Add JsInitializerGenerator

lib/src/transformer/dart_initializer_generator.dart

@@ -0,0 +1,199 @@
+// Copyright (c) 2014, 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 js.transformer.dart_initializer_generator;
+
+import 'package:js/src/js_elements.dart';
+import 'package:logging/logging.dart';
+import 'package:quiver/iterables.dart';
+
+final _logger = new Logger('js.transformer.dart_initializer_generator');
+
+const JS_PREFIX = '__package_js_impl__';
+const JS_THIS_REF = '__js_this_ref__';
+
+class DartInitializerGenerator {
+  final String libraryName;
+  final String libraryPath;
+  final JsElements jsElements;
+
+  final buffer = new StringBuffer();
+
+  DartInitializerGenerator(this.libraryName, this.libraryPath, this.jsElements);
+
+  /**
+   * Returns the transformed source.
+   */
+  String generate() {
+    buffer.write(
+'''
+library ${libraryName}__init_js__;
+
+import 'dart:js' as js;
+import '${libraryPath}';
+import 'package:js/src/js_impl.dart' as $JS_PREFIX;
+
+final _obj = js.context['Object'];
+
+initializeJavaScriptLibrary() {
+''');
+
+    jsElements.proxies.forEach((Proxy proxy) {
+      if (proxy.constructor == null) return;
+      var name = proxy.name;
+      buffer.writeln("  $JS_PREFIX.registerFactoryForJsConstructor("
+          "$JS_PREFIX.context['${proxy.constructor}'], "
+          "($JS_PREFIX.JsObject o) => new $name.created(o));");
+    });
+
+    buffer.writeln("  var lib = $JS_PREFIX.context['dart'];");
+
+    jsElements.exportedLibraries.values.forEach(_generateLibraryExportCall);
+
+    buffer.writeln('}');
+
+    jsElements.exportedLibraries.values.forEach(_generateLibraryExportMethod);
+
+    return buffer.toString();
+  }
+
+  _generateLibraryExportCall(ExportedLibrary library) {
+    buffer.writeln("  _export_${library.getPath('_')}(lib);");
+  }
+
+  _generateLibraryExportMethod(ExportedLibrary library) {
+    buffer.writeln(
+'''
+
+void _export_${library.getPath('_')}($JS_PREFIX.JsObject parent) {
+  js.JsObject lib = parent['${library.name}'];
+''');
+
+    library.declarations.values.forEach(_generateDeclarationExportCall);
+    library.children.values.forEach(_generateLibraryExportCall);
+
+    buffer.writeln('}');
+
+    library.children.values.forEach(_generateLibraryExportMethod);
+    library.declarations.values.forEach(_generateDeclarationExport);
+  }
+
+  void _generateDeclarationExportCall(ExportedElement element) {
+    if (element is ExportedClass) {
+      buffer.writeln("  _export_${element.getPath('_')}(lib);");
+    }
+  }
+
+  void _generateDeclarationExport(ExportedElement element) {
+    if (element is ExportedClass) {
+      _generateClass(element);
+    }
+  }
+
+  void _generateClass(ExportedClass c) {
+    buffer.writeln(
+'''
+
+void _export_${c.getPath('_')}($JS_PREFIX.JsObject parent) {
+  var constructor = parent['${c.name}'];
+  $JS_PREFIX.registerJsConstructorForType(${c.name}, constructor['_wrapDartObject']);
+  var prototype = constructor['prototype'];
+''');
+
+    c.children.values.forEach(_generateClassMember);
+
+    buffer.writeln("}");
+  }
+
+  void _generateClassMember(ExportedElement e) {
+    if (e is ExportedConstructor) {
+      _generateConstructor(e);
+    } else if (e is ExportedMethod) {
+      _generateMethod(e);
+    } else if (e is ExportedField) {
+      _generateField(e);
+    }
+  }
+
+  void _generateConstructor(ExportedConstructor c) {
+    var constructorName = c.name == '' ? '_new' : '_new_${c.name}';
+    var dartParameters = _getDartParameters(c.parameters);
+    var jsParameters = _getJsParameters(c.parameters);
+    var namedPart = c.name == '' ? '' : '.${c.name}';
+    buffer.writeln("  constructor['$constructorName'] = ($jsParameters) => "
+        "new ${c.parent.name}$namedPart($dartParameters);");
+  }
+
+  void _generateMethod(ExportedMethod c) {
+    var dartParameters = _getDartParameters(c.parameters);
+    var jsParameters = _getJsParameters(c.parameters, withThis: true);
+    buffer.write(
+'''
+
+  // method ${c.name}
+  prototype['${c.name}'] = new js.JsFunction.withThis(($jsParameters) {
+    return  $JS_THIS_REF.${c.name}($dartParameters);
+  });
+''');
+  }
+
+  void _generateField(ExportedField f) {
+    var name = f.name;
+    var className = f.parent.name;
+    buffer.write(
+'''
+  // field $name
+  _obj.callMethod('defineProperty', [prototype, '$name',
+      new js.JsObject.jsify({
+        'get': new js.JsFunction.withThis((o) => (o[$JS_PREFIX.DART_OBJECT_PROPERTY] as $className).$name),
+        'set': new js.JsFunction.withThis((o, v) => (o[$JS_PREFIX.DART_OBJECT_PROPERTY] as $className).$name = v),
+      })]);
+''');
+  }
+
+
+  String _getJsParameters(List<ExportedParameter> parameters,
+      {bool withThis: false}) {
+    var requiredParameters = parameters
+        .where((p) => p.kind == ParameterKind.REQUIRED)
+        .map((p) => p.name);
+    var positionalParameters = parameters
+        .where((p) => p.kind == ParameterKind.POSITIONAL)
+        .map((p) => p.name);
+    var namedParameters = parameters
+        .where((p) => p.kind == ParameterKind.NAMED)
+        .map((p) => p.name);
+    var jsParameterList = withThis ? [JS_THIS_REF] : [];
+    jsParameterList.addAll(requiredParameters);
+    var jsParameters = jsParameterList.join(', ');
+    if (positionalParameters.isNotEmpty) {
+      jsParameters += ', [' + positionalParameters.join(', ') + ']';
+    } else if (namedParameters.isNotEmpty) {
+      jsParameters += ', [__js_named_parameters_map__]';
+    }
+    return jsParameters;
+  }
+
+  String _getDartParameters(List<ExportedParameter> parameters) {
+    var requiredParameters = parameters
+        .where((p) => p.kind == ParameterKind.REQUIRED)
+        .map((p) => p.name);
+    var positionalParameters = parameters
+        .where((p) => p.kind == ParameterKind.POSITIONAL)
+        .map((p) => p.name);
+    var namedParameters = parameters
+        .where((p) => p.kind == ParameterKind.NAMED)
+        .map((p) => p.name);
+    var dartNamedParameters = namedParameters.map((name) =>
+        "${name}: _getOptionalArg(__js_named_parameters_map__, '${name}')");
+    var dartParameters = concat([
+            requiredParameters,
+            positionalParameters,
+            dartNamedParameters])
+        .join(', ');
+
+    return dartParameters;
+  }
+
+}

lib/src/transformer/entry_point_transformer.dart

@@ -11,7 +11,6 @@ import 'package:barback/barback.dart' show Asset, AssetId, Transform,
 import 'package:code_transformers/resolver.dart' show Resolver,
     ResolverTransformer, Resolvers, isPossibleDartEntryId;
 import 'package:logging/logging.dart' show Logger;
-import 'package:path/path.dart' as path;
 
 import 'utils.dart';
 
@@ -46,51 +45,83 @@ class EntryPointTransformer extends Transformer with ResolverTransformer {
         .map((lib) {
           // look for initializer library
           var libAssetId = resolver.getSourceAssetId(lib);
-          var initializerAssetId = libAssetId.addExtension(INITIALIZER_SUFFIX);
-          return transform
-              .getInput(initializerAssetId)
-              .catchError((e) => null,
-                  test: (e) => e is AssetNotFoundException);
+          var dartInitializerAssetId =
+              libAssetId.addExtension(DART_INITIALIZER_SUFFIX);
+          var jsInitializerAssetId =
+              libAssetId.addExtension(JS_INITIALIZER_SUFFIX);
+          return [
+              transform
+                  .getInput(dartInitializerAssetId)
+                  .catchError((e) => null,
+                      test: (e) => e is AssetNotFoundException),
+              transform
+                  .getInput(jsInitializerAssetId)
+                  .catchError((e) => null,
+                      test: (e) => e is AssetNotFoundException),
+          ];
+        });
+
+    var dartInitializerFutures = initializerFutures.map((l) => l[0]);
+    var jsInitializerFutures = initializerFutures.map((l) => l[1]);
+
+    var dartImports = new StringBuffer('\n');
+    var dartInitializerCalls = new StringBuffer();
+
+    var dartFuture = Future.wait(dartInitializerFutures)
+        .then((initializerAssets) {
+          for (Asset asset in initializerAssets.where((a) => a != null)) {
+            var id = asset.id;
+            var importUri = getImportUri(id, input.id);
+            if (importUri == null) continue;
+            var prefix = assetIdToPrefix(id);
+            dartImports.writeln("import '$importUri' as $prefix;");
+            dartInitializerCalls
+                .writeln("  $prefix.initializeJavaScriptLibrary();");
+          }
         })
-        .where((f) => f != null);
-    return Future.wait(initializerFutures).then((initializerAssets) {
-      var imports = new StringBuffer('\n');
-      var calls = new StringBuffer();
-      for (Asset asset in initializerAssets.where((a) => a != null)) {
-        var id = asset.id;
-        var importUri = getImportUri(id, input.id);
-        if (importUri == null) continue;
-        var prefix = assetIdToPrefix(id);
-        imports.writeln("import '$importUri' as $prefix;");
-        calls.writeln("  $prefix.initializeJavaScriptLibrary();");
-      }
-
-      var initMethod = 'initializeJavaScript() {\n$calls}\n';
-      var insertImportOffset = getInsertImportOffset(library);
-      var initMethodOffset = library.source.contents.data.length;
-      transaction.edit(insertImportOffset, insertImportOffset, '$imports');
-      transaction.edit(initMethodOffset, initMethodOffset, initMethod);
-      var printer = transaction.commit();
-      printer.build(input.id.path);
-      transform.addOutput(new Asset.fromString(input.id, printer.text));
-    });
+        .then((_) {
+          var initMethod = 'initializeJavaScript() {\n$dartInitializerCalls}\n';
+          var insertImportOffset = getInsertImportOffset(library);
+          var initMethodOffset = library.source.contents.data.length;
+          transaction.edit(insertImportOffset, insertImportOffset,
+              '$dartImports');
+          transaction.edit(initMethodOffset, initMethodOffset, initMethod);
+          var printer = transaction.commit();
+          printer.build(input.id.path);
+          transform.addOutput(new Asset.fromString(input.id, printer.text));
+        });
+
+    var jsInitializerScript = new StringBuffer('''
+
+window.dart = window.dart || {};
+
+window.dart.Object = function DartObject() {
+  throw "not allowed";
+};
+
+window.dart.Object._wrapDartObject = function(dartObject) {
+  var o = Object.create(window.dart.Object.prototype);
+  o.__dart_object__ = dartObject;
+  return o;
+};
+
+''');
+
+    var jsFuture =
+        Future.wait(jsInitializerFutures)
+        .then((assets) => Future.wait(assets
+            .where((a) => a != null)
+            .map((Asset a) => a.readAsString())))
+        .then((initializerSources) {
+          for (String source in initializerSources) {
+            jsInitializerScript.writeln(source);
+          }
+        }).then((_) {
+          var jsInitializerId = input.id.addExtension('_initialize.js');
+          var asset = new Asset.fromString(jsInitializerId,
+              jsInitializerScript.toString());
+          transform.addOutput(asset);
+        });
+    return Future.wait([dartFuture, jsFuture]);
   }
 }
-
-final illegalIdRegex = new RegExp(r'[^a-zA-Z0-9_]');
-
-String assetIdToPrefix(AssetId id) =>
-    '_js__${id.package}__${id.path.replaceAll(illegalIdRegex, '_')}';
-
-// TODO(justinfagnani): put this in code_transformers ?
-String getImportUri(AssetId importId, AssetId from) {
-  if (importId.path.startsWith('lib/')) {
-    // we support package imports
-    return "package:${importId.package}/${importId.path.substring(4)}";
-  } else if (importId.package == from.package) {
-    // we can support relative imports
-    return path.relative(importId.path, from: path.dirname(from.path));
-  }
-  // cannot import
-  return null;
-}