Add a polymer validator: a linter/analysis that will replace the old

pkg/polymer/lib/src/transform/script_compactor.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.
 
 /** Transfomer that combines multiple dart script tags into a single one. */
 library polymer.src.transform.script_compactor;
 
 import 'dart:async';
 
 import 'package:barback/barback.dart';
@@ skipping 11 matching lines @@
  * support script tags with inlined code, use this transformer after running
  * [InlineCodeExtractor] on an earlier phase.
  *
  * Internally, this transformer will convert each script tag into an import
  * statement to a library, and then uses `initPolymer` (see polymer.dart)  to
  * invoke the main method on each of these libraries and register any polymer
  * elements annotated with `@CustomTag`.
  */
 class ScriptCompactor extends Transformer {
   /** Only run on entry point .html files. */
-  Future<bool> isPrimary(Asset input) => isPrimaryHtml(input.id);
+  Future<bool> isPrimary(Asset input) =>
+      new Future.value(isPrimaryHtml(input.id));
 
   Future apply(Transform transform) {
     var id = transform.primaryInput.id;
     var logger = transform.logger;
-    return transform.primaryInput.readAsString().then((content) {
-      var document = parseHtml(content, id.path, logger,
-          checkDocType: false);
+    return readPrimaryAsHtml(transform).then((document) {
       var libraries = [];
       bool changed = false;
       var dartLoaderTag = null;
       for (var tag in document.queryAll('script')) {
         var src = tag.attributes['src'];
         if (src != null) {
           if (src == 'packages/polymer/boot.js') {
             tag.remove();
             continue;
           }
@@ skipping 12 matching lines @@
           continue;
         }
         var libraryId = resolve(id, src, logger, tag.sourceSpan);
 
         // TODO(sigmund): should we detect/remove duplicates?
         if (libraryId == null) continue;
         libraries.add(libraryId);
       }
 
       if (!changed) {
-        transform.addOutput(new Asset.fromString(id, content));
+        transform.addOutput(transform.primaryInput);
         return;
       }
 
       var bootstrapId = id.addExtension('_bootstrap.dart');
       var filename = path.url.basename(bootstrapId.path);
 
       var bootstrapScript = parseFragment(
             '<script type="application/dart" src="$filename"></script>');
       if (dartLoaderTag == null) {
         document.body.nodes.add(bootstrapScript);
         document.body.nodes.add(parseFragment(
             '<script src="packages/browser/dart.js"></script>'));
       } else if (dartLoaderTag.parent != document.body) {
         document.body.nodes.add(bootstrapScript);
       } else {
         document.body.insertBefore(bootstrapScript, dartLoaderTag);
       }
 
-      var urls = libraries.map((id) => importUrlFor(id, bootstrapId, logger))
+      var urls = libraries.map((id) => assetUrlFor(id, bootstrapId, logger))
           .where((url) => url != null).toList();
       var buffer = new StringBuffer()..write(_header);
       for (int i = 0; i < urls.length; i++) {
         buffer.writeln("import '${urls[i]}' as i$i;");
       }
       buffer..write(_mainPrefix)
           ..writeAll(urls.map((url) => "      '$url',\n"))
           ..write(_mainSuffix);
 
       transform.addOutput(new Asset.fromString(bootstrapId, buffer.toString()));
       transform.addOutput(new Asset.fromString(id, document.outerHtml));
     });
   }
-
-  /**
-   * Generate the import url for a file described by [id], referenced by a file
-   * with [sourceId].
-   */
-  String importUrlFor(AssetId id, AssetId sourceId, TransformLogger logger) {
-    // use package: urls if possible
-    if (id.path.startsWith('lib/')) {
-      return 'package:${id.package}/${id.path.substring(4)}';
-    }
-
-    // Use relative urls only if it's possible.
-    if (id.package != sourceId.package) {
-      logger.error("don't know how to import $id from $sourceId");
-      return null;
-    }
-
-    var builder = path.url;
-    return builder.relative(builder.join('/', id.path),
-        from: builder.join('/', builder.dirname(sourceId.path)));
-  }
 }
 
 const _header = """
 library app_bootstrap;
 
 import 'package:polymer/polymer.dart';
 import 'dart:mirrors' show currentMirrorSystem;
 
 """;
 
 const _mainPrefix = """
 
 void main() {
   initPolymer([
 """;
 
 // TODO(sigmund): investigate alternative to get the baseUri (dartbug.com/12612)
 const _mainSuffix = """
     ], currentMirrorSystem().isolate.rootLibrary.uri.toString());
 }
 """;