vec<T> {
+impl<T: Send> FromStream<T> for Vec<T> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T>>(
         stream: S,
@@ -24,7 +24,7 @@ impl<T> FromStream<T> for Vec<T> {
     }
 }
 
-impl<'b, T: Clone> FromStream<T> for Cow<'b, [T]> {
+impl<'b, T: Clone + Send> FromStream<T> for Cow<'b, [T]> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,
@@ -37,7 +37,7 @@ impl<'b, T: Clone> FromStream<T> for Cow<'b, [T]> {
     }
 }
 
-impl<T> FromStream<T> for Box<[T]> {
+impl<T: Send> FromStream<T> for Box<[T]> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,
@@ -50,7 +50,7 @@ impl<T> FromStream<T> for Box<[T]> {
     }
 }
 
-impl<T> FromStream<T> for Rc<[T]> {
+impl<T: Send> FromStream<T> for Rc<[T]> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,
@@ -63,7 +63,7 @@ impl<T> FromStream<T> for Rc<[T]> {
     }
 }
 
-impl<T> FromStream<T> for Arc<[T]> {
+impl<T: Send> FromStream<T> for Arc<[T]> {
     #[inline]
     fn from_stream<'a, S: IntoStream<Item = T> + 'a>(
         stream: S,

tests/collect.rs

@@ -0,0 +1,18 @@
+use async_std::prelude::*;
+use async_std::io;
+use async_std::task;
+
+#[test]
+fn test_send() -> io::Result<()> {
+    task::block_on(async {
+        fn test_send_trait<T: Send>(_: &T) {}
+
+        let stream = futures::stream::pending::<()>();
+        test_send_trait(&stream);
+
+        let fut = stream.collect::<Vec<_>>();
+
+        // This line triggers a compilation error
+        test_send_trait(&fut);
+    })
+}