Rationalize arg handling for pub build and serve.

sdk/lib/_internal/pub/test/serve/utils.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS d.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.
 
 library pub_tests;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
@@ skipping 340 matching lines @@
       return _jsonRpcRequest(method, resolvedParams);
     }).then((response) {
       expect(response["error"]["code"], errorCode);
       expect(response["error"]["message"], errorMessage);
 
       return response["error"]["data"];
     });
   }, "send $method with $params to web socket and expect error $errorCode");
 }
 
+/// Validates that [root] was not bound to a port when pub serve started.
+Future expectNotServed(String root) {
+  return schedule(() {
+    expect(_ports.containsKey(root), isFalse);
+  });
+}
+
 /// The next id to use for a JSON-RPC 2.0 request.
 var _rpcId = 0;
 
 /// Sends a JSON-RPC 2.0 request calling [method] with [params].
 ///
 /// Returns the response object.
 Future<Map> _jsonRpcRequest(String method, Map params) {
   var id = _rpcId++;
   _webSocket.add(JSON.encode({
     "jsonrpc": "2.0",
@@ skipping 36 matching lines @@
 /// included. Unlike [getServerUrl], this should only be called after the ports
 /// are known.
 String _getServerUrlSync([String root, String path]) {
   if (root == null) root = 'web';
   expect(_ports, contains(root));
   var url = "http://127.0.0.1:${_ports[root]}";
   if (path != null) url = "$url/$path";
   return url;
 }