fix(client): improve HttpReader selection for client Responses

Closes #436

src/header/common/content_length.rs

@@ -1,37 +1,86 @@
-header! {
-    #[doc="`Content-Length` header, defined in"]
-    #[doc="[RFC7230](http://tools.ietf.org/html/rfc7230#section-3.3.2)"]
-    #[doc=""]
-    #[doc="When a message does not have a `Transfer-Encoding` header field, a"]
-    #[doc="Content-Length header field can provide the anticipated size, as a"]
-    #[doc="decimal number of octets, for a potential payload body.  For messages"]
-    #[doc="that do include a payload body, the Content-Length field-value"]
-    #[doc="provides the framing information necessary for determining where the"]
-    #[doc="body (and message) ends.  For messages that do not include a payload"]
-    #[doc="body, the Content-Length indicates the size of the selected"]
-    #[doc="representation."]
-    #[doc=""]
-    #[doc="# ABNF"]
-    #[doc="```plain"]
-    #[doc="Content-Length = 1*DIGIT"]
-    #[doc="```"]
-    #[doc=""]
-    #[doc="# Example values"]
-    #[doc="* `3495`"]
-    #[doc=""]
-    #[doc="# Example"]
-    #[doc="```"]
-    #[doc="use hyper::header::{Headers, ContentLength};"]
-    #[doc=""]
-    #[doc="let mut headers = Headers::new();"]
-    #[doc="headers.set(ContentLength(1024u64));"]
-    #[doc="```"]
-    (ContentLength, "Content-Length") => [u64]
+use std::fmt;
 
-    test_content_length {
-        // Testcase from RFC
-        test_header!(test1, vec![b"3495"], Some(HeaderField(3495)));
+use header::{HeaderFormat, Header, parsing};
+
+#[doc="`Content-Length` header, defined in"]
+#[doc="[RFC7230](http://tools.ietf.org/html/rfc7230#section-3.3.2)"]
+#[doc=""]
+#[doc="When a message does not have a `Transfer-Encoding` header field, a"]
+#[doc="Content-Length header field can provide the anticipated size, as a"]
+#[doc="decimal number of octets, for a potential payload body.  For messages"]
+#[doc="that do include a payload body, the Content-Length field-value"]
+#[doc="provides the framing information necessary for determining where the"]
+#[doc="body (and message) ends.  For messages that do not include a payload"]
+#[doc="body, the Content-Length indicates the size of the selected"]
+#[doc="representation."]
+#[doc=""]
+#[doc="# ABNF"]
+#[doc="```plain"]
+#[doc="Content-Length = 1*DIGIT"]
+#[doc="```"]
+#[doc=""]
+#[doc="# Example values"]
+#[doc="* `3495`"]
+#[doc=""]
+#[doc="# Example"]
+#[doc="```"]
+#[doc="use hyper::header::{Headers, ContentLength};"]
+#[doc=""]
+#[doc="let mut headers = Headers::new();"]
+#[doc="headers.set(ContentLength(1024u64));"]
+#[doc="```"]
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub struct ContentLength(pub u64);
+
+impl Header for ContentLength {
+    #[inline]
+    fn header_name() -> &'static str {
+        "Content-Length"
+    }
+    fn parse_header(raw: &[Vec<u8>]) -> ::Result<ContentLength> {
+        // If multiple Content-Length headers were sent, everything can still
+        // be alright if they all contain the same value, and all parse
+        // correctly. If not, then it's an error.
+        raw.iter()
+            .map(::std::ops::Deref::deref)
+            .map(parsing::from_raw_str)
+            .fold(None, |prev, x| {
+                match (prev, x) {
+                    (None, x) => Some(x),
+                    (e@Some(Err(_)), _ ) => e,
+                    (Some(Ok(prev)), Ok(x)) if prev == x => Some(Ok(prev)),
+                    _ => Some(Err(::Error::Header))
+                }
+            })
+            .unwrap_or(Err(::Error::Header))
+            .map(ContentLength)
     }
 }
 
+impl HeaderFormat for ContentLength {
+    #[inline]
+    fn fmt_header(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Display::fmt(&self.0, f)
+    }
+}
+
+impl fmt::Display for ContentLength {
+    #[inline]
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Display::fmt(&self.0, f)
+    }
+}
+
+__hyper__deref!(ContentLength => u64);
+__hyper_generate_header_serialization!(ContentLength);
+
+__hyper__tm!(ContentLength, tests {
+    // Testcase from RFC
+    test_header!(test1, vec![b"3495"], Some(HeaderField(3495)));
+
+    test_header!(test_invalid, vec![b"34v95"], None);
+    test_header!(test_duplicates, vec![b"5", b"5"], Some(HeaderField(5)));
+    test_header!(test_duplicates_vary, vec![b"5", b"6", b"5"], None);
+});
+
 bench_header!(bench, ContentLength, { vec![b"42349984".to_vec()] });

src/header/common/mod.rs

@@ -148,12 +148,13 @@ macro_rules! test_header {
         fn $id() {
             let a: Vec<Vec<u8>> = $raw.iter().map(|x| x.to_vec()).collect();
             let val = HeaderField::parse_header(&a[..]);
+            let typed: Option<HeaderField> = $typed;
             // Test parsing
-            assert_eq!(val.ok(), $typed);
+            assert_eq!(val.ok(), typed);
             // Test formatting
-            if $typed != None {
+            if typed.is_some() {
                 let res: &str = str::from_utf8($raw[0]).unwrap();
-                assert_eq!(format!("{}", $typed.unwrap()), res);
+                assert_eq!(format!("{}", typed.unwrap()), res);
             }
         }
     }