Auto merge of #23934 - lfairy:write-no-deref, r=alexcrichton

[rust.git] / src / libstd / io / util.rs

diff --git a/src/libstd/io/util.rs b/src/libstd/io/util.rs
index 3d342137c62ddd3d3a340811384d1dc2e166efd8..c82f9515e8d52813ba494a6b0a48b0b71bc27a65 100644 (file)
--- a/src/libstd/io/util.rs
+++ b/src/libstd/io/util.rs
@@ -12,7 +12,7 @@
 
 use prelude::v1::*;
 
-use io::{self, Read, Write, ErrorKind};
+use io::{self, Read, Write, ErrorKind, BufRead};
 
 /// Copies the entire contents of a reader into a writer.
 ///
@@ -27,6 +27,7 @@
 /// This function will return an error immediately if any call to `read` or
 /// `write` returns an error. All instances of `ErrorKind::Interrupted` are
 /// handled by this function and the underlying operation is retried.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub fn copy<R: Read, W: Write>(r: &mut R, w: &mut W) -> io::Result<u64> {
     let mut buf = [0; super::DEFAULT_BUF_SIZE];
     let mut written = 0;
@@ -43,26 +44,37 @@ pub fn copy<R: Read, W: Write>(r: &mut R, w: &mut W) -> io::Result<u64> {
 }
 
 /// A reader which is always at EOF.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub struct Empty { _priv: () }
 
 /// Creates an instance of an empty reader.
 ///
 /// All reads from the returned reader will return `Ok(0)`.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub fn empty() -> Empty { Empty { _priv: () } }
 
+#[stable(feature = "rust1", since = "1.0.0")]
 impl Read for Empty {
     fn read(&mut self, _buf: &mut [u8]) -> io::Result<usize> { Ok(0) }
 }
+#[stable(feature = "rust1", since = "1.0.0")]
+impl BufRead for Empty {
+    fn fill_buf(&mut self) -> io::Result<&[u8]> { Ok(&[]) }
+    fn consume(&mut self, _n: usize) {}
+}
 
 /// A reader which infinitely yields one byte.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub struct Repeat { byte: u8 }
 
 /// Creates an instance of a reader that infinitely repeats one byte.
 ///
 /// All reads from this reader will succeed by filling the specified buffer with
 /// the given byte.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub fn repeat(byte: u8) -> Repeat { Repeat { byte: byte } }
 
+#[stable(feature = "rust1", since = "1.0.0")]
 impl Read for Repeat {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         for slot in buf.iter_mut() {
@@ -73,14 +85,17 @@ fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
 }
 
 /// A writer which will move data into the void.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub struct Sink { _priv: () }
 
 /// Creates an instance of a writer which will successfully consume all data.
 ///
 /// All calls to `write` on the returned instance will return `Ok(buf.len())`
 /// and the contents of the buffer will not be inspected.
+#[stable(feature = "rust1", since = "1.0.0")]
 pub fn sink() -> Sink { Sink { _priv: () } }
 
+#[stable(feature = "rust1", since = "1.0.0")]
 impl Write for Sink {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> { Ok(buf.len()) }
     fn flush(&mut self) -> io::Result<()> { Ok(()) }
@@ -96,33 +111,33 @@ mod test {
     #[test]
     fn sink_sinks() {
         let mut s = sink();
-        assert_eq!(s.write(&[]), Ok(0));
-        assert_eq!(s.write(&[0]), Ok(1));
-        assert_eq!(s.write(&[0; 1024]), Ok(1024));
-        assert_eq!(s.by_ref().write(&[0; 1024]), Ok(1024));
+        assert_eq!(s.write(&[]).unwrap(), 0);
+        assert_eq!(s.write(&[0]).unwrap(), 1);
+        assert_eq!(s.write(&[0; 1024]).unwrap(), 1024);
+        assert_eq!(s.by_ref().write(&[0; 1024]).unwrap(), 1024);
     }
 
     #[test]
     fn empty_reads() {
         let mut e = empty();
-        assert_eq!(e.read(&mut []), Ok(0));
-        assert_eq!(e.read(&mut [0]), Ok(0));
-        assert_eq!(e.read(&mut [0; 1024]), Ok(0));
-        assert_eq!(e.by_ref().read(&mut [0; 1024]), Ok(0));
+        assert_eq!(e.read(&mut []).unwrap(), 0);
+        assert_eq!(e.read(&mut [0]).unwrap(), 0);
+        assert_eq!(e.read(&mut [0; 1024]).unwrap(), 0);
+        assert_eq!(e.by_ref().read(&mut [0; 1024]).unwrap(), 0);
     }
 
     #[test]
     fn repeat_repeats() {
         let mut r = repeat(4);
         let mut b = [0; 1024];
-        assert_eq!(r.read(&mut b), Ok(1024));
+        assert_eq!(r.read(&mut b).unwrap(), 1024);
         assert!(b.iter().all(|b| *b == 4));
     }
 
     #[test]
     fn take_some_bytes() {
         assert_eq!(repeat(4).take(100).bytes().count(), 100);
-        assert_eq!(repeat(4).take(100).bytes().next(), Some(Ok(4)));
+        assert_eq!(repeat(4).take(100).bytes().next().unwrap().unwrap(), 4);
         assert_eq!(repeat(1).take(10).chain(repeat(2).take(10)).bytes().count(), 20);
     }
 
@@ -131,7 +146,7 @@ fn tee() {
         let mut buf = [0; 10];
         {
             let mut ptr: &mut [u8] = &mut buf;
-            assert_eq!(repeat(4).tee(&mut ptr).take(5).read(&mut [0; 10]), Ok(5));
+            assert_eq!(repeat(4).tee(&mut ptr).take(5).read(&mut [0; 10]).unwrap(), 5);
         }
         assert_eq!(buf, [4, 4, 4, 4, 4, 0, 0, 0, 0, 0]);
     }
@@ -145,7 +160,7 @@ fn broadcast() {
             let mut ptr2: &mut [u8] = &mut buf2;
 
             assert_eq!((&mut ptr1).broadcast(&mut ptr2)
-                                  .write(&[1, 2, 3]), Ok(3));
+                                  .write(&[1, 2, 3]).unwrap(), 3);
         }
         assert_eq!(buf1, buf2);
         assert_eq!(buf1, [1, 2, 3, 0, 0, 0, 0, 0, 0, 0]);