Make the json_rpc_2 server test dart2js-compatible.

pkg/json_rpc_2/test/server/server_test.dart

 // Copyright (c) 2014, 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.
 
 library json_rpc_2.test.server.server_test;
 
 import 'dart:convert';
 
 import 'package:unittest/unittest.dart';
 import 'package:json_rpc_2/error_code.dart' as error_code;
@@ skipping 58 matching lines @@
       'id': 1234
     }), completion({
       'jsonrpc': '2.0',
       'id': 1234,
       'error': {
         'code': error_code.SERVER_ERROR,
         'message': 'bad format',
         'data': {
           'request': {'jsonrpc': '2.0', 'method': 'foo', 'id': 1234},
           'full': 'FormatException: bad format',
-          'stack': contains('server_test.dart')
+          'stack': new isInstanceOf<String>()
         }
       }
     }));
   });
 
   test("doesn't return a result for a notification", () {
     server.registerMethod('foo', (args) => 'result');
 
     expect(server.handleRequest({
       'jsonrpc': '2.0',
@@ skipping 26 matching lines @@
       });
 
       expect(server.parseRequest(JSON.encode({
         'jsonrpc': '2.0',
         'method': 'foo',
         'params': {'param': 'value'}
       })), completion(isNull));
     });
 
     test("a JSON parse error is rejected", () {
-      expect(server.parseRequest('invalid json {'),
-          completion(equals(JSON.encode({
-        'jsonrpc': '2.0',
-        'error': {
-          'code': error_code.PARSE_ERROR,
-          'message': "Invalid JSON: Unexpected character at 0: 'invalid json "
-                     "{'",
-          'data': {'request': 'invalid json {'}
-        },
-        'id': null
-      }))));
+      return server.parseRequest('invalid json {').then((result) {
+        expect(JSON.decode(result), {
+          'jsonrpc': '2.0',
+          'error': {
+            'code': error_code.PARSE_ERROR,
+            'message': startsWith("Invalid JSON: "),
+            'data': {'request': 'invalid json {'}
+          },
+          'id': null
+        });
+      });
     });
   });
 
   group("fallbacks", () {
     test("calls a fallback if no method matches", () {
       server.registerMethod('foo', () => 'foo');
       server.registerMethod('bar', () => 'foo');
       server.registerFallback((params) => {'fallback': params.value});
 
       expect(server.handleRequest({
@@ skipping 35 matching lines @@
         'id': 1234
       }), completion({
         'jsonrpc': '2.0',
         'id': 1234,
         'error': {
           'code': error_code.SERVER_ERROR,
           'message': 'bad format',
           'data': {
             'request': {'jsonrpc': '2.0', 'method': 'foo', 'id': 1234},
             'full': 'FormatException: bad format',
-            'stack': contains('server_test.dart')
+            'stack': new isInstanceOf<String>()
           }
         }
       }));
     });
   });
 
   test("disallows multiple methods with the same name", () {
     server.registerMethod('foo', () => null);
     expect(() => server.registerMethod('foo', () => null), throwsArgumentError);
   });
 }