From e3f317eea7f315d960dfd98e2ffa1462d5fd2cc0 Mon Sep 17 00:00:00 2001
From: Sean McArthur <sean.monstar@gmail.com>
Date: Wed, 25 Jan 2017 22:38:48 -0800
Subject: [PATCH] fix(header): enable SetCookie.fmt_header when only 1 cookie

---
 src/header/common/set_cookie.rs |  8 ++++++--
 src/header/mod.rs               | 14 +++++++++-----
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/header/common/set_cookie.rs b/src/header/common/set_cookie.rs
index 03b9f406a2..f2fd9efcb6 100644
--- a/src/header/common/set_cookie.rs
+++ b/src/header/common/set_cookie.rs
@@ -107,8 +107,12 @@ impl Header for SetCookie {
 }
 
 impl HeaderFormat for SetCookie {
-    fn fmt_header(&self, _f: &mut fmt::Formatter) -> fmt::Result {
-        panic!("SetCookie cannot be used with fmt_header, must use fmt_multi_header");
+    fn fmt_header(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        if self.0.len() == 1 {
+            write!(f, "{}", &self.0[0])
+        } else {
+            panic!("SetCookie with multiple cookies cannot be used with fmt_header, must use fmt_multi_header");
+        }
     }
 
     fn fmt_multi_header(&self, f: &mut ::header::MultilineFormatter) -> fmt::Result {
diff --git a/src/header/mod.rs b/src/header/mod.rs
index aa6520c016..0c3a24374f 100644
--- a/src/header/mod.rs
+++ b/src/header/mod.rs
@@ -539,28 +539,32 @@ impl<'a> FromIterator<HeaderView<'a>> for Headers {
 impl<'a> fmt::Display for &'a (HeaderFormat + Send + Sync) {
     #[inline]
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        (**self).fmt_header(f)
+        let mut multi = MultilineFormatter(Multi::Join(true, f));
+        self.fmt_multi_header(&mut multi)
     }
 }
 
 /// A wrapper around any Header with a Display impl that calls fmt_header.
 ///
 /// This can be used like so: `format!("{}", HeaderFormatter(&header))` to
-/// get the representation of a Header which will be written to an
-/// outgoing `TcpStream`.
+/// get the 'value string' representation of this Header.
+///
+/// Note: This may not necessarily be the value written to stream, such
+/// as with the SetCookie header.
 pub struct HeaderFormatter<'a, H: HeaderFormat>(pub &'a H);
 
 impl<'a, H: HeaderFormat> fmt::Display for HeaderFormatter<'a, H> {
     #[inline]
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt_header(f)
+        let mut multi = MultilineFormatter(Multi::Join(true, f));
+        self.0.fmt_multi_header(&mut multi)
     }
 }
 
 impl<'a, H: HeaderFormat> fmt::Debug for HeaderFormatter<'a, H> {
     #[inline]
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt_header(f)
+        fmt::Display::fmt(self, f)
     }
 }