Fix minor path handling issue in path package.

pkg/path/test/path_windows_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 'package:unittest/unittest.dart';
 import 'package:path/path.dart' as path;
@@ skipping 198 matching lines @@
       // expect(builder.split(r'\\server\'), equals([r'\\server\']));
     });
   });
 
   group('normalize', () {
     test('simple cases', () {
       expect(builder.normalize(''), '');
       expect(builder.normalize('.'), '.');
       expect(builder.normalize('..'), '..');
       expect(builder.normalize('a'), 'a');
-      expect(builder.normalize('C:/'), r'C:/');
+      expect(builder.normalize('C:/'), r'C:\');
       expect(builder.normalize(r'C:\'), r'C:\');
       expect(builder.normalize(r'\\'), r'\\');
     });
 
     test('collapses redundant separators', () {
       expect(builder.normalize(r'a\b\c'), r'a\b\c');
       expect(builder.normalize(r'a\\b\\\c\\\\d'), r'a\b\c\d');
     });
 
     test('eliminates "." parts', () {
@@ skipping 13 matching lines @@
     test('eliminates ".." parts', () {
       expect(builder.normalize('..'), '..');
       expect(builder.normalize(r'..\'), '..');
       expect(builder.normalize(r'..\..\..'), r'..\..\..');
       expect(builder.normalize(r'../..\..\'), r'..\..\..');
       // TODO(rnystrom): Is this how Python handles absolute paths on Windows?
       expect(builder.normalize(r'\\..'), r'\\');
       expect(builder.normalize(r'\\..\..\..'), r'\\');
       expect(builder.normalize(r'\\..\../..\a'), r'\\a');
       expect(builder.normalize(r'c:\..'), r'c:\');
-      expect(builder.normalize(r'A:/..\..\..'), r'A:/');
+      expect(builder.normalize(r'A:/..\..\..'), r'A:\');
       expect(builder.normalize(r'b:\..\..\..\a'), r'b:\a');
       expect(builder.normalize(r'a\..'), '.');
       expect(builder.normalize(r'a\b\..'), 'a');
       expect(builder.normalize(r'a\..\b'), 'b');
       expect(builder.normalize(r'a\.\..\b'), 'b');
       expect(builder.normalize(r'a\b\c\..\..\d\e\..'), r'a\d');
       expect(builder.normalize(r'a\b\..\..\..\..\c'), r'..\..\c');
     });
 
     test('removes trailing separators', () {
@@ skipping 11 matching lines @@
 
   group('relative', () {
     group('from absolute root', () {
       test('given absolute path in root', () {
         expect(builder.relative(r'C:\'), r'..\..');
         expect(builder.relative(r'C:\root'), '..');
         expect(builder.relative(r'C:\root\path'), '.');
         expect(builder.relative(r'C:\root\path\a'), 'a');
         expect(builder.relative(r'C:\root\path\a\b.txt'), r'a\b.txt');
         expect(builder.relative(r'C:\root\a\b.txt'), r'..\a\b.txt');
+        expect(builder.relative(r'C:/'), r'..\..');
+        expect(builder.relative(r'C:/root'), '..');
+        expect(builder.relative(r'c:\'), r'..\..');
+        expect(builder.relative(r'c:\root'), '..');
       });
 
       test('given absolute path outside of root', () {
         expect(builder.relative(r'C:\a\b'), r'..\..\a\b');
         expect(builder.relative(r'C:\root\path\a'), 'a');
         expect(builder.relative(r'C:\root\path\a\b.txt'), r'a\b.txt');
         expect(builder.relative(r'C:\root\a\b.txt'), r'..\a\b.txt');
+        expect(builder.relative(r'C:/a/b'), r'..\..\a\b');
+        expect(builder.relative(r'C:/root/path/a'), 'a');
+        expect(builder.relative(r'c:\a\b'), r'..\..\a\b');
+        expect(builder.relative(r'c:\root\path\a'), 'a');
       });
 
       test('given absolute path on different drive', () {
         expect(builder.relative(r'D:\a\b'), r'D:\a\b');
       });
 
       test('given relative path', () {
         // The path is considered relative to the root, so it basically just
         // normalizes.
         expect(builder.relative(''), '.');
@@ skipping 95 matching lines @@
     expect(builder.withoutExtension(r'a\.'), r'a\.');
     expect(builder.withoutExtension(r'a\.b'), r'a\.b');
     expect(builder.withoutExtension(r'a.b\c'), r'a.b\c');
     expect(builder.withoutExtension(r'a/b.c/d'), r'a/b.c/d');
     expect(builder.withoutExtension(r'a\b/c'), r'a\b/c');
     expect(builder.withoutExtension(r'a\b/c.d'), r'a\b/c');
     expect(builder.withoutExtension(r'a.b/c'), r'a.b/c');
     expect(builder.withoutExtension(r'a\b.c\'), r'a\b\');
   });
 }