impl std::io::Write for SmallVec

lib.rs

@@ -33,6 +33,8 @@ use std::mem;
 use std::ops;
 use std::ptr;
 use std::slice;
+#[cfg(feature = "std")]
+use std::io;
 #[cfg(feature="heapsizeof")]
 use std::os::raw::c_void;
 
@@ -632,6 +634,26 @@ impl<A: Array> BorrowMut<[A::Item]> for SmallVec<A> {
  }
 }
 
+#[cfg(feature = "std")]
+impl<A: Array<Item = u8>> io::Write for SmallVec<A> {
+ #[inline]
+ fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+ self.extend_from_slice(buf);
+ Ok(buf.len())
+ }
+
+ #[inline]
+ fn write_all(&mut self, buf: &[u8]) -> io::Result<()> {
+ self.extend_from_slice(buf);
+ Ok(())
+ }
+
+ #[inline]
+ fn flush(&mut self) -> io::Result<()> {
+ Ok(())
+ }
+}
+
 impl<'a, A: Array> From<&'a [A::Item]> for SmallVec<A> where A::Item: Clone {
  #[inline]
  fn from(slice: &'a [A::Item]) -> SmallVec<A> {
@@ -1436,4 +1458,21 @@ pub mod tests {
  assert_eq!(&*small_vec, &[1, 2, 3, 4, 5]);
  drop(small_vec);
  }
+
+ #[cfg(feature = "std")]
+ #[test]
+ fn test_write() {
+ use io::Write;
+
+ let data = [1, 2, 3, 4, 5];
+
+ let mut small_vec: SmallVec<[u8; 2]> = SmallVec::new();
+ let len = small_vec.write(&data[..]).unwrap();
+ assert_eq!(len, 5);
+ assert_eq!(small_vec.as_ref(), data.as_ref());
+
+ let mut small_vec: SmallVec<[u8; 2]> = SmallVec::new();
+ small_vec.write_all(&data[..]).unwrap();
+ assert_eq!(small_vec.as_ref(), data.as_ref());
+ }
 }