Output the HTTPStatusException message as the response status phrase.

This has been the intent for the message parameter the whole time, but just now attracted attention, because in the HTTP/1.x server the status phrase has actually never been set appropriately.

source/vibe/http/common.d

@@ -332,8 +332,16 @@ class HTTPStatusException : Exception {
 		int m_status;
 	}
 
+	/** Construct a new exception corresponding to a particular HTTP status code.
+
+		Params:
+			status = The HTTP status code associated with the exception
+			message = HTTP status phrase sent together with the status code -
+				must be a single-line string
+	*/
 	this(int status, string message = null, string file = __FILE__, size_t line = __LINE__, Throwable next = null)
 	{
+		assert(message.indexOf('\n') < 0, "HTTP status phrase must be single-line!");
 		super(message.length ? message : httpStatusText(status), file, line, next);
 		m_status = status;
 	}

source/vibe/http/internal/http1/server.d

@@ -121,8 +121,11 @@ private bool handleRequest(TLSStreamType, Allocator)(StreamProxy http_stream, TC
 	void errorOut(int code, string msg, string debug_msg, Throwable ex)
 	@safe {
 		assert(!res.headerWritten);
+		assert(msg.length > 0 && !msg.canFind('\n'), "HTTP error status message must be a non-empty single-line string");
 
 		res.statusCode = code;
+		res.statusPhrase = msg;
+
 		if (settings && settings.errorPageHandler) {
 			/*scope*/ auto err = new HTTPServerErrorInfo;
 			err.code = code;

tests/vibe.http.server.statusexception/dub.sdl

@@ -0,0 +1,4 @@
+name "tests"
+description "Wrong host header tests"
+dependency "vibe-http" path="../../"
+versions "VibeDefaultMain"

tests/vibe.http.server.statusexception/source/app.d

@@ -0,0 +1,36 @@
+import vibe.core.core;
+import vibe.core.log : logInfo;
+import vibe.core.net;
+import vibe.http.server;
+import vibe.stream.operations;
+import core.time : msecs, seconds;
+import std.datetime : Clock, UTC;
+
+shared static this()
+{
+	auto s1 = new HTTPServerSettings;
+	s1.options &= ~HTTPServerOption.errorStackTraces;
+	s1.port = 0;
+	s1.bindAddresses = ["127.0.0.1"];
+	immutable serverAddr = listenHTTP(s1, &handler).bindAddresses[0];
+
+	runTask({
+		try {
+			auto conn = connectTCP(serverAddr);
+			conn.write("GET / HTTP/1.1\r\nHost: 127.0.0.1\r\nConnection: close\r\n\r\n");
+			string res = cast(string)conn.readLine();
+			assert(res == "HTTP/1.1 403 This is not accessible!", res);
+			while (conn.readLine().length > 0) {}
+			assert(cast(string)conn.readAllUTF8() == "403 - Forbidden\n\nThis is not accessible!");
+		} catch (Exception e) {
+			assert(false, e.msg);
+		}
+
+		scope (exit) exitEventLoop();
+	});
+}
+
+void handler(scope HTTPServerRequest req, scope HTTPServerResponse res)
+{
+	throw new HTTPStatusException(HTTPStatus.forbidden, "This is not accessible!");
+}