Replace ByteString::as_slice() by a Deref implementation.

components/script/dom/bindings/conversions.rs

@@ -400,9 +400,8 @@ impl FromJSValConvertible for USVString {
 impl ToJSValConvertible for ByteString {
     fn to_jsval(&self, cx: *mut JSContext) -> JSVal {
         unsafe {
-            let slice = self.as_slice();
+            let jsstr = JS_NewStringCopyN(cx, self.as_ptr() as *const libc::c_char,
-            let jsstr = JS_NewStringCopyN(cx, slice.as_ptr() as *const libc::c_char,
+                                          self.len() as libc::size_t);
-                                          slice.len() as libc::size_t);
             if jsstr.is_null() {
                 panic!("JS_NewStringCopyN failed");
             }

components/script/dom/bindings/str.rs

@@ -6,6 +6,7 @@
 
 use std::borrow::ToOwned;
 use std::hash::{Hash, Hasher};
+use std::ops;
 use std::str;
 use std::str::FromStr;
 
@@ -27,12 +28,6 @@ impl ByteString {
         str::from_utf8(&vec).ok()
     }
 
-    /// Returns the underlying vector as a slice.
-    pub fn as_slice<'a>(&'a self) -> &'a [u8] {
-        let ByteString(ref vector) = *self;
-        vector
-    }
-
     /// Returns the length.
     pub fn len(&self) -> usize {
         let ByteString(ref vector) = *self;
@@ -158,6 +153,13 @@ impl FromStr for ByteString {
     }
 }
 
+impl ops::Deref for ByteString {
+    type Target = [u8];
+    fn deref(&self) -> &[u8] {
+        &self.0
+    }
+}
+
 /// A string that is constructed from a UCS-2 buffer by replacing invalid code
 /// points with the replacement character.
 pub struct USVString(pub String);

components/script/dom/xmlhttprequest.rs

@@ -399,14 +399,14 @@ impl<'a> XMLHttpRequestMethods for JSRef<'a, XMLHttpRequest> {
                 debug!("SetRequestHeader: old value = {:?}", raw[0]);
                 let mut buf = raw[0].clone();
                 buf.push_all(b", ");
-                buf.push_all(value.as_slice());
+                buf.push_all(&value);
                 debug!("SetRequestHeader: new value = {:?}", buf);
                 value = ByteString::new(buf);
             },
             None => {}
         }
 
-        headers.set_raw(name_str.to_owned(), vec![value.as_slice().to_vec()]);
+        headers.set_raw(name_str.to_owned(), vec![value.to_vec()]);
         Ok(())
     }
 
@@ -678,7 +678,7 @@ impl<'a> XMLHttpRequestMethods for JSRef<'a, XMLHttpRequest> {
             },
             _ if self.ready_state.get() != XMLHttpRequestState::Done => NullValue(),
             Json => {
-                let decoded = UTF_8.decode(self.response.borrow().as_slice(), DecoderTrap::Replace).unwrap().to_owned();
+                let decoded = UTF_8.decode(&self.response.borrow(), DecoderTrap::Replace).unwrap().to_owned();
                 let decoded: Vec<u16> = decoded.utf16_units().collect();
                 let mut vp = UndefinedValue();
                 unsafe {
@@ -1028,7 +1028,7 @@ impl<'a> PrivateXMLHttpRequestHelpers for JSRef<'a, XMLHttpRequest> {
         let response = self.response.borrow();
         // According to Simon, decode() should never return an error, so unwrap()ing
         // the result should be fine. XXXManishearth have a closer look at this later
-        encoding.decode(response.as_slice(), DecoderTrap::Replace).unwrap().to_owned()
+        encoding.decode(&response, DecoderTrap::Replace).unwrap().to_owned()
     }
     fn filter_response_headers(self) -> Headers {
         // https://fetch.spec.whatwg.org/#concept-response-header-list