Version 0.8.10.2

dart/sdk/lib/_internal/pub/lib/src/barback/dart2js_transformer.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 pub.dart2js_transformer;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:analyzer/analyzer.dart';
@@ skipping 16 matching lines @@
   final PackageGraph _graph;
 
   /// Whether the JavaScript output should be minified.
   final bool _minify;
 
   /// The [AssetId]s the transformer has discovered so far. Used by pub build
   /// to determine where to copy the JS bootstrap files.
   // TODO(rnystrom): Do something cleaner for this, or eliminate those files.
   final entrypoints = new Set<AssetId>();
 
+  /// If this is non-null, then the transformer is currently being applied, so
+  /// subsequent calls to [apply] will wait for this to finish before
+  /// proceeding.
+  ///
+  /// Dart2js uses lots of memory, so if we try to actually run compiles in
+  /// parallel, it takes down the VM. Instead, the transformer will force
+  /// all applies to be sequential. The tracking bug to do something better
+  /// is here: https://code.google.com/p/dart/issues/detail?id=14730.
+  Future _running;
+
   Dart2JSTransformer(this._graph, {bool minify})
       : _minify = minify == true ? true : false;
 
   /// Only ".dart" files within "web/" are processed.
   Future<bool> isPrimary(Asset asset) {
     return new Future.value(
         asset.id.extension == ".dart" &&
         asset.id.path.startsWith("web/"));
   }
 
   Future apply(Transform transform) {
+    // Wait for any ongoing apply to finish first.
+    // TODO(rnystrom): If there are multiple simultaneous compiles, this will
+    // resume and pause them repeatedly. It still serializes them correctly,
+    // but it might be cleaner to use a real queue.
+    // TODO(rnystrom): Add a test that this is functionality is helpful.
+    if (_running != null) {
+      return _running.then((_) => apply(transform));
+    }
+
+    var completer = new Completer();
+    _running = completer.future;
+
     var stopwatch = new Stopwatch();
     stopwatch.start();
 
     return transform.primaryInput.readAsString().then((code) {
       try {
         var id = transform.primaryInput.id;
         var name = id.path;
         if (id.package != _graph.entrypoint.root.name) {
           name += " in ${id.package}";
         }
@@ skipping 31 matching lines @@
 
         stopwatch.stop();
         transform.logger.info("Generated $id (${js.length} characters) in "
             "${stopwatch.elapsed}");
       }).catchError((error) {
         // The compile failed and errors have been reported through the
         // diagnostic handler, so just do nothing here.
         if (error is CompilerException) return;
         throw error;
       });
+    }).whenComplete(() {
+      completer.complete();
+      _running = null;
     });
   }
 }
 
 /// Defines methods implementig [CompilerInputProvider] and [DiagnosticHandler]
 /// for dart2js to use to load files from Barback and report errors.
 ///
 /// Note that most of the implementation of diagnostic handling here was
 /// copied from [FormattingDiagnosticHandler] in dart2js. The primary
 /// difference is that it uses barback's logging code and, more importantly, it
@@ skipping 133 matching lines @@
     var rootDir = _graph.entrypoint.root.dir;
     var sourcePath = path.fromUri(url);
     if (isBeneath(sourcePath, rootDir)) {
       var relative = path.relative(sourcePath, from: rootDir);
       return new AssetId(_graph.entrypoint.root.name, relative);
     }
 
     return null;
   }
 }