Add a path.formatUri method and release path 1.2.0.

pkg/path/test/url_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.
 
 import 'package:unittest/unittest.dart';
 import 'package:path/path.dart' as path;
 
 main() {
   var context = new path.Context(style: path.Style.url,
       current: 'http://dartlang.org/root/path');
@@ skipping 723 matching lines @@
     expect(context.toUri('foo/bar'), Uri.parse('foo/bar'));
     expect(context.toUri('http://dartlang.org/path/to/foo%23bar'),
         Uri.parse('http://dartlang.org/path/to/foo%23bar'));
     // Since the input path is also a URI, special characters should already
     // be percent encoded there too.
     expect(context.toUri(r'http://foo.com/_%7B_%7D_%60_%5E_%20_%22_%25_'),
         Uri.parse('http://foo.com/_%7B_%7D_%60_%5E_%20_%22_%25_'));
     expect(context.toUri(r'_%7B_%7D_%60_%5E_%20_%22_%25_'),
         Uri.parse('_%7B_%7D_%60_%5E_%20_%22_%25_'));
   });
+
+  group('prettyUri', () {
+    test('with a file: URI', () {
+      expect(context.prettyUri(Uri.parse('file:///root/path/a/b')),
+          'file:///root/path/a/b');
+    });
+
+    test('with an http: URI', () {
+      expect(context.prettyUri('http://dartlang.org/root/path/a/b'), 'a/b');
+      expect(context.prettyUri('http://dartlang.org/root/path/a/../b'), 'b');
+      expect(context.prettyUri('http://dartlang.org/other/path/a/b'),
+          'http://dartlang.org/other/path/a/b');
+      expect(context.prettyUri('http://pub.dartlang.org/root/path'),
+          'http://pub.dartlang.org/root/path');
+      expect(context.prettyUri('http://dartlang.org/root/other'),
+          '../other');
+    });
+
+    test('with a relative URI', () {
+      expect(context.prettyUri('a/b'), 'a/b');
+    });
+
+    test('with a root-relative URI', () {
+      expect(context.prettyUri('/a/b'), '/a/b');
+    });
+
+    test('with a Uri object', () {
+      expect(context.prettyUri(Uri.parse('a/b')), 'a/b');
+    });
+  });
 }