Add Resource.delete() method.

pkg/analyzer/test/file_system/memory_file_system_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 analyzer.test.file_system.memory_file_system_test;
 
 import 'dart:async';
 import 'dart:core' hide Resource;
 
 import 'package:analyzer/file_system/file_system.dart';
@@ skipping 30 matching lines @@
     expect(exception.message, 'my message');
     expect(exception.toString(),
         'FileSystemException(path=/my/path; message=my message)');
   }
 }
 
 @reflectiveTest
 class FileTest {
   MemoryResourceProvider provider = new MemoryResourceProvider();
 
+  void test_delete() {
+    File file = provider.newFile('/foo/file.txt', 'content');
+    expect(file.exists, isTrue);
+    // delete
+    file.delete();
+    expect(file.exists, isFalse);
+  }
+
   void test_equals_beforeAndAfterCreate() {
     String path = '/file.txt';
     File file1 = provider.getResource(path);
     provider.newFile(path, 'contents');
     File file2 = provider.getResource(path);
     expect(file1 == file2, isTrue);
   }
 
   void test_equals_false() {
     File fileA = provider.getResource('/fileA.txt');
@@ skipping 173 matching lines @@
     expect(folder.canonicalizePath('/a/b/./c'), equals('/a/b/c'));
   }
 
   void test_contains() {
     expect(folder.contains('/foo/bar/aaa.txt'), isTrue);
     expect(folder.contains('/foo/bar/aaa/bbb.txt'), isTrue);
     expect(folder.contains('/baz.txt'), isFalse);
     expect(folder.contains('/foo/bar'), isFalse);
   }
 
+  void test_delete() {
+    Folder folder = provider.newFolder('/foo');
+    Folder barFolder = provider.newFolder('/foo/bar');
+    File aFile = provider.newFile('/foo/bar/a.txt', '');
+    File bFile = provider.newFile('/foo/b.txt', '');
+    expect(folder.exists, isTrue);
+    expect(barFolder.exists, isTrue);
+    expect(aFile.exists, isTrue);
+    expect(bFile.exists, isTrue);
+    // delete 'folder'
+    folder.delete();
+    expect(folder.exists, isFalse);
+    expect(barFolder.exists, isFalse);
+    expect(aFile.exists, isFalse);
+    expect(bFile.exists, isFalse);
+  }
+
   void test_equal_false() {
     String path2 = '/foo/baz';
     Folder folder2 = provider.newFolder(path2);
     expect(folder == folder2, isFalse);
   }
 
   void test_equal_true() {
     Folder folder2 = provider.getResource(path);
     expect(folder == folder2, isTrue);
   }
@@ skipping 405 matching lines @@
     return new Future.delayed(Duration.ZERO, computation);
   }
 
   _watchingFolder(String path, test(List<WatchEvent> changesReceived)) {
     Folder folder = provider.getResource(path);
     var changesReceived = <WatchEvent>[];
     folder.changes.listen(changesReceived.add);
     return test(changesReceived);
   }
 }