Transformer plugin for polymer. This will make it possible (one day) to use

pkg/polymer/lib/src/build/common.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.
 
 /** Common methods used by transfomers. */
 library polymer.src.build.common;
 
 import 'dart:async';
 
 import 'package:barback/barback.dart';
@@ skipping 18 matching lines @@
   for (var e in parser.errors) {
     if (checkDocType || e.errorCode != 'expected-doctype-but-got-start-tag') {
       logger.warning(e.message, span: e.span);
     }
   }
   return document;
 }
 
 /** Additional options used by polymer transformers */
 class TransformOptions {
-  String currentPackage;
   List<String> entryPoints;
 
-  TransformOptions([this.currentPackage, entryPoints])
+  TransformOptions([entryPoints])
       : entryPoints = entryPoints == null ? null
           : entryPoints.map(_systemToAssetPath).toList();
 
   /** Whether an asset with [id] is an entry point HTML file. */
   bool isHtmlEntryPoint(AssetId id) {
     if (id.extension != '.html') return false;
 
     // Note: [id.path] is a relative path from the root of a package.
-    if (currentPackage == null || entryPoints == null) {
+    if (entryPoints == null) {
       return id.path.startsWith('web/') || id.path.startsWith('test/');
     }
 
-    return id.package == currentPackage && entryPoints.contains(id.path);
+    return entryPoints.contains(id.path);
   }
 }
 
 /** Mixin for polymer transformers. */
 abstract class PolymerTransformer {
   TransformOptions get options;
 
   Future<Document> readPrimaryAsHtml(Transform transform) {
     var asset = transform.primaryInput;
     var id = asset.id;
     return asset.readAsString().then((content) {
       return _parseHtml(content, id.path, transform.logger,
         checkDocType: options.isHtmlEntryPoint(id));
     });
   }
 
   Future<Document> readAsHtml(AssetId id, Transform transform) {
     var primaryId = transform.primaryInput.id;
-    var url = (id.package == primaryId.package) ? id.path
+    bool samePackage = id.package == primaryId.package;
+    var url = samePackage ? id.path
         : assetUrlFor(id, primaryId, transform.logger, allowAssetUrl: true);
     return transform.readInputAsString(id).then((content) {
       return _parseHtml(content, url, transform.logger,
-        checkDocType: options.isHtmlEntryPoint(id));
+        checkDocType: samePackage && options.isHtmlEntryPoint(id));
     });
   }
 
   Future<bool> assetExists(AssetId id, Transform transform) =>
       transform.getInput(id).then((_) => true).catchError((_) => false);
 }
 
 /** Create an [AssetId] for a [url] seen in the [source] asset. */
 // TODO(sigmund): delete once this is part of barback (dartbug.com/12610)
 AssetId resolve(AssetId source, String url, TransformLogger logger, Span span) {
@@ skipping 64 matching lines @@
   return builder.relative(builder.join('/', id.path),
       from: builder.join('/', builder.dirname(sourceId.path)));
 }
 
 
 /** Convert system paths to asset paths (asset paths are posix style). */
 String _systemToAssetPath(String assetPath) {
   if (path.Style.platform != path.Style.windows) return assetPath;
   return path.posix.joinAll(path.split(assetPath));
 }