anchor.diff:  
     @failingTest
     test_file_importedLibrary_sideways() async {
  +    fail('Not yet implemented/tested');
       String pathA = '/project/000/1111/a.dart';
       testFile = '/project/000/1111/sub/folder/test.dart';
       addSource(pathA, '''
  
positive.code: 
    @failingTest
    test_file_importedLibrary_package() async {
      // configure packages
      testFile = '/packages/my_pkg/lib/aaa/test.dart';
      newFile(testFile, content: '');
  
negative.code: 
    @failingTest
    test_file_referenced_by_multiple_libraries() async {
      fail('Not yet implemented/tested');
      String pathA = '/project/000/1111/a.dart';
      String pathB = '/project/000/b.dart';
      testFile = '/project/000/1111/22/test.dart';
  