Remove io::Cursor, and implement Buf/BufMut for slices instead (#261)

benches/buf.rs

@@ -5,7 +5,6 @@ extern crate test;
 
 use test::Bencher;
 use bytes::Buf;
-use std::io::Cursor;
 
 /// Dummy Buf implementation
 struct TestBuf {
@@ -120,7 +119,7 @@ macro_rules! bench {
         #[bench]
         fn $fname(b: &mut Bencher) {
             // buf must be long enough for one read of 8 bytes starting at pos 7
-            let mut buf = Cursor::new(vec![1u8; 8+7]);
+            let mut buf = [1u8; 8+7];
             b.iter(|| {
                 for i in 0..8 {
                     buf.set_position(i);

src/buf/buf.rs

@@ -2,7 +2,7 @@ use super::{IntoBuf, Take, Reader, FromBuf, Chain};
 use byteorder::{BigEndian, ByteOrder, LittleEndian};
 use iovec::IoVec;
 
-use std::{cmp, io, ptr};
+use std::{cmp, ptr};
 
 macro_rules! buf_get_impl {
     ($this:ident, $size:expr, $conv:path) => ({
@@ -44,13 +44,12 @@ macro_rules! buf_get_impl {
 /// position. It can be thought of as an efficient `Iterator` for collections of
 /// bytes.
 ///
-/// The simplest `Buf` is a `Cursor` wrapping a `[u8]`.
+/// The simplest `Buf` is a `&[u8]`.
 ///
 /// ```
-/// use bytes::{Buf, Bytes};
-/// use std::io::Cursor;
+/// use bytes::Buf;
 ///
-/// let mut buf = Bytes::from_static(b"hello world");
+/// let mut buf = &b"hello world"[..];
 ///
 /// assert_eq!(b'h', buf.get_u8());
 /// assert_eq!(b'e', buf.get_u8());
@@ -59,7 +58,7 @@ macro_rules! buf_get_impl {
 /// let mut rest = [0; 8];
 /// buf.copy_to_slice(&mut rest);
 ///
-/// assert_eq!(&rest[..], b"lo world");
+/// assert_eq!(&rest[..], &b"lo world"[..]);
 /// ```
 pub trait Buf {
     /// Returns the number of bytes between the current position and the end of
@@ -71,9 +70,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"hello world");
+    /// let mut buf = &b"hello world"[..];
     ///
     /// assert_eq!(buf.remaining(), 11);
     ///
@@ -99,15 +98,15 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"hello world");
+    /// let mut buf = &b"hello world"[..];
     ///
-    /// assert_eq!(buf.bytes(), b"hello world");
+    /// assert_eq!(buf.bytes(), &b"hello world"[..]);
     ///
     /// buf.advance(6);
     ///
-    /// assert_eq!(buf.bytes(), b"world");
+    /// assert_eq!(buf.bytes(), &b"world"[..]);
     /// ```
     ///
     /// # Implementer notes
@@ -165,15 +164,15 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"hello world");
+    /// let mut buf = &b"hello world"[..];
     ///
-    /// assert_eq!(buf.bytes(), b"hello world");
+    /// assert_eq!(buf.bytes(), &b"hello world"[..]);
     ///
     /// buf.advance(6);
     ///
-    /// assert_eq!(buf.bytes(), b"world");
+    /// assert_eq!(buf.bytes(), &b"world"[..]);
     /// ```
     ///
     /// # Panics
@@ -196,9 +195,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"a");
+    /// let mut buf = &b"a"[..];
     ///
     /// assert!(buf.has_remaining());
     ///
@@ -218,13 +217,13 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"hello world");
+    /// let mut buf = &b"hello world"[..];
     /// let mut dst = [0; 5];
     ///
     /// buf.copy_to_slice(&mut dst);
-    /// assert_eq!(b"hello", &dst);
+    /// assert_eq!(&b"hello"[..], &dst);
     /// assert_eq!(6, buf.remaining());
     /// ```
     ///
@@ -260,9 +259,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08 hello");
+    /// let mut buf = &b"\x08 hello"[..];
     /// assert_eq!(8, buf.get_u8());
     /// ```
     ///
@@ -283,9 +282,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08 hello");
+    /// let mut buf = &b"\x08 hello"[..];
     /// assert_eq!(8, buf.get_i8());
     /// ```
     ///
@@ -306,9 +305,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08\x09 hello");
+    /// let mut buf = &b"\x08\x09 hello"[..];
     /// assert_eq!(0x0809, buf.get_u16());
     /// ```
     ///
@@ -326,9 +325,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x09\x08 hello");
+    /// let mut buf = &b"\x09\x08 hello"[..];
     /// assert_eq!(0x0809, buf.get_u16_le());
     /// ```
     ///
@@ -346,9 +345,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08\x09 hello");
+    /// let mut buf = &b"\x08\x09 hello"[..];
     /// assert_eq!(0x0809, buf.get_i16());
     /// ```
     ///
@@ -366,9 +365,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x09\x08 hello");
+    /// let mut buf = &b"\x09\x08 hello"[..];
     /// assert_eq!(0x0809, buf.get_i16_le());
     /// ```
     ///
@@ -386,9 +385,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08\x09\xA0\xA1 hello");
+    /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..];
     /// assert_eq!(0x0809A0A1, buf.get_u32());
     /// ```
     ///
@@ -406,9 +405,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\xA1\xA0\x09\x08 hello");
+    /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..];
     /// assert_eq!(0x0809A0A1, buf.get_u32_le());
     /// ```
     ///
@@ -426,9 +425,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08\x09\xA0\xA1 hello");
+    /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..];
     /// assert_eq!(0x0809A0A1, buf.get_i32());
     /// ```
     ///
@@ -446,9 +445,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\xA1\xA0\x09\x08 hello");
+    /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..];
     /// assert_eq!(0x0809A0A1, buf.get_i32_le());
     /// ```
     ///
@@ -466,9 +465,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x01\x02\x03\x04\x05\x06\x07\x08 hello");
+    /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..];
     /// assert_eq!(0x0102030405060708, buf.get_u64());
     /// ```
     ///
@@ -486,9 +485,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08\x07\x06\x05\x04\x03\x02\x01 hello");
+    /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
     /// assert_eq!(0x0102030405060708, buf.get_u64_le());
     /// ```
     ///
@@ -506,9 +505,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x01\x02\x03\x04\x05\x06\x07\x08 hello");
+    /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..];
     /// assert_eq!(0x0102030405060708, buf.get_i64());
     /// ```
     ///
@@ -526,9 +525,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x08\x07\x06\x05\x04\x03\x02\x01 hello");
+    /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
     /// assert_eq!(0x0102030405060708, buf.get_i64_le());
     /// ```
     ///
@@ -548,9 +547,8 @@ pub trait Buf {
     ///
     /// ```
     /// use bytes::Buf;
-    /// use std::io::Cursor;
     ///
-    /// let mut buf = Cursor::new(b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello");
+    /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello"[..];
     /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128());
     /// ```
     ///
@@ -571,9 +569,8 @@ pub trait Buf {
     ///
     /// ```
     /// use bytes::Buf;
-    /// use std::io::Cursor;
     ///
-    /// let mut buf = Cursor::new(b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello");
+    /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
     /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128_le());
     /// ```
     ///
@@ -594,9 +591,8 @@ pub trait Buf {
     ///
     /// ```
     /// use bytes::Buf;
-    /// use std::io::Cursor;
     ///
-    /// let mut buf = Cursor::new(b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello");
+    /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello"[..];
     /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128());
     /// ```
     ///
@@ -617,9 +613,8 @@ pub trait Buf {
     ///
     /// ```
     /// use bytes::Buf;
-    /// use std::io::Cursor;
     ///
-    /// let mut buf = Cursor::new(b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello");
+    /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
     /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128_le());
     /// ```
     ///
@@ -638,9 +633,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x01\x02\x03 hello");
+    /// let mut buf = &b"\x01\x02\x03 hello"[..];
     /// assert_eq!(0x010203, buf.get_uint(3));
     /// ```
     ///
@@ -658,9 +653,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x03\x02\x01 hello");
+    /// let mut buf = &b"\x03\x02\x01 hello"[..];
     /// assert_eq!(0x010203, buf.get_uint_le(3));
     /// ```
     ///
@@ -678,9 +673,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x01\x02\x03 hello");
+    /// let mut buf = &b"\x01\x02\x03 hello"[..];
     /// assert_eq!(0x010203, buf.get_int(3));
     /// ```
     ///
@@ -698,9 +693,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x03\x02\x01 hello");
+    /// let mut buf = &b"\x03\x02\x01 hello"[..];
     /// assert_eq!(0x010203, buf.get_int_le(3));
     /// ```
     ///
@@ -719,9 +714,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x3F\x99\x99\x9A hello");
+    /// let mut buf = &b"\x3F\x99\x99\x9A hello"[..];
     /// assert_eq!(1.2f32, buf.get_f32());
     /// ```
     ///
@@ -740,9 +735,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x9A\x99\x99\x3F hello");
+    /// let mut buf = &b"\x9A\x99\x99\x3F hello"[..];
     /// assert_eq!(1.2f32, buf.get_f32_le());
     /// ```
     ///
@@ -761,9 +756,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello");
+    /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello"[..];
     /// assert_eq!(1.2f64, buf.get_f64());
     /// ```
     ///
@@ -782,9 +777,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"\x33\x33\x33\x33\x33\x33\xF3\x3F hello");
+    /// let mut buf = &b"\x33\x33\x33\x33\x33\x33\xF3\x3F hello"[..];
     /// assert_eq!(1.2f64, buf.get_f64_le());
     /// ```
     ///
@@ -805,12 +800,12 @@ pub trait Buf {
     /// Collecting a buffer and loading the contents into a `Vec<u8>`.
     ///
     /// ```
-    /// use bytes::{Buf, Bytes, IntoBuf};
+    /// use bytes::Buf;
     ///
-    /// let buf = Bytes::from(&b"hello world"[..]).into_buf();
+    /// let buf = &b"hello world"[..];
     /// let vec: Vec<u8> = buf.collect();
     ///
-    /// assert_eq!(vec, &b"hello world"[..]);
+    /// assert_eq!(vec, b"hello world");
     /// ```
     fn collect<B>(self) -> B
         where Self: Sized,
@@ -827,9 +822,9 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, BufMut, Bytes};
+    /// use bytes::{Buf, BufMut};
     ///
-    /// let mut buf = Bytes::from_static(b"hello world").take(5);
+    /// let mut buf = b"hello world"[..].take(5);
     /// let mut dst = vec![];
     ///
     /// dst.put(&mut buf);
@@ -854,14 +849,12 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Bytes, Buf};
-    /// use bytes::buf::Chain;
+    /// use bytes::Buf;
     ///
-    /// let chain = Bytes::from_static(b"hello ")
-    ///             .chain(Bytes::from(&b"world"[..]));
+    /// let chain = b"hello "[..].chain(&b"world"[..]);
     ///
-    /// let full: Bytes = chain.collect();
-    /// assert_eq!(full[..], b"hello world"[..]);
+    /// let full: Vec<u8> = chain.collect();
+    /// assert_eq!(full, b"hello world");
     /// ```
     fn chain<U>(self, next: U) -> Chain<Self, U::Buf>
         where U: IntoBuf,
@@ -877,20 +870,20 @@ pub trait Buf {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{Buf, BufMut, Bytes};
+    /// use bytes::{Buf, BufMut};
     ///
-    /// let mut buf = Bytes::from_static(b"hello world");
+    /// let mut buf = &b"hello world"[..];
     /// let mut dst = vec![];
     ///
     /// {
     ///     let mut reference = buf.by_ref();
     ///     dst.put(&mut reference.take(5));
-    ///     assert_eq!(dst, b"hello");
+    ///     assert_eq!(dst, &b"hello"[..]);
     /// } // drop our &mut reference so we can use `buf` again
     ///
     /// dst.clear();
     /// dst.put(&mut buf);
-    /// assert_eq!(dst, b" world");
+    /// assert_eq!(dst, &b" world"[..]);
     /// ```
     fn by_ref(&mut self) -> &mut Self where Self: Sized {
         self
@@ -917,7 +910,7 @@ pub trait Buf {
     /// let num = reader.read(&mut dst).unwrap();
     ///
     /// assert_eq!(11, num);
-    /// assert_eq!(&dst[..11], b"hello world");
+    /// assert_eq!(&dst[..11], &b"hello world"[..]);
     /// ```
     fn reader(self) -> Reader<Self> where Self: Sized {
         super::reader::new(self)
@@ -960,36 +953,20 @@ impl<T: Buf + ?Sized> Buf for Box<T> {
     }
 }
 
-impl<T: AsRef<[u8]>> Buf for io::Cursor<T> {
+impl<'a> Buf for &'a [u8] {
+    #[inline]
     fn remaining(&self) -> usize {
-        let len = self.get_ref().as_ref().len();
-        let pos = self.position();
-
-        if pos >= len as u64 {
-            return 0;
-        }
-
-        len - pos as usize
+        self.len()
     }
 
+    #[inline]
     fn bytes(&self) -> &[u8] {
-        let len = self.get_ref().as_ref().len();
-        let pos = self.position() as usize;
-
-        if pos >= len {
-            return Default::default();
-        }
-
-        &(self.get_ref().as_ref())[pos..]
+        self
     }
 
+    #[inline]
     fn advance(&mut self, cnt: usize) {
-        let pos = (self.position() as usize)
-            .checked_add(cnt).expect("overflow");
-
-        assert!(pos <= self.get_ref().as_ref().len());
-
-        self.set_position(pos as u64);
+        *self = &self[cnt..];
     }
 }
 

src/buf/buf_mut.rs

@@ -2,7 +2,7 @@ use super::{IntoBuf, Writer};
 use byteorder::{LittleEndian, ByteOrder, BigEndian};
 use iovec::IoVecMut;
 
-use std::{cmp, io, ptr, usize};
+use std::{cmp, ptr, usize};
 
 /// A trait for values that provide sequential write access to bytes.
 ///
@@ -34,10 +34,10 @@ pub trait BufMut {
     /// # Examples
     ///
     /// ```
-    /// use bytes::{BufMut, BytesMut};
+    /// use bytes::BufMut;
     ///
-    /// let mut src = [0u8; 10];
-    /// let mut buf = BytesMut::from(&src[..]);
+    /// let mut dst = [0; 10];
+    /// let mut buf = &mut dst[..];
     ///
     /// let original_remaining = buf.remaining_mut();
     /// buf.put("hello");
@@ -104,10 +104,9 @@ pub trait BufMut {
     ///
     /// ```
     /// use bytes::BufMut;
-    /// use std::io::Cursor;
     ///
     /// let mut dst = [0; 5];
-    /// let mut buf = Cursor::new(&mut dst);
+    /// let mut buf = &mut dst[..];
     ///
     /// assert!(buf.has_remaining_mut());
     ///
@@ -254,12 +253,11 @@ pub trait BufMut {
     ///
     /// ```
     /// use bytes::BufMut;
-    /// use std::io::Cursor;
     ///
     /// let mut dst = [0; 6];
     ///
     /// {
-    ///     let mut buf = Cursor::new(&mut dst);
+    ///     let mut buf = &mut dst[..];
     ///     buf.put_slice(b"hello");
     ///
     ///     assert_eq!(1, buf.remaining_mut());
@@ -1018,31 +1016,22 @@ impl<T: BufMut + ?Sized> BufMut for Box<T> {
     }
 }
 
-impl<T: AsMut<[u8]> + AsRef<[u8]>> BufMut for io::Cursor<T> {
+impl<'a> BufMut for &'a mut [u8] {
+    #[inline]
     fn remaining_mut(&self) -> usize {
-        use Buf;
-        self.remaining()
+        self.len()
     }
 
-    /// Advance the internal cursor of the BufMut
-    unsafe fn advance_mut(&mut self, cnt: usize) {
-        use Buf;
-        self.advance(cnt);
-    }
-
-    /// Returns a mutable slice starting at the current BufMut position and of
-    /// length between 0 and `BufMut::remaining()`.
-    ///
-    /// The returned byte slice may represent uninitialized memory.
+    #[inline]
     unsafe fn bytes_mut(&mut self) -> &mut [u8] {
-        let len = self.get_ref().as_ref().len();
-        let pos = self.position() as usize;
+        self
+    }
 
-        if pos >= len {
-            return Default::default();
-        }
-
-        &mut (self.get_mut().as_mut())[pos..]
+    #[inline]
+    unsafe fn advance_mut(&mut self, cnt: usize) {
+        // Lifetime dance taken from `impl Write for &mut [u8]`.
+        let (_, b) = ::std::mem::replace(self, &mut []).split_at_mut(cnt);
+        *self = b;
     }
 }
 

src/buf/into_buf.rs

@@ -1,6 +1,5 @@
 use super::{Buf};
-
-use std::io;
+use ::BytesMut;
 
 /// Conversion into a `Buf`
 ///
@@ -55,58 +54,42 @@ impl<T: Buf> IntoBuf for T {
     }
 }
 
-impl<'a> IntoBuf for &'a [u8] {
-    type Buf = io::Cursor<&'a [u8]>;
-
-    fn into_buf(self) -> Self::Buf {
-        io::Cursor::new(self)
-    }
-}
-
-impl<'a> IntoBuf for &'a mut [u8] {
-    type Buf = io::Cursor<&'a mut [u8]>;
-
-    fn into_buf(self) -> Self::Buf {
-        io::Cursor::new(self)
-    }
-}
-
 impl<'a> IntoBuf for &'a str {
-    type Buf = io::Cursor<&'a [u8]>;
+    type Buf = &'a [u8];
 
     fn into_buf(self) -> Self::Buf {
-        self.as_bytes().into_buf()
+        self.as_bytes()
     }
 }
 
 impl IntoBuf for Vec<u8> {
-    type Buf = io::Cursor<Vec<u8>>;
+    type Buf = BytesMut;
 
     fn into_buf(self) -> Self::Buf {
-        io::Cursor::new(self)
+        self.into()
     }
 }
 
 impl<'a> IntoBuf for &'a Vec<u8> {
-    type Buf = io::Cursor<&'a [u8]>;
+    type Buf = &'a [u8];
 
     fn into_buf(self) -> Self::Buf {
-        io::Cursor::new(&self[..])
+        self.as_slice()
     }
 }
 
 // Kind of annoying... but this impl is required to allow passing `&'static
 // [u8]` where for<'a> &'a T: IntoBuf is required.
 impl<'a> IntoBuf for &'a &'static [u8] {
-    type Buf = io::Cursor<&'static [u8]>;
+    type Buf = &'static [u8];
 
     fn into_buf(self) -> Self::Buf {
-        io::Cursor::new(self)
+        *self
     }
 }
 
 impl<'a> IntoBuf for &'a &'static str {
-    type Buf = io::Cursor<&'static [u8]>;
+    type Buf = &'static [u8];
 
     fn into_buf(self) -> Self::Buf {
         self.as_bytes().into_buf()
@@ -114,7 +97,7 @@ impl<'a> IntoBuf for &'a &'static str {
 }
 
 impl IntoBuf for String {
-    type Buf = io::Cursor<Vec<u8>>;
+    type Buf = BytesMut;
 
     fn into_buf(self) -> Self::Buf {
         self.into_bytes().into_buf()
@@ -122,7 +105,7 @@ impl IntoBuf for String {
 }
 
 impl<'a> IntoBuf for &'a String {
-    type Buf = io::Cursor<&'a [u8]>;
+    type Buf = &'a [u8];
 
     fn into_buf(self) -> Self::Buf {
         self.as_bytes().into_buf()

src/buf/reader.rs

@@ -25,11 +25,10 @@ impl<B: Buf> Reader<B> {
     ///
     /// ```rust
     /// use bytes::Buf;
-    /// use std::io::{self, Cursor};
     ///
-    /// let mut buf = Cursor::new(b"hello world").reader();
+    /// let mut buf = b"hello world".reader();
     ///
-    /// assert_eq!(0, buf.get_ref().position());
+    /// assert_eq!(b"hello world", buf.get_ref());
     /// ```
     pub fn get_ref(&self) -> &B {
         &self.buf
@@ -38,21 +37,6 @@ impl<B: Buf> Reader<B> {
     /// Gets a mutable reference to the underlying `Buf`.
     ///
     /// It is inadvisable to directly read from the underlying `Buf`.
-    ///
-    /// # Examples
-    ///
-    /// ```rust
-    /// use bytes::Buf;
-    /// use std::io::{self, Cursor};
-    ///
-    /// let mut buf = Cursor::new(b"hello world").reader();
-    /// let mut dst = vec![];
-    ///
-    /// buf.get_mut().set_position(2);
-    /// io::copy(&mut buf, &mut dst).unwrap();
-    ///
-    /// assert_eq!(*dst, b"llo world"[..]);
-    /// ```
     pub fn get_mut(&mut self) -> &mut B {
         &mut self.buf
     }
@@ -63,9 +47,9 @@ impl<B: Buf> Reader<B> {
     ///
     /// ```rust
     /// use bytes::Buf;
-    /// use std::io::{self, Cursor};
+    /// use std::io;
     ///
-    /// let mut buf = Cursor::new(b"hello world").reader();
+    /// let mut buf = b"hello world".reader();
     /// let mut dst = vec![];
     ///
     /// io::copy(&mut buf, &mut dst).unwrap();

src/buf/take.rs

@@ -25,9 +25,9 @@ impl<T> Take<T> {
     /// # Examples
     ///
     /// ```rust
-    /// use bytes::{Buf, BufMut, Bytes};
+    /// use bytes::{Buf, BufMut};
     ///
-    /// let mut buf = Bytes::from_static(b"hello world").take(2);
+    /// let mut buf = b"hello world".take(2);
     /// let mut dst = vec![];
     ///
     /// dst.put(&mut buf);
@@ -50,9 +50,9 @@ impl<T> Take<T> {
     /// # Examples
     ///
     /// ```rust
-    /// use bytes::{Buf, BufMut, Bytes};
+    /// use bytes::{Buf, BufMut};
     ///
-    /// let mut buf = Bytes::from_static(b"hello world").take(2);
+    /// let mut buf = b"hello world".take(2);
     ///
     /// assert_eq!(11, buf.get_ref().remaining());
     /// ```
@@ -67,9 +67,9 @@ impl<T> Take<T> {
     /// # Examples
     ///
     /// ```rust
-    /// use bytes::{Buf, BufMut, Bytes};
+    /// use bytes::{Buf, BufMut};
     ///
-    /// let mut buf = Bytes::from_static(b"hello world").take(2);
+    /// let mut buf = b"hello world".take(2);
     /// let mut dst = vec![];
     ///
     /// buf.get_mut().advance(2);
@@ -91,9 +91,9 @@ impl<T> Take<T> {
     /// # Examples
     ///
     /// ```rust
-    /// use bytes::{Buf, Bytes};
+    /// use bytes::Buf;
     ///
-    /// let mut buf = Bytes::from_static(b"hello world").take(2);
+    /// let mut buf = b"hello world".take(2);
     ///
     /// assert_eq!(2, buf.limit());
     /// assert_eq!(b'h', buf.get_u8());
@@ -113,9 +113,9 @@ impl<T> Take<T> {
     /// # Examples
     ///
     /// ```rust
-    /// use bytes::{Buf, BufMut, Bytes};
+    /// use bytes::{Buf, BufMut};
     ///
-    /// let mut buf = Bytes::from_static(b"hello world").take(2);
+    /// let mut buf = b"hello world".take(2);
     /// let mut dst = vec![];
     ///
     /// dst.put(&mut buf);

src/buf/writer.rs

@@ -59,10 +59,10 @@ impl<B: BufMut> Writer<B> {
     ///
     /// ```rust
     /// use bytes::BufMut;
-    /// use std::io::{self, Cursor};
+    /// use std::io;
     ///
     /// let mut buf = vec![].writer();
-    /// let mut src = Cursor::new(b"hello world");
+    /// let mut src = &b"hello world"[..];
     ///
     /// io::copy(&mut src, &mut buf).unwrap();
     ///

src/bytes.rs

@@ -1,4 +1,4 @@
-use {Buf, BufMut};
+use {Buf, BufMut, IntoBuf};
 use buf::IntoIter;
 use debug;
 
@@ -1058,12 +1058,12 @@ impl IntoIterator for Bytes {
     }
 }
 
-impl<'a> IntoIterator for &'a mut Bytes {
-    type Item = u8;
-    type IntoIter = IntoIter<&'a mut Bytes>;
+impl<'a> IntoIterator for &'a Bytes {
+    type Item = &'a u8;
+    type IntoIter = ::std::slice::Iter<'a, u8>;
 
     fn into_iter(self) -> Self::IntoIter {
-        IntoIter::new(self)
+        self.as_ref().into_iter()
     }
 }
 
@@ -1636,6 +1636,14 @@ impl BufMut for BytesMut {
     }
 }
 
+impl<'a> IntoBuf for &'a BytesMut {
+    type Buf = &'a [u8];
+
+    fn into_buf(self) -> Self::Buf {
+        self.as_ref()
+    }
+}
+
 impl AsRef<[u8]> for BytesMut {
     #[inline]
     fn as_ref(&self) -> &[u8] {
@@ -1807,12 +1815,12 @@ impl IntoIterator for BytesMut {
     }
 }
 
-impl<'a> IntoIterator for &'a mut BytesMut {
-    type Item = u8;
-    type IntoIter = IntoIter<&'a mut BytesMut>;
+impl<'a> IntoIterator for &'a BytesMut {
+    type Item = &'a u8;
+    type IntoIter = ::std::slice::Iter<'a, u8>;
 
     fn into_iter(self) -> Self::IntoIter {
-        IntoIter::new(self)
+        self.as_ref().into_iter()
     }
 }
 

tests/test_buf.rs

@@ -4,11 +4,10 @@ extern crate iovec;
 
 use bytes::Buf;
 use iovec::IoVec;
-use std::io::Cursor;
 
 #[test]
 fn test_fresh_cursor_vec() {
-    let mut buf = Cursor::new(b"hello".to_vec());
+    let mut buf = &b"hello"[..];
 
     assert_eq!(buf.remaining(), 5);
     assert_eq!(buf.bytes(), b"hello");
@@ -26,27 +25,28 @@ fn test_fresh_cursor_vec() {
 
 #[test]
 fn test_get_u8() {
-    let mut buf = Cursor::new(b"\x21zomg");
+    let mut buf = &b"\x21zomg"[..];
     assert_eq!(0x21, buf.get_u8());
 }
 
 #[test]
 fn test_get_u16() {
-    let buf = b"\x21\x54zomg";
-    assert_eq!(0x2154, Cursor::new(buf).get_u16());
-    assert_eq!(0x5421, Cursor::new(buf).get_u16_le());
+    let mut buf = &b"\x21\x54zomg"[..];
+    assert_eq!(0x2154, buf.get_u16());
+    let mut buf = &b"\x21\x54zomg"[..];
+    assert_eq!(0x5421, buf.get_u16_le());
 }
 
 #[test]
 #[should_panic]
 fn test_get_u16_buffer_underflow() {
-    let mut buf = Cursor::new(b"\x21");
+    let mut buf = &b"\x21"[..];
     buf.get_u16();
 }
 
 #[test]
 fn test_bufs_vec() {
-    let buf = Cursor::new(b"hello world");
+    let buf = &b"hello world"[..];
 
     let b1: &[u8] = &mut [0];
     let b2: &[u8] = &mut [0];

tests/test_buf_mut.rs

@@ -81,3 +81,10 @@ fn test_bufs_vec_mut() {
         assert_eq!(1, buf.bytes_vec_mut(&mut dst[..]));
     }
 }
+
+#[test]
+fn test_mut_slice() {
+    let mut v = vec![0, 0, 0, 0];
+    let mut s = &mut v[..];
+    s.put_u32(42);
+}

tests/test_bytes.rs

@@ -1,6 +1,6 @@
 extern crate bytes;
 
-use bytes::{Bytes, BytesMut, Buf, BufMut, IntoBuf};
+use bytes::{Bytes, BytesMut, Buf, BufMut};
 
 const LONG: &'static [u8] = b"mary had a little lamb, little lamb, little lamb";
 const SHORT: &'static [u8] = b"hello world";
@@ -181,11 +181,11 @@ fn split_off_to_loop() {
         }
         {
             let mut bytes = BytesMut::from(&s[..]);
-            let mut off = bytes.split_off(i);
+            let off = bytes.split_off(i);
             assert_eq!(i, bytes.len());
             let mut sum = Vec::new();
-            sum.extend(&mut bytes);
-            sum.extend(&mut off);
+            sum.extend(&bytes);
+            sum.extend(&off);
             assert_eq!(&s[..], &sum[..]);
         }
         {
@@ -199,11 +199,11 @@ fn split_off_to_loop() {
         }
         {
             let mut bytes = BytesMut::from(&s[..]);
-            let mut off = bytes.split_to(i);
+            let off = bytes.split_to(i);
             assert_eq!(i, off.len());
             let mut sum = Vec::new();
-            sum.extend(&mut off);
-            sum.extend(&mut bytes);
+            sum.extend(&off);
+            sum.extend(&bytes);
             assert_eq!(&s[..], &sum[..]);
         }
     }
@@ -294,17 +294,10 @@ fn fns_defined_for_bytes_mut() {
     bytes.as_mut_ptr();
 
     // Iterator
-    let v: Vec<u8> = bytes.iter().map(|b| *b).collect();
+    let v: Vec<u8> = bytes.as_ref().iter().cloned().collect();
     assert_eq!(&v[..], bytes);
 }
 
-#[test]
-fn mut_into_buf() {
-    let mut v = vec![0, 0, 0, 0];
-    let s = &mut v[..];
-    s.into_buf().put_u32_le(42);
-}
-
 #[test]
 fn reserve_convert() {
     // Inline -> Vec

tests/test_chain.rs

@@ -4,12 +4,11 @@ extern crate iovec;
 use bytes::{Buf, BufMut, Bytes, BytesMut};
 use bytes::buf::Chain;
 use iovec::IoVec;
-use std::io::Cursor;
 
 #[test]
 fn collect_two_bufs() {
-    let a = Cursor::new(Bytes::from(&b"hello"[..]));
-    let b = Cursor::new(Bytes::from(&b"world"[..]));
+    let a = Bytes::from(&b"hello"[..]);
+    let b = Bytes::from(&b"world"[..]);
 
     let res: Vec<u8> = a.chain(b).collect();
     assert_eq!(res, &b"helloworld"[..]);
@@ -49,8 +48,8 @@ fn iterating_two_bufs() {
 
 #[test]
 fn vectored_read() {
-    let a = Cursor::new(Bytes::from(&b"hello"[..]));
-    let b = Cursor::new(Bytes::from(&b"world"[..]));
+    let a = Bytes::from(&b"hello"[..]);
+    let b = Bytes::from(&b"world"[..]);
 
     let mut buf = a.chain(b);
 

tests/test_from_buf.rs

@@ -1,34 +1,33 @@
 extern crate bytes;
 
 use bytes::{Buf, Bytes, BytesMut};
-use std::io::Cursor;
 
 const LONG: &'static [u8] = b"mary had a little lamb, little lamb, little lamb";
 const SHORT: &'static [u8] = b"hello world";
 
 #[test]
 fn collect_to_vec() {
-    let buf: Vec<u8> = Cursor::new(SHORT).collect();
+    let buf: Vec<u8> = SHORT.collect();
     assert_eq!(buf, SHORT);
 
-    let buf: Vec<u8> = Cursor::new(LONG).collect();
+    let buf: Vec<u8> = LONG.collect();
     assert_eq!(buf, LONG);
 }
 
 #[test]
 fn collect_to_bytes() {
-    let buf: Bytes = Cursor::new(SHORT).collect();
+    let buf: Bytes = SHORT.collect();
     assert_eq!(buf, SHORT);
 
-    let buf: Bytes = Cursor::new(LONG).collect();
+    let buf: Bytes = LONG.collect();
     assert_eq!(buf, LONG);
 }
 
 #[test]
 fn collect_to_bytes_mut() {
-    let buf: BytesMut = Cursor::new(SHORT).collect();
+    let buf: BytesMut = SHORT.collect();
     assert_eq!(buf, SHORT);
 
-    let buf: BytesMut = Cursor::new(LONG).collect();
+    let buf: BytesMut = LONG.collect();
     assert_eq!(buf, LONG);
 }

tests/test_reader.rs

@@ -1,13 +1,13 @@
 extern crate bytes;
 
-use std::io::{BufRead, Cursor, Read};
+use std::io::{BufRead, Read};
 
 use bytes::Buf;
 
 #[test]
 fn read() {
-    let buf1 = Cursor::new(b"hello ");
-    let buf2 = Cursor::new(b"world");
+    let buf1 = &b"hello "[..];
+    let buf2 = &b"world"[..];
     let buf = Buf::chain(buf1, buf2); // Disambiguate with Read::chain
     let mut buffer = Vec::new();
     buf.reader().read_to_end(&mut buffer).unwrap();
@@ -16,8 +16,8 @@ fn read() {
 
 #[test]
 fn buf_read() {
-    let buf1 = Cursor::new(b"hell");
-    let buf2 = Cursor::new(b"o\nworld");
+    let buf1 = &b"hell"[..];
+    let buf2 = &b"o\nworld"[..];
     let mut reader = Buf::chain(buf1, buf2).reader();
     let mut line = String::new();
     reader.read_line(&mut line).unwrap();

tests/test_take.rs

@@ -1,13 +1,12 @@
 extern crate bytes;
 
 use bytes::Buf;
-use std::io::Cursor;
 
 #[test]
 fn long_take() {
     // Tests that get a take with a size greater than the buffer length will not
     // overrun the buffer. Regression test for #138.
-    let buf = Cursor::new(b"hello world").take(100);
+    let buf = b"hello world".take(100);
     assert_eq!(11, buf.remaining());
     assert_eq!(b"hello world", buf.bytes());
 }