Make pub publish more user friendly:

utils/tests/pub/path/path_posix_test.dart

 // Copyright (c) 2012, 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 path_test;
 
 import 'dart:io' as io;
 
 import '../../../../pkg/unittest/lib/unittest.dart';
 import '../../../pub/path.dart' as path;
@@ skipping 135 matching lines @@
     });
 
     test('disallows intermediate nulls', () {
       expect(() => builder.join('a', null, 'b'), throwsArgumentError);
       expect(() => builder.join(null, 'a'), throwsArgumentError);
     });
   });
 
   group('split', () {
     test('simple cases', () {
+      expect(builder.split(''), []);
+      expect(builder.split('.'), ['.']);
+      expect(builder.split('..'), ['..']);
       expect(builder.split('foo'), equals(['foo']));
-      expect(builder.split('foo/bar'), equals(['foo', 'bar']));
+      expect(builder.split('foo/bar.txt'), equals(['foo', 'bar.txt']));
       expect(builder.split('foo/bar/baz'), equals(['foo', 'bar', 'baz']));
       expect(builder.split('foo/../bar/./baz'),
           equals(['foo', '..', 'bar', '.', 'baz']));
       expect(builder.split('foo//bar///baz'), equals(['foo', 'bar', 'baz']));
       expect(builder.split('foo/\\/baz'), equals(['foo', '\\', 'baz']));
       expect(builder.split('.'), equals(['.']));
       expect(builder.split(''), equals([]));
       expect(builder.split('foo/'), equals(['foo']));
       expect(builder.split('//'), equals(['/']));
     });
@@ skipping 181 matching lines @@
     expect(builder.withoutExtension('a/'), 'a/');
     expect(builder.withoutExtension('a/b/'), 'a/b/');
     expect(builder.withoutExtension('a/.'), 'a/.');
     expect(builder.withoutExtension('a/.b'), 'a/.b');
     expect(builder.withoutExtension('a.b/c'), 'a.b/c');
     expect(builder.withoutExtension(r'a.b\c'), r'a');
     expect(builder.withoutExtension(r'a/b\c'), r'a/b\c');
     expect(builder.withoutExtension(r'a/b\c.d'), r'a/b\c');
   });
 }