remove Buffer's Read implementation

The previous implementation was incorrect because it essentially
recreated a slice of the Buffer on each call, meaning that read progress
information was lost across calls.

The implementation has been removed since the implementation was very
basic anyways.

Going forward, one can Read from a Buffer by first getting a slice of
the Buffer and then using _its_ Read implementation. See the regression
test in this commit for an example of using read_to_end().

Fixes #6

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "hoedown"
-version = "5.0.0"
+version = "6.0.0"
 authors = ["Jorge Israel Peña <[email protected]>"]
 description = "bindings for the Hoedown markdown processor"
 repository = "https://github.com/blaenk/hoedown"
@@ -14,6 +14,7 @@ libc = "0.2"
 
 [dev-dependencies]
 glob = "0.2"
+timebomb = "0.1.2"
 
 [build-dependencies]
 gcc = "0.3"

src/buffer.rs

@@ -128,13 +128,6 @@ impl Clone for Buffer {
     }
 }
 
-impl Read for Buffer {
-    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        let mut buffer: &[u8] = self.as_ref();
-        Read::read(&mut buffer, buf)
-    }
-}
-
 impl Write for Buffer {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         unsafe {

tests/buffer.rs

@@ -0,0 +1,21 @@
+extern crate hoedown;
+extern crate timebomb;
+
+use std::vec::Vec;
+use std::io::Read;
+
+use hoedown::Buffer;
+
+use timebomb::timeout_ms;
+
+#[test]
+fn test_read_to_end() {
+    let buffer = Buffer::from("This is a test");
+    let mut destination = Vec::new();
+
+    timeout_ms(move || {
+        let mut slice: &[u8] = &buffer;
+
+        slice.read_to_end(&mut destination).unwrap();
+    }, 1000);
+}