Tidy up empty_body writer error

include/beast/http/empty_body.hpp

@@ -16,11 +16,15 @@
 namespace beast {
 namespace http {
 
-/** An empty message body
+/** An empty message body.
 
-    Meets the requirements of @b Body.
+    This body is used to represent messages which do not have a
+    message body. If this body is used with a parser, and the
+    parser encounters octets corresponding to a message body,
+    the parser will fail with the error @ref http::unexpected_body.
 
-    @note This body type may only be written, not read.
+    Meets the requirements of @b Body. The Content-Length of this
+    body is always 0.
 */
 struct empty_body
 {
@@ -91,7 +95,7 @@ struct empty_body
         put(ConstBufferSequence const&,
             error_code& ec)
         {
-            ec = error::missing_body;
+            ec = error::unexpected_body;
         }
 
         void

include/beast/http/error.hpp

@@ -47,7 +47,7 @@ enum class error
     */
     need_more,
 
-    /** The message container has no body.
+    /** An unexpected body was encountered during parsing.
 
         This error is returned when attempting to parse body
         octets into a message container which has the
@@ -55,7 +55,7 @@ enum class error
 
         @see @ref empty_body
     */
-    missing_body,
+    unexpected_body,
 
     /** Additional buffers are required.
 

test/http/error.cpp

@@ -39,7 +39,10 @@ public:
         check("http", error::end_of_stream);
         check("http", error::partial_message);
         check("http", error::need_more);
+        check("http", error::unexpected_body);
+        check("http", error::need_buffer);
         check("http", error::buffer_overflow);
+
         check("http", error::bad_line_ending);
         check("http", error::bad_method);
         check("http", error::bad_path);