Tests for exceptional situations in MemoryResourceProvider.

pkg/analysis_server/test/resource_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 test.resource;
 
 import 'dart:io' as io;
 
 import 'package:analysis_server/src/resource.dart';
 import 'package:analyzer/src/generated/engine.dart' show TimestampedData;
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:path/path.dart';
 import 'package:unittest/unittest.dart';
 
 main() {
   groupSep = ' | ';
 
   group('MemoryResourceProvider', () {
     MemoryResourceProvider provider;
 
     setUp(() {
       provider = new MemoryResourceProvider();
     });
 
+    test('MemoryResourceException', () {
+      var exception = new MemoryResourceException('/my/path', 'my message');
+      expect(exception.path, '/my/path');
+      expect(exception.message, 'my message');
+      expect(exception.toString(),
+          'MemoryResourceException(path=/my/path; message=my message)');
+    });
+
+    group('newFolder', () {
+      test('empty path', () {
+        expect(
+          () {
+            provider.newFolder('');
+          },
+          throwsA(new isInstanceOf<ArgumentError>())
+        );
+      });
+
+      test('not absolute', () {
+        expect(
+          () {
+            provider.newFolder('not/absolute');
+          },
+          throwsA(new isInstanceOf<ArgumentError>())
+        );
+      });
+
+      group('already exists', () {
+        test('as folder', () {
+          Folder folder = provider.newFolder('/my/folder');
+          Folder newFolder = provider.newFolder('/my/folder');
+          expect(newFolder, folder);
+        });
+
+        test('as file', () {

[Brian Wilkerson, 2014/05/27 19:32:26]

Is it worth testing the creation of a file when a folder already exists?

+          File file = provider.newFile('/my/file', 'qwerty');
+          expect(
+            () {
+            provider.newFolder('/my/file');
+            },
+            throwsA(new isInstanceOf<ArgumentError>())
+          );
+        });
+      });
+    });
+
     group('File', () {
       group('==', () {
         test('false', () {
           File fileA = provider.getResource('/fileA.txt');
           File fileB = provider.getResource('/fileB.txt');
           expect(fileA == new Object(), isFalse);
           expect(fileA == fileB, isFalse);
         });
 
         test('true', () {
@@ skipping 277 matching lines @@
         expect(children[1], _isFolder);
         expect(children[2], _isFile);
       });
     });
   });
 }
 
 var _isFile = new isInstanceOf<File>();
 var _isFolder = new isInstanceOf<Folder>();
 var _isMemoryResourceException = new isInstanceOf<MemoryResourceException>();