fix(client): GET and HEAD shouldn't add Transfer-Encoding

Also adds an EmptyWriter, used for GET and HEAD requests,
which will return an io::ShortWrite error if the user ever tries
to write to a GET or HEAD request.

Closes #77

src/client/request.rs

@@ -7,7 +7,7 @@ use method::{mod, Get, Post, Delete, Put, Patch, Head, Options};
 use header::Headers;
 use header::common::{mod, Host};
 use net::{NetworkStream, NetworkConnector, HttpStream, Fresh, Streaming};
-use http::{HttpWriter, ThroughWriter, ChunkedWriter, SizedWriter, LINE_ENDING};
+use http::{HttpWriter, ThroughWriter, ChunkedWriter, SizedWriter, EmptyWriter, LINE_ENDING};
 use version;
 use {HttpResult, HttpUriError};
 use client::Response;
@@ -117,43 +117,50 @@ impl Request<Fresh> {
         try_io!(self.body.write(LINE_ENDING));
 
 
-        let mut chunked = true;
-        let mut len = 0;
-
-        match self.headers.get::<common::ContentLength>() {
-            Some(cl) => {
-                chunked = false;
-                len = cl.len();
+        let stream = match self.method {
+            Get | Head => {
+                EmptyWriter(self.body.unwrap())
             },
-            None => ()
-        };
+            _ => {
+                let mut chunked = true;
+                let mut len = 0;
 
-        // cant do in match above, thanks borrowck
-        if chunked {
-            let encodings = match self.headers.get_mut::<common::TransferEncoding>() {
-                Some(&common::TransferEncoding(ref mut encodings)) => {
-                    //TODO: check if chunked is already in encodings. use HashSet?
-                    encodings.push(common::transfer_encoding::Chunked);
-                    false
-                },
-                None => true
-            };
+                match self.headers.get::<common::ContentLength>() {
+                    Some(cl) => {
+                        chunked = false;
+                        len = cl.len();
+                    },
+                    None => ()
+                };
 
-            if encodings {
-                self.headers.set::<common::TransferEncoding>(
-                    common::TransferEncoding(vec![common::transfer_encoding::Chunked]))
+                // cant do in match above, thanks borrowck
+                if chunked {
+                    let encodings = match self.headers.get_mut::<common::TransferEncoding>() {
+                        Some(&common::TransferEncoding(ref mut encodings)) => {
+                            //TODO: check if chunked is already in encodings. use HashSet?
+                            encodings.push(common::transfer_encoding::Chunked);
+                            false
+                        },
+                        None => true
+                    };
+
+                    if encodings {
+                        self.headers.set::<common::TransferEncoding>(
+                            common::TransferEncoding(vec![common::transfer_encoding::Chunked]))
+                    }
+                }
+
+                debug!("headers [\n{}]", self.headers);
+                try_io!(write!(self.body, "{}", self.headers));
+
+                try_io!(self.body.write(LINE_ENDING));
+
+                if chunked {
+                    ChunkedWriter(self.body.unwrap())
+                } else {
+                    SizedWriter(self.body.unwrap(), len)
+                }
             }
-        }
-
-        debug!("headers [\n{}]", self.headers);
-        try_io!(write!(self.body, "{}", self.headers));
-
-        try_io!(self.body.write(LINE_ENDING));
-
-        let stream = if chunked {
-            ChunkedWriter(self.body.unwrap())
-        } else {
-            SizedWriter(self.body.unwrap(), len)
         };
 
         Ok(Request {
@@ -192,3 +199,38 @@ impl Writer for Request<Streaming> {
     }
 }
 
+#[cfg(test)]
+mod tests {
+    use std::boxed::BoxAny;
+    use std::str::from_utf8;
+    use url::Url;
+    use method::{Get, Head};
+    use mock::MockStream;
+    use super::Request;
+
+    #[test]
+    fn test_get_empty_body() {
+        let req = Request::with_stream::<MockStream>(
+            Get, Url::parse("http://example.dom").unwrap()
+        ).unwrap();
+        let req = req.start().unwrap();
+        let stream = *req.body.end().unwrap().unwrap().downcast::<MockStream>().unwrap();
+        let bytes = stream.write.unwrap();
+        let s = from_utf8(bytes[]).unwrap();
+        assert!(!s.contains("Content-Length:"));
+        assert!(!s.contains("Transfer-Encoding:"));
+    }
+
+    #[test]
+    fn test_head_empty_body() {
+        let req = Request::with_stream::<MockStream>(
+            Head, Url::parse("http://example.dom").unwrap()
+        ).unwrap();
+        let req = req.start().unwrap();
+        let stream = *req.body.end().unwrap().unwrap().downcast::<MockStream>().unwrap();
+        let bytes = stream.write.unwrap();
+        let s = from_utf8(bytes[]).unwrap();
+        assert!(!s.contains("Content-Length:"));
+        assert!(!s.contains("Transfer-Encoding:"));
+    }
+}

src/client/response.rs

@@ -100,11 +100,11 @@ mod tests {
             status: status::Ok,
             headers: Headers::new(),
             version: version::Http11,
-            body: EofReader(BufferedReader::new(box MockStream as Box<NetworkStream + Send>))
+            body: EofReader(BufferedReader::new(box MockStream::new() as Box<NetworkStream + Send>))
         };
 
         let b = res.unwrap().downcast::<MockStream>().unwrap();
-        assert_eq!(b, box MockStream);
+        assert_eq!(b, box MockStream::new());
 
     }
 }

src/http.rs

@@ -157,6 +157,8 @@ pub enum HttpWriter<W: Writer> {
     ///
     /// Enforces that the body is not longer than the Content-Length header.
     SizedWriter(W, uint),
+    /// A writer that should not write any body.
+    EmptyWriter(W),
 }
 
 impl<W: Writer> HttpWriter<W> {
@@ -166,7 +168,8 @@ impl<W: Writer> HttpWriter<W> {
         match self {
             ThroughWriter(w) => w,
             ChunkedWriter(w) => w,
-            SizedWriter(w, _) => w
+            SizedWriter(w, _) => w,
+            EmptyWriter(w) => w,
         }
     }
 
@@ -204,6 +207,18 @@ impl<W: Writer> Writer for HttpWriter<W> {
                     *remaining -= len;
                     w.write(msg)
                 }
+            },
+            EmptyWriter(..) => {
+                let bytes = msg.len();
+                if bytes == 0 {
+                    Ok(())
+                } else {
+                    Err(io::IoError {
+                        kind: io::ShortWrite(bytes),
+                        desc: "EmptyWriter cannot write any bytes",
+                        detail: Some("Cannot include a body with this kind of message".into_string())
+                    })
+                }
             }
         }
     }
@@ -214,6 +229,7 @@ impl<W: Writer> Writer for HttpWriter<W> {
             ThroughWriter(ref mut w) => w.flush(),
             ChunkedWriter(ref mut w) => w.flush(),
             SizedWriter(ref mut w, _) => w.flush(),
+            EmptyWriter(ref mut w) => w.flush(),
         }
     }
 }

src/mock.rs

@@ -1,20 +1,55 @@
-use std::io::IoResult;
+use std::fmt;
+use std::io::{IoResult, MemReader, MemWriter};
 use std::io::net::ip::{SocketAddr, ToSocketAddr};
 
 use net::{NetworkStream, NetworkConnector};
 
-#[deriving(Clone, PartialEq, Show)]
-pub struct MockStream;
+pub struct MockStream {
+    pub read: MemReader,
+    pub write: MemWriter,
+}
 
+impl Clone for MockStream {
+    fn clone(&self) -> MockStream {
+        MockStream {
+            read: MemReader::new(self.read.get_ref().to_vec()),
+            write: MemWriter::from_vec(self.write.get_ref().to_vec()),
+        }
+    }
+}
+
+impl PartialEq for MockStream {
+    fn eq(&self, other: &MockStream) -> bool {
+        self.read.get_ref() == other.read.get_ref() &&
+            self.write.get_ref() == other.write.get_ref()
+    }
+}
+
+impl fmt::Show for MockStream {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "MockStream {{ read: {}, write: {} }}",
+               self.read.get_ref(), self.write.get_ref())
+    }
+
+}
+
+impl MockStream {
+    pub fn new() -> MockStream {
+        MockStream {
+            read: MemReader::new(vec![]),
+            write: MemWriter::new(),
+        }
+    }
+}
 impl Reader for MockStream {
-    fn read(&mut self, _buf: &mut [u8]) -> IoResult<uint> {
-        unimplemented!()
+    fn read(&mut self, buf: &mut [u8]) -> IoResult<uint> {
+        self.read.read(buf)
     }
 }
 
 impl Writer for MockStream {
-    fn write(&mut self, _msg: &[u8]) -> IoResult<()> {
-        unimplemented!()
+    fn write(&mut self, msg: &[u8]) -> IoResult<()> {
+        self.write.write(msg)
     }
 }
 
@@ -27,6 +62,6 @@ impl NetworkStream for MockStream {
 
 impl NetworkConnector for MockStream {
     fn connect<To: ToSocketAddr>(_addr: To, _scheme: &str) -> IoResult<MockStream> {
-        Ok(MockStream)
+        Ok(MockStream::new())
     }
 }

src/net.rs

@@ -274,19 +274,19 @@ mod tests {
 
     #[test]
     fn test_downcast_box_stream() {
-        let stream = box MockStream as Box<NetworkStream + Send>;
+        let stream = box MockStream::new() as Box<NetworkStream + Send>;
 
         let mock = stream.downcast::<MockStream>().unwrap();
-        assert_eq!(mock, box MockStream);
+        assert_eq!(mock, box MockStream::new());
 
     }
 
     #[test]
     fn test_downcast_unchecked_box_stream() {
-        let stream = box MockStream as Box<NetworkStream + Send>;
+        let stream = box MockStream::new() as Box<NetworkStream + Send>;
 
         let mock = unsafe { stream.downcast_unchecked::<MockStream>() };
-        assert_eq!(mock, box MockStream);
+        assert_eq!(mock, box MockStream::new());
 
     }