Share code between the transformer isolate and pub proper.

sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart

Index: sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart
diff --git a/sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart b/sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart
index 70b6151f0bc974da8b6e2d15327e03617d77969b..61b2563c654efef7436eb4db10da5158a3ec6511 100644
--- a/sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart
+++ b/sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart
@@ -11,13 +11,10 @@ import 'dart:isolate';
 import 'package:barback/barback.dart';
 // TODO(nweiz): don't import from "src" once issue 14966 is fixed.
 import 'package:barback/src/internal_asset.dart';
-import 'package:path/path.dart' as p;
-import 'package:source_maps/source_maps.dart';
-import 'package:stack_trace/stack_trace.dart';
 
+import '../../../asset/dart/serialize.dart';
 import '../barback.dart';
 import '../dart.dart' as dart;
-import '../io.dart';
 import '../log.dart' as log;
 import '../utils.dart';
 import 'build_environment.dart';
@@ -49,7 +46,7 @@ Future<Set> loadTransformers(BuildEnvironment environment,
     return dart.runInIsolate(code, port.sendPort)
         .then((_) => port.first)
         .then((sendPort) {
-      return _call(sendPort, {
+      return call(sendPort, {
         'library': uri,
         'mode': environment.mode.name,
         // TODO(nweiz): support non-JSON-encodable configuration maps.
@@ -62,7 +59,7 @@ Future<Set> loadTransformers(BuildEnvironment environment,
         return transformers;
       });
     }).catchError((error, stackTrace) {
-      if (error is! dart.CrossIsolateException) throw error;
+      if (error is! CrossIsolateException) throw error;
       if (error.type != 'IsolateSpawnException') throw error;
       // TODO(nweiz): don't parse this as a string once issues 12617 and 12689
       // are fixed.
@@ -95,16 +92,16 @@ class _ForeignTransformer extends Transformer {
         _toString = map['toString'];
 
   Future<bool> isPrimary(Asset asset) {
-    return _call(_port, {
+    return call(_port, {
       'type': 'isPrimary',
       'asset': serializeAsset(asset)
     });
   }
 
   Future apply(Transform transform) {
-    return _call(_port, {
+    return call(_port, {
       'type': 'apply',
-      'transform': _serializeTransform(transform)
+      'transform': serializeTransform(transform)
     });
   }
 
@@ -138,160 +135,3 @@ _deserializeTransformerOrGroup(Map map, TransformerId id) {
   assert(map['type'] == 'TransformerGroup');
   return new _ForeignGroup(id, map);
 }
-
-/// Converts [transform] into a serializable map.
-Map _serializeTransform(Transform transform) {
-  var receivePort = new ReceivePort();
-  receivePort.listen((wrappedMessage) {
-    _respond(wrappedMessage, (message) {
-      if (message['type'] == 'getInput') {
-        return transform.getInput(_deserializeId(message['id']))
-            .then((asset) => serializeAsset(asset));
-      }
-
-      if (message['type'] == 'addOutput') {
-        transform.addOutput(deserializeAsset(message['output']));
-        return null;
-      }
-
-      if (message['type'] == 'consumePrimary') {
-        transform.consumePrimary();
-        return null;
-      }
-
-      assert(message['type'] == 'log');
-      var method;
-      if (message['level'] == 'Info') {
-        method = transform.logger.info;
-      } else if (message['level'] == 'Fine') {
-        method = transform.logger.fine;
-      } else if (message['level'] == 'Warning') {
-        method = transform.logger.warning;
-      } else {
-        assert(message['level'] == 'Error');
-        method = transform.logger.error;
-      }
-
-      var assetId = message['assetId'] == null ? null :
-        _deserializeId(message['assetId']);
-      var span = message['span'] == null ? null :
-        _deserializeSpan(message['span']);
-      method(message['message'], asset: assetId, span: span);
-    });
-  });
-
-  return {
-    'port': receivePort.sendPort,
-    'primaryInput': serializeAsset(transform.primaryInput)
-  };
-}
-
-/// Converts a serializable map into an [AssetId].
-AssetId _deserializeId(Map id) => new AssetId(id['package'], id['path']);
-
-/// Converts a serializable map into a [Span].
-Span _deserializeSpan(Map span) {
-  assert(span['type'] == 'fixed');
-  var location = _deserializeLocation(span['start']);
-  return new FixedSpan(span['sourceUrl'], location.offset, location.line,
-      location.column, text: span['text'], isIdentifier: span['isIdentifier']);
-}
-
-/// Converts a serializable map into a [Location].
-Location _deserializeLocation(Map location) {
-  assert(location['type'] == 'fixed');
-  return new FixedLocation(location['offset'], location['sourceUrl'],
-      location['line'], location['column']);
-}
-
-/// Converts [id] into a serializable map.
-Map _serializeId(AssetId id) => {'package': id.package, 'path': id.path};
-
-/// Responds to a message sent by [_call].
-///
-/// [wrappedMessage] is the raw message sent by [_call]. This unwraps it and
-/// passes the contents of the message to [callback], then sends the return
-/// value of [callback] back to [_call]. If [callback] returns a Future or
-/// throws an error, that will also be sent.
-void _respond(wrappedMessage, callback(message)) {
-  var replyTo = wrappedMessage['replyTo'];
-  syncFuture(() => callback(wrappedMessage['message']))
-      .then((result) => replyTo.send({'type': 'success', 'value': result}))
-      .catchError((error, stackTrace) {
-    replyTo.send({
-      'type': 'error',
-      'error': _serializeException(error, stackTrace)
-    });
-  });
-}
-
-/// Wraps [message] and sends it across [port], then waits for a response which
-/// should be sent using [_respond].
-///
-/// The returned Future will complete to the value or error returned by
-/// [_respond].
-Future _call(SendPort port, message) {
-  var receivePort = new ReceivePort();
-  port.send({
-    'message': message,
-    'replyTo': receivePort.sendPort
-  });
-
-  return Chain.track(receivePort.first).then((response) {
-    if (response['type'] == 'success') return response['value'];
-    assert(response['type'] == 'error');
-    var exception = _deserializeException(response['error']);
-    return new Future.error(exception, exception.stackTrace);
-  });
-}
-
-/// An [AssetNotFoundException] that was originally raised in another isolate. 
-class _CrossIsolateAssetNotFoundException extends dart.CrossIsolateException
-    implements AssetNotFoundException {
-  final AssetId id;
-
-  String get message => "Could not find asset $id.";
-
-  /// Loads a [_CrossIsolateAssetNotFoundException] from a serialized
-  /// representation.
-  ///
-  /// [error] should be the result of
-  /// [_CrossIsolateAssetNotFoundException.serialize].
-  _CrossIsolateAssetNotFoundException.deserialize(Map error)
-      : id = new AssetId(error['package'], error['path']),
-        super.deserialize(error);
-
-  /// Serializes [error] to an object that can safely be passed across isolate
-  /// boundaries.
-  static Map serialize(AssetNotFoundException error, [StackTrace stack]) {
-    var map = dart.CrossIsolateException.serialize(error);
-    map['package'] = error.id.package;
-    map['path'] = error.id.path;
-    return map;
-  }
-}
-
-/// Serializes [error] to an object that can safely be passed across isolate
-/// boundaries.
-///
-/// This handles [AssetNotFoundException]s specially, ensuring that their
-/// metadata is preserved.
-Map _serializeException(error, [StackTrace stack]) {
-  if (error is AssetNotFoundException) {
-    return _CrossIsolateAssetNotFoundException.serialize(error, stack);
-  } else {
-    return dart.CrossIsolateException.serialize(error, stack);
-  }
-}
-
-/// Loads an exception from a serialized representation.
-///
-/// This handles [AssetNotFoundException]s specially, ensuring that their
-/// metadata is preserved.
-dart.CrossIsolateException _deserializeException(Map error) {
-  if (error['type'] == 'AssetNotFoundException') {
-    return new _CrossIsolateAssetNotFoundException.deserialize(error);
-  } else {
-    return new dart.CrossIsolateException.deserialize(error);
-  }
-}