Enabling adding and querying for source maps in a MappingBundle.

test/parser_test.dart

 // Copyright (c) 2013, 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 test.parser_test;
 
 import 'dart:convert';
 import 'package:test/test.dart';
 import 'package:source_maps/source_maps.dart';
 import 'package:source_span/source_span.dart';
@@ skipping 244 matching lines @@
           mapUrl: "file:///path/to/map");
 
       expect(mapping.spanFor(0, 0, uri: "output.dart").sourceUrl,
           Uri.parse("file:///path/to/pkg/input1.dart"));
       expect(mapping.spanFor(0, 0, uri: "output2.dart").sourceUrl,
           Uri.parse("file:///path/to/pkg/input2.dart"));
       expect(mapping.spanFor(0, 0, uri: "3/output.dart").sourceUrl,
           Uri.parse("file:///path/to/pkg/input3.dart"));
     });
 
+    test('build bundle incrementally', () {
+      var mapping = new MappingBundle();
+
+      mapping.addMapping(parseJson(MAP_WITH_SOURCE_LOCATION_AND_NAME_1,
+          mapUrl: "file:///path/to/map"));
+      expect(mapping.spanFor(0, 0, uri: "output.dart").sourceUrl,
+          Uri.parse("file:///path/to/pkg/input1.dart"));
+
+      expect(mapping.containsMapping("output2.dart"), isFalse);
+      mapping.addMapping(parseJson(MAP_WITH_SOURCE_LOCATION_AND_NAME_2,
+          mapUrl: "file:///path/to/map"));
+      expect(mapping.containsMapping("output2.dart"), isTrue);
+      expect(mapping.spanFor(0, 0, uri: "output2.dart").sourceUrl,
+          Uri.parse("file:///path/to/pkg/input2.dart"));
+
+      expect(mapping.containsMapping("3/output.dart"), isFalse);
+      mapping.addMapping(parseJson(MAP_WITH_SOURCE_LOCATION_AND_NAME_3,
+          mapUrl: "file:///path/to/map"));
+      expect(mapping.containsMapping("3/output.dart"), isTrue);
+      expect(mapping.spanFor(0, 0, uri: "3/output.dart").sourceUrl,
+          Uri.parse("file:///path/to/pkg/input3.dart"));
+    });
+
     // Test that the source map can handle cases where the uri passed in is
     // not from the expected host but it is still unambiguous which source
     // map should be used.
     test('different paths', () {
       expect(
           mapping
               .spanForLocation(new SourceLocation(0,
                   sourceUrl: Uri.parse('http://localhost/output.dart')))
               .sourceUrl,
           Uri.parse("file:///path/to/pkg/input1.dart"));
@@ skipping 37 matching lines @@
       mapping = parseJsonExtended(expected);
       expect(mapping.toJson(), equals(expected));
     }
     // Invalid for this case
     expect(() => parseJson(SOURCE_MAP_BUNDLE as dynamic), throws);
 
     var mapping = parseJsonExtended(SOURCE_MAP_BUNDLE);
     expect(mapping.toJson(), equals(SOURCE_MAP_BUNDLE));
   });
 }