Updated HttpServer documentation to specify that only IPv6 connections can be made when specifying …

tests/standalone/io/http_loopback_test.dart

Index: tests/standalone/io/http_loopback_test.dart
diff --git a/tests/standalone/io/http_loopback_test.dart b/tests/standalone/io/http_loopback_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..eaa38ef0c96e0733da7c27879980882c44ed8210
--- /dev/null
+++ b/tests/standalone/io/http_loopback_test.dart
@@ -0,0 +1,81 @@
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import "dart:io";
+import "dart:async";
+import "package:expect/expect.dart";
+
+RawServerSocket server;
+RawSocket client;
+
+void serverListen(RawSocket serverSide) async {

[zra, 2017/06/08 21:45:21]

The analyzer will complain about this because async functions always return a
Future.

[bkonyi, 2017/06/08 22:49:37]

I've gone ahead and removed the void token from the async methods.

+  void serveData(RawSocketEvent event) async {

[zra, 2017/06/08 21:45:21]

ditto

[bkonyi, 2017/06/08 22:49:37]

Done.

+    serverSide.shutdown(SocketDirection.SEND);
+    await server.close();

[zra, 2017/06/08 21:45:21]

server is already closed below in the finally blocks, so it isn't needed here is
it?

[bkonyi, 2017/06/08 22:49:38]

You're right, I just forgot to remove this. Done.

+  }
+
+  serverSide.listen(serveData);
+}
+
+IPv4ToIPv6FailureTest() async {
+  server = await RawServerSocket.bind(InternetAddress.LOOPBACK_IP_V6, 0);
+  server.listen(serverListen);
+  bool testFailure = false;
+  try {
+    client =
+        await RawSocket.connect(InternetAddress.LOOPBACK_IP_V4, server.port);
+    await client.close();
+    testFailure = true;
+  } on SocketException catch (e) {
+    // We shouldn't be able to connect to the IPv6 loopback adapter using the
+    // IPv4 loopback address.
+  } catch (e) {
+    testFailure = true;
+  } finally {
+    Expect.equals(testFailure, false);
+    await server.close();
+  }
+}
+
+IPv6ToIPv4FailureTest() async {
+  server = await RawServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, 0);
+  server.listen(serverListen);
+  bool testFailure = false;
+  try {
+    client =
+        await RawSocket.connect(InternetAddress.LOOPBACK_IP_V6, server.port);
+    await client.close();
+    testFailure = true;
+  } on SocketException catch (e) {
+    // We shouldn't be able to connect to the IPv4 loopback adapter using the
+    // IPv6 loopback address.
+  } catch (e) {
+    testFailure = true;
+  } finally {
+    Expect.equals(testFailure, false);
+    await server.close();
+  }
+}
+
+loopbackSuccessTest(InternetAddress address) async {
+  server = await RawServerSocket.bind(address, 0);
+  server.listen(serverListen);
+  bool testFailure = false;
+  try {
+    client = await RawSocket.connect(address, server.port);
+    await client.close();
+  } catch (e) {
+    testFailure = true;
+  } finally {
+    Expect.equals(testFailure, false);
+    await server.close();
+  }
+}
+
+void main() async {
+  await IPv4ToIPv6FailureTest();
+  await IPv6ToIPv4FailureTest();
+  await loopbackSuccessTest(InternetAddress.LOOPBACK_IP_V4);
+  await loopbackSuccessTest(InternetAddress.LOOPBACK_IP_V6);
+}