Fix lingering references to the old Span in yaml.

pkg/yaml/test/yaml_node_wrapper_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 yaml.node_wrapper_test;
 
 import 'package:source_maps/source_maps.dart';
 import 'package:unittest/unittest.dart';
 import 'package:yaml/yaml.dart';
 
 main() {
   test("YamlMap() with no sourceUrl", () {
     var map = new YamlMap();
     expect(map, isEmpty);
     expect(map.nodes, isEmpty);
     expect(map.span, isNullSpan(isNull));
   });
 
   test("YamlMap() with a sourceUrl", () {
     var map = new YamlMap(sourceUrl: "source");
-    expect(map.span, isNullSpan("source"));
+    expect(map.span, isNullSpan(Uri.parse("source")));
   });
 
   test("YamlList() with no sourceUrl", () {
     var list = new YamlList();
     expect(list, isEmpty);
     expect(list.nodes, isEmpty);
     expect(list.span, isNullSpan(isNull));
   });
 
   test("YamlList() with a sourceUrl", () {
     var list = new YamlList(sourceUrl: "source");
-    expect(list.span, isNullSpan("source"));
+    expect(list.span, isNullSpan(Uri.parse("source")));
   });
 
   test("YamlMap.wrap() with no sourceUrl", () {
     var map = new YamlMap.wrap({
       "list": [1, 2, 3],
       "map": {
         "foo": "bar",
         "nested": [4, 5, 6]
       },
       "scalar": "value"
@@ skipping 28 matching lines @@
   test("YamlMap.wrap() with a sourceUrl", () {
     var map = new YamlMap.wrap({
       "list": [1, 2, 3],
       "map": {
         "foo": "bar",
         "nested": [4, 5, 6]
       },
       "scalar": "value"
     }, sourceUrl: "source");
 
-    expect(map.span, isNullSpan("source"));
-    expect(map["list"].span, isNullSpan("source"));
-    expect(map["map"].span, isNullSpan("source"));
-    expect(map.nodes["scalar"].span, isNullSpan("source"));
+    var source = Uri.parse("source");
+    expect(map.span, isNullSpan(source));
+    expect(map["list"].span, isNullSpan(source));
+    expect(map["map"].span, isNullSpan(source));
+    expect(map.nodes["scalar"].span, isNullSpan(source));
   });
 
   test("YamlList.wrap() with no sourceUrl", () {
     var list = new YamlList.wrap([
       [1, 2, 3],
       {
         "foo": "bar",
         "nested": [4, 5, 6]
       },
       "value"
@@ skipping 31 matching lines @@
       },
       "value"
     ]);
 
     expect(list.span, isNullSpan(isNull));
     expect(list[0].span, isNullSpan(isNull));
     expect(list[1].span, isNullSpan(isNull));
     expect(list.nodes[2].span, isNullSpan(isNull));
   });
 
-  solo_test("re-wrapped objects equal one another", () {
+  test("re-wrapped objects equal one another", () {
     var list = new YamlList.wrap([
       [1, 2, 3],
       {"foo": "bar"}
     ]);
 
     expect(list[0] == list[0], isTrue);
     expect(list[0].nodes == list[0].nodes, isTrue);
     expect(list[0] == new YamlList.wrap([1, 2, 3]), isFalse);
     expect(list[1] == list[1], isTrue);
     expect(list[1].nodes == list[1].nodes, isTrue);
     expect(list[1] == new YamlMap.wrap({"foo": "bar"}), isFalse);
   });
 }
 
 Matcher isNullSpan(sourceUrl) => predicate((span) {
-  expect(span, new isInstanceOf<Span>());
+  expect(span, new isInstanceOf<SourceSpan>());
   expect(span.length, equals(0));
   expect(span.text, isEmpty);
-  expect(span.isIdentifier, isFalse);
   expect(span.start, equals(span.end));
   expect(span.start.offset, equals(0));
   expect(span.start.line, equals(0));
   expect(span.start.column, equals(0));
   expect(span.sourceUrl, sourceUrl);
   return true;
 });