From ed0ed2a39687f31953ad5af9647143efe7a9528a Mon Sep 17 00:00:00 2001
From: Sergio Benitez <sb@sergio.bz>
Date: Thu, 21 Dec 2017 21:51:36 -0800
Subject: [PATCH] Defer NamedFile's Responder impl to File.

---
 lib/src/response/named_file.rs | 18 ++++++------------
 lib/src/response/responder.rs  |  8 ++++++--
 2 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/lib/src/response/named_file.rs b/lib/src/response/named_file.rs
index b6b08395..04a446e0 100644
--- a/lib/src/response/named_file.rs
+++ b/lib/src/response/named_file.rs
@@ -4,9 +4,8 @@ use std::io;
 use std::ops::{Deref, DerefMut};
 
 use request::Request;
-use response::{Response, Responder};
-use http::{Status, ContentType};
-use response::Body;
+use response::{self, Responder};
+use http::ContentType;
 
 /// A file with an associated name; responds with the Content-Type based on the
 /// file extension.
@@ -80,20 +79,15 @@ impl NamedFile {
 /// [ContentType::from_extension](/rocket/http/struct.ContentType.html#method.from_extension)
 /// for more information. If you would like to stream a file with a different
 /// Content-Type than that implied by its extension, use a `File` directly.
-impl Responder<'static> for NamedFile {
-    fn respond_to(self, _: &Request) -> Result<Response<'static>, Status> {
-        let mut response = Response::new();
-        if let Some(ext) = self.path().extension() {
+impl<'r> Responder<'r> for NamedFile {
+    fn respond_to(self, req: &Request) -> response::Result<'r> {
+        let mut response = self.1.respond_to(req)?;
+        if let Some(ext) = self.0.extension() {
             if let Some(ct) = ContentType::from_extension(&ext.to_string_lossy()) {
                 response.set_header(ct);
             }
         }
 
-        match self.0.metadata() {
-            Ok(meta) => response.set_raw_body(Body::Sized(self.take_file(), meta.len())),
-            Err(_) => response.set_streamed_body(self.take_file())
-        }
-
         Ok(response)
     }
 }
diff --git a/lib/src/response/responder.rs b/lib/src/response/responder.rs
index 362269d7..1a7671e2 100644
--- a/lib/src/response/responder.rs
+++ b/lib/src/response/responder.rs
@@ -3,7 +3,7 @@ use std::io::{Cursor, BufReader};
 use std::fmt;
 
 use http::{Status, ContentType};
-use response::{self, Response};
+use response::{self, Response, Body};
 use request::Request;
 
 /// Trait implemented by types that generate responses for clients.
@@ -223,7 +223,11 @@ impl<'r> Responder<'r> for Vec<u8> {
 /// Returns a response with a sized body for the file. Always returns `Ok`.
 impl<'r> Responder<'r> for File {
     fn respond_to(self, _: &Request) -> response::Result<'r> {
-        Response::build().streamed_body(BufReader::new(self)).ok()
+        let (metadata, file) = (self.metadata(), BufReader::new(self));
+        match metadata {
+            Ok(md) => Response::build().raw_body(Body::Sized(file, md.len())).ok(),
+            Err(_) => Response::build().streamed_body(file).ok()
+        }
     }
 }