refactor(error): remove redundant parts of error names

The old names followed the old style of including the module name and
"Error" in each variant. The new style is to refer to an error from its
owning module, and variants are now scoped to their enum, so there's no
need to include the enum name in the variant name.

BREAKING CHANGE: The terms `Http` and `Error` have been removed from the Error
  type and its variants. `HttpError` should now be accessed as `hyper::Error`,
  and variants like `HttpIoError` should be accessed as `Error::Io`.

src/http.rs

@@ -13,8 +13,7 @@ use method::Method;
 use status::StatusCode;
 use uri::RequestUri;
 use version::HttpVersion::{self, Http10, Http11};
-use HttpError::{HttpIoError, HttpTooLargeError};
-use {HttpError, HttpResult};
+use {Error};
 
 use self::HttpReader::{SizedReader, ChunkedReader, EofReader, EmptyReader};
 use self::HttpWriter::{ThroughWriter, ChunkedWriter, SizedWriter, EmptyWriter};
@@ -334,17 +333,17 @@ const MAX_HEADERS: usize = 100;
 
 /// Parses a request into an Incoming message head.
 #[inline]
-pub fn parse_request<R: Read>(buf: &mut BufReader<R>) -> HttpResult<Incoming<(Method, RequestUri)>> {
+pub fn parse_request<R: Read>(buf: &mut BufReader<R>) -> ::Result<Incoming<(Method, RequestUri)>> {
     parse::<R, httparse::Request, (Method, RequestUri)>(buf)
 }
 
 /// Parses a response into an Incoming message head.
 #[inline]
-pub fn parse_response<R: Read>(buf: &mut BufReader<R>) -> HttpResult<Incoming<RawStatus>> {
+pub fn parse_response<R: Read>(buf: &mut BufReader<R>) -> ::Result<Incoming<RawStatus>> {
     parse::<R, httparse::Response, RawStatus>(buf)
 }
 
-fn parse<R: Read, T: TryParse<Subject=I>, I>(rdr: &mut BufReader<R>) -> HttpResult<Incoming<I>> {
+fn parse<R: Read, T: TryParse<Subject=I>, I>(rdr: &mut BufReader<R>) -> ::Result<Incoming<I>> {
     loop {
         match try!(try_parse::<R, T, I>(rdr)) {
             httparse::Status::Complete((inc, len)) => {
@@ -355,12 +354,12 @@ fn parse<R: Read, T: TryParse<Subject=I>, I>(rdr: &mut BufReader<R>) -> HttpResu
         }
         match try!(rdr.read_into_buf()) {
             0 if rdr.get_buf().is_empty() => {
-                return Err(HttpIoError(io::Error::new(
+                return Err(Error::Io(io::Error::new(
                     io::ErrorKind::ConnectionAborted,
                     "Connection closed"
                 )))
             },
-            0 => return Err(HttpTooLargeError),
+            0 => return Err(Error::TooLarge),
             _ => ()
         }
     }
@@ -377,7 +376,7 @@ trait TryParse {
     fn try_parse<'a>(headers: &'a mut [httparse::Header<'a>], buf: &'a [u8]) -> TryParseResult<Self::Subject>;
 }
 
-type TryParseResult<T> = Result<httparse::Status<(Incoming<T>, usize)>, HttpError>;
+type TryParseResult<T> = Result<httparse::Status<(Incoming<T>, usize)>, Error>;
 
 impl<'a> TryParse for httparse::Request<'a, 'a> {
     type Subject = (Method, RequestUri);
@@ -552,12 +551,12 @@ mod tests {
     #[test]
     fn test_parse_tcp_closed() {
         use std::io::ErrorKind;
-        use error::HttpError::HttpIoError;
+        use error::Error;
 
         let mut empty = MockStream::new();
         let mut buf = BufReader::new(&mut empty);
         match parse_request(&mut buf) {
-            Err(HttpIoError(ref e)) if e.kind() == ErrorKind::ConnectionAborted => (),
+            Err(Error::Io(ref e)) if e.kind() == ErrorKind::ConnectionAborted => (),
             other => panic!("unexpected result: {:?}", other)
         }
     }