Fix SecureSocket tests to look up localhost only once, where possible.

tests/standalone/io/secure_server_socket_test.dart

 // Copyright (c) 2013, 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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 import "dart:async";
 import "dart:io";
 
 import "package:async_helper/async_helper.dart";
 import "package:expect/expect.dart";
-import "package:path/path.dart";
 
-const HOST_NAME = "localhost";
+InternetAddress HOST;
 const CERTIFICATE = "localhost_cert";
 
 void testSimpleBind() {
   asyncStart();
-  SecureServerSocket.bind(HOST_NAME, 0, CERTIFICATE).then((s) {
+  SecureServerSocket.bind(HOST, 0, CERTIFICATE).then((s) {
     Expect.isTrue(s.port > 0);
     s.close();
     asyncEnd();
   });
 }
 
 void testInvalidBind() {
   int count = 0;
 
   // Bind to a unknown DNS name.
   asyncStart();
   SecureServerSocket.bind("ko.faar.__hest__", 0, CERTIFICATE).then((_) {
     Expect.fail("Failure expected");
   }).catchError((error) {
     Expect.isTrue(error is SocketException);
     asyncEnd();
   });
 
   // Bind to an unavaliable IP-address.
   asyncStart();
   SecureServerSocket.bind("8.8.8.8", 0, CERTIFICATE).then((_) {
     Expect.fail("Failure expected");
   }).catchError((error) {
     Expect.isTrue(error is SocketException);
     asyncEnd();
   });
 
   // Bind to a port already in use.
   asyncStart();
-  SecureServerSocket.bind(HOST_NAME, 0, CERTIFICATE).then((s) {
-    SecureServerSocket.bind(HOST_NAME,
+  SecureServerSocket.bind(HOST, 0, CERTIFICATE).then((s) {
+    SecureServerSocket.bind(HOST,
                             s.port,
                             CERTIFICATE).then((t) {
       Expect.fail("Multiple listens on same port");
     }).catchError((error) {
       Expect.isTrue(error is SocketException);
       s.close();
       asyncEnd();
     });
   });
 }
 
 void testSimpleConnect(String certificate) {
   asyncStart();
-  SecureServerSocket.bind(HOST_NAME, 0, certificate).then((server) {
-    var clientEndFuture = SecureSocket.connect(HOST_NAME, server.port);
+  SecureServerSocket.bind(HOST, 0, certificate).then((server) {
+    var clientEndFuture = SecureSocket.connect(HOST, server.port);
     server.listen((serverEnd) {
       clientEndFuture.then((clientEnd) {
         clientEnd.close();
         serverEnd.close();
         server.close();
         asyncEnd();
       });
     });
   });
 }
 
 void testSimpleConnectFail(String certificate, bool cancelOnError) {
   asyncStart();
-  SecureServerSocket.bind(HOST_NAME, 0, certificate).then((server) {
-    var clientEndFuture = SecureSocket.connect(HOST_NAME, server.port)
+  SecureServerSocket.bind(HOST, 0, certificate).then((server) {
+    var clientEndFuture = SecureSocket.connect(HOST, server.port)
       .then((clientEnd) {
         Expect.fail("No client connection expected.");
       })
       .catchError((error) {
         Expect.isTrue(error is HandshakeException ||
                       error is SocketException);
       });
     server.listen((serverEnd) {
       Expect.fail("No server connection expected.");
     },
     onError: (error) {
       Expect.isTrue(error is CertificateException);
       clientEndFuture.then((_) {
         if (!cancelOnError) server.close();
         asyncEnd();
       });
     },
     cancelOnError: cancelOnError);
   });
 }
 
 void testServerListenAfterConnect() {
   asyncStart();
-  SecureServerSocket.bind(HOST_NAME, 0, CERTIFICATE).then((server) {
+  SecureServerSocket.bind(HOST, 0, CERTIFICATE).then((server) {
     Expect.isTrue(server.port > 0);
-    var clientEndFuture = SecureSocket.connect(HOST_NAME, server.port);
+    var clientEndFuture = SecureSocket.connect(HOST, server.port);
     new Timer(const Duration(milliseconds: 500), () {
       server.listen((serverEnd) {
         clientEndFuture.then((clientEnd) {
           clientEnd.close();
           serverEnd.close();
           server.close();
           asyncEnd();
         });
       });
     });
@@ skipping 18 matching lines @@
   }
 
   void verifyTestData(List<int> data) {
     Expect.equals(messageSize, data.length);
     List<int> expected = createTestData();
     for (int i = 0; i < messageSize; i++) {
       Expect.equals(expected[i], data[i]);
     }
   }
 
-  SecureServerSocket.bind(HOST_NAME, 0, CERTIFICATE).then((server) {
+  SecureServerSocket.bind(HOST, 0, CERTIFICATE).then((server) {
     server.listen((client) {
       int bytesRead = 0;
       int bytesWritten = 0;
       List<int> data = new List<int>(messageSize);
 
       client.listen(
         (buffer) {
           Expect.isTrue(bytesWritten == 0);
           data.setRange(bytesRead, bytesRead + buffer.length, buffer);
           bytesRead += buffer.length;
           if (bytesRead == data.length) {
             verifyTestData(data);
             client.add(data);
             client.close();
           }
         },
         onDone: () {
           server.close();
         });
     });
 
-    SecureSocket.connect(HOST_NAME, server.port).then((socket) {
+    SecureSocket.connect(HOST, server.port).then((socket) {
       int bytesRead = 0;
       int bytesWritten = 0;
       List<int> dataSent = createTestData();
       List<int> dataReceived = new List<int>(dataSent.length);
       socket.add(dataSent);
       socket.close();  // Can also be delayed.
       socket.listen(
         (List<int> buffer) {
           dataReceived.setRange(bytesRead, bytesRead + buffer.length, buffer);
           bytesRead += buffer.length;
         },
         onDone: () {
           verifyTestData(dataReceived);
           socket.close();
           asyncEnd();
         });
     });
   });
 }
 
 main() {
   asyncStart();
   String certificateDatabase = Platform.script.resolve('pkcert').toFilePath();
   SecureSocket.initialize(database: certificateDatabase,
                           password: 'dartdart',
                           useBuiltinRoots: false);
+  InternetAddress.lookup("localhost").then((hosts) {
+    HOST = hosts.first;
+    runTests();
+    asyncEnd();
+  });
+}
+
+runTests() {
   testSimpleBind();
   testInvalidBind();
   testSimpleConnect(CERTIFICATE);
   testSimpleConnect("CN=localhost");
   testSimpleConnectFail("not_a_nickname", false);
   testSimpleConnectFail("CN=notARealDistinguishedName", false);
   testSimpleConnectFail("not_a_nickname", true);
   testSimpleConnectFail("CN=notARealDistinguishedName", true);
   testServerListenAfterConnect();
   testSimpleReadWrite();
-  asyncEnd();
 }