Implement Stream::size_hint() for Either (#2325)

benkay86 · web-flow · commit aa784fc778ec · 2021-01-19T11:37:28.000+09:00
diff --git a/futures-util/src/future/either.rs b/futures-util/src/future/either.rs
@@ -101,6 +101,13 @@ where
             Either::Right(x) => x.poll_next(cx),
         }
     }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        match self {
+            Either::Left(x) => x.size_hint(),
+            Either::Right(x) => x.size_hint(),
+        }
+    }
 }
 
 impl<A, B> FusedStream for Either<A, B>

Original file line number	Diff line number	Diff line change
`@@ -101,6 +101,13 @@ where`
`101`	`101`	`Either::Right(x) => x.poll_next(cx),`
`102`	`102`	`}`
`103`	`103`	`}`
	`104`	`+`
	`105`	`+ fn size_hint(&self) -> (usize, Option<usize>) {`
	`106`	`+ match self {`
	`107`	`+ Either::Left(x) => x.size_hint(),`
	`108`	`+ Either::Right(x) => x.size_hint(),`
	`109`	`+ }`
	`110`	`+ }`
`104`	`111`	`}`
`105`	`112`
`106`	`113`	`impl<A, B> FusedStream for Either<A, B>`