Change package scheduled_test to throw TestFailures rather than strings.

pkg/scheduled_test/test/descriptor/directory_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.
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:path/path.dart' as path;
 import 'package:scheduled_test/descriptor.dart' as d;
 import 'package:scheduled_test/scheduled_test.dart';
@@ skipping 282 matching lines @@
 
   expectTestsPass("directory().load() fails to load a nested directory", () {
     test('test', () {
       var dir = d.dir('dir', [
         d.dir('subdir', [
           d.file('name.txt', 'subcontents')
         ]),
         d.file('name.txt', 'contents')
       ]);
 
-      expect(dir.load('subdir').toList(),
-          throwsA(equals("Couldn't find a readable entry named 'subdir' within "
-              "'dir'.")));
+      expect(dir.load('subdir').toList(), throwsA(predicate(
+          (x) => x.toString() == "Couldn't find a readable entry named "
+                                 "'subdir' within 'dir'.")));
     });
   });
 
   expectTestsPass("directory().load() fails to load an absolute path", () {
     test('test', () {
       var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
 
       expect(dir.load('/name.txt').toList(), throwsArgumentError);
     });
   });
 
   expectTestsPass("directory().load() fails to load '.', '..', or ''", () {
     test('test', () {
       var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
 
       expect(dir.load('.').toList(), throwsArgumentError);
 
       expect(dir.load('..').toList(), throwsArgumentError);
 
       expect(dir.load('').toList(), throwsArgumentError);
     });
   });
 
   expectTestsPass("directory().load() fails to load a file that doesn't exist",
       () {
     test('test', () {
       var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
 
-      expect(dir.load('not-name.txt').toList(),
-          throwsA(equals("Couldn't find a readable entry named 'not-name.txt' "
-              "within 'dir'.")));
+      expect(dir.load('not-name.txt').toList(), throwsA(predicate(
+          (x) => x.toString() == "Couldn't find a readable entry named "
+                                 "'not-name.txt' within 'dir'.")));
     });
   });
 
   expectTestsPass("directory().load() fails to load a file that exists "
       "multiple times", () {
     test('test', () {
       var dir = d.dir('dir', [
         d.file('name.txt', 'contents'),
         d.file('name.txt', 'contents')
       ]);
 
-      expect(dir.load('name.txt').toList(),
-          throwsA(equals("Found multiple readable entries named 'name.txt' "
-              "within 'dir'.")));
+      expect(dir.load('name.txt').toList(), throwsA(predicate(
+          (x) => x.toString() == "Found multiple readable entries named "
+                                 "'name.txt' within 'dir'.")));
     });
   });
 
   expectTestsPass("directory().load() loads a file next to a subdirectory with "
       "the same name", () {
     test('test', () {
       var dir = d.dir('dir', [
         d.file('name', 'contents'),
         d.dir('name', [d.file('subfile', 'contents')])
       ]);
@@ skipping 44 matching lines @@
           "'-- file2.txt"));
     });
   });
 
   expectTestsPass("directory().describe() with no contents returns the "
       "directory name", () {
     test('test', () {
       expect(d.dir('dir').describe(), equals('dir'));
     });
   });
-}
+}